Effects of low-intensity laser irradiation on hormonal responsiveness of patients with pulmonary tuberculosis

The method of proteinic catabolism degree estimation in potential renal transplant recipients was elaborated. It is based on the urea and creatinine level in blood determination and calculation of the metabolism index according to the formula. The substantiation of the patients treatment tactics and estimation of its efficacy was permitted by determination of predominational metabolism tendency.     

Effect of static compression on proteoglycan biosynthesis by chondrocytes transplanted to articular cartilage in vitro

Mutant mice that lack either protein zero (P0) or connexin 32 (Cx32) were generated previously to investigate the function of these myelin proteins in peripheral nerves and to assess the value of these mice as animal models for hereditary human peripheral neuropathies. Mice that are completely devoid of P0 expression (P0(+/0)) show a complex phenotype that is characterized by hypomyelination, compromised myelin compaction, and degeneration of myelin and axons early in life. In contrast, young mouse mutants that have retained one wild-type allele of the P0 gene (P0(+/0)) reveal morphologically normal myelin but start to develop signs of demyelination and remyelination at 4 months of age. A similar late-onset myelin deficiency was observed in Cx32-deficient mice (Cx32(0/0)). We have now generated mice deficient for Cx32 and P0. In animals that lack both proteins (Cx32(0/0)/P0(0/0), the phenotype is morphologically identical to mice that solely lack P0. Animals that lack Cx32 and carry one functional P0 allele (Cx32(0/0/P0(+/0)) revealed demyelination and remyelination as evidenced by thin myelin and Schwann cell onion bulb formation already at the age of 4 weeks, a time point when no pathology was observed in the single mutants. These morphological deficits were also more prominent in 4-month-old Cx32(0/0)/P0(+/0)animals compared to the single mutants. Our data support the view that Cx32 and P0 are crucial molecules for the maintenance of myelin. Furthermore, the function of Cx32 in the peripheral nervous system appears to be largely dispensable when myelin compaction is impaired.     

The effect of strenuous versus moderate exercise on the metabolism of proteoglycans in articular cartilage from different weight-bearing regions of the equine third carpal bone

In the present multi-center study, non-submerged ITI implants were prospectively followed to evaluate their long-term prognosis in fully and partially edentulous patients. In a total of 1003 patients, 2359 implants were consecutively inserted. Following a healing period of 3-6 months, the successfully integrated implants were restored with 393 removable and 758 fixed restorations. Subsequently, all consecutive implants were documented annually up to 8 years. At each examination, the clinical status of all implants was evaluated according to predefined criteria of success. Therefore, the data base allowed the evaluation of 8-year cumulative survival and success rates for 2359 implants. In addition, cumulative success rates were calculated for implant subgroups divided per implant type, implant length, and implant location. Furthermore, the actual 5-year survival and success rates could be determined for 488 implants. During the healing period, 13 implants did not successfully integrate, whereas 2346 implants fulfilled the predefined criteria of success. This corresponds with an early failure rate of 0.55%. During follow-up, 19 implants were classified as failures due to several reasons. In addition, 17 implants (approximately 0.8%) demonstrated at the last annual examination a suppurative periimplant infection. Including 127 drop out implants (= 5.4% drop out rate) into the calculation, the 8-year cumulative survival and success rates resulted in 96.7% and 93.3%, respectively. The analysis of implant subgroups showed slightly more favorable cumulative success rates for screw type implants (> 95%) compared to hollow-cylinder implants (91.3%), and clearly better success rates for mandibular implants (approximately 95%) when compared to maxillary implants (approximately 87%). The actual 5-year survival and success rates of 488 implants with 98.2% and 97.3%, respectively, were slightly better than the estimated 5-year cumulative survival and success rates of 2359 implants indicating that the applied life table analysis is a reliable statistical method to evaluate the long-term prognosis of dental implants. It can be concluded that non-submerged ITI implants maintain success rates well above 90% in different clinical centers for observation periods up to 8 years.     

Human articular cartilage: in vitro correlation of MRI and histologic findings

The aim of our study was to correlate MRI with histologic findings in normal and degenerative cartilage. Twenty-two human knees derived from patients undergoing amputation were examined with 1.0- and 1. 5-T MR imaging units. Firstly, we optimized two fat-suppressed 3D gradient-echo sequences. In this pilot study two knees were examined with fast imaging with steady precession (FISP) sequences and fast low-angle shot (FLASH, SPGR) sequence by varying the flip angles (40, 60, 90 degrees) and combining each flip angle with different echo time (7, 10 or 11, 20 ms). We chose the sequences with the best visual contrast between the cartilage layers and the best measured contrast-to-noise ratio between cartilage and bone marrow. Therefore, we used a 3D FLASH fat-saturated sequence (TR/TE/flip angle = 50/11 ms/40 degrees) and a 3D FISP fat-saturated sequence (TR/TE/flip angle = 40/10 ms/40 degrees) for cartilage imaging in 22 human knees. The images were obtained at various angles of the patellar cartilage in relation to the main magnetic field (0, 55, 90 degrees). The MR appearances were classified into five categories: normal, intracartilaginous signal changes, diffuse thinning (cartilage thickness < 3 mm), superficial erosions, and cartilage ulcers. After imaging, the knees were examined macroscopically and photographed. In addition, we performed histologic studies using light microscopy with several different stainings, polarization, and dark field microscopy as well as electron microscopy. The structural characteristics with the cartilage lesions were correlated with the MR findings. We identified a hyperintense superficial zone in the MR image which did not correlate to the histologically identifiable superficial zone. The second lamina was hypointense on MRI and correlated to the bulk of the radial zone. The third (or deep) cartilage lamina in the MR image seemed to represent the combination of the lowest portion of the radial zone and the calcified cartilage. The width of the hypointense second zone correlated weakly to the accumulation of proteoglycans in the radial zone. The trilaminar MRI appearance of the cartilage was only visible when the cartilage was thicker than 2 mm. In cartilage degeneration, we found either a diffuse thinning of all layers or circumscribed lesions ("cartilage ulcer") of these cartilage layers in the MR images. Early cartilage degeneration was indicated by a signal loss in the superficial zone, correlating to the histologically proven damage of proteoglycans in the transitional and radial zone along with destruction of the superficial zone. We found a strong effect of cartilage rotation in the main magnetic field, too. A rotation of the cartilage structures caused considerable variation in the signal intensity of the second lamina. Cartilage segments in a 55 degreesangle to the magnetic main field had a homogeneous appearance, not a trilaminar appearance. The signal behavior of hyaline articular cartilage does not reflect the laminar histologic structure. Osteoarthrosis and cartilage degeneration are visible on MR images as intracartilaginous signal changes, superficial erosions, diffuse cartilage thinning, and cartilage ulceration.     

Repair of large full-thickness articular cartilage defects with allograft articular chondrocytes embedded in a collagen gel

Full-thickness articular cartilage defects are a major clinical problem; however, presently there is no treatment available to regeneratively repair these lesions. The current therapeutic approach is to drill the base of the defect to expose the subchondral bone with its cells and growth factors. This usually results in a repair tissue of fibrocartilage that functions poorly in the loaded joint environment. The use of phenotypically appropriate chondrocytes embedded in a collagen gel delivery vehicle may provide a method that could be used to repair full-thickness articular cartilage defects with functionally satisfactory hyaline cartilage. Allograft articular chondrocytes embedded in a type I collagen gel were transplanted into large (6 x 3 x 3 mm), full-thickness articular cartilage defects in condylar and patellar weight-bearing surfaces to develop clinically applicable methods to repair articular cartilage defects. Chondrocytes were isolated from the articular cartilage of 4-week-old New Zealand rabbits and embedded in type I collagen gels. This composite was transplanted into a full-thickness defect on the medial femoral condyle and patellar groove of adolescent host rabbits. The repair cartilage was assessed histologically by a semiquantitative scoring system and biomechanically with a microindentation technique of specimens 4-48 weeks after chondrocyte transplantation. Defects in both locations were repaired with histologically apparent hyaline cartilage observed from as early as 4 weeks until 48 weeks after transplantation. The repair cartilage in the medial femoral condyle was more irregular than in the patellar groove, but in all other respects was similar. The grafted tissue did not remodel and differentiate into the morphological zones seen in normal articular cartilage. No tidemark or subchondral bony plate formed even 48 weeks after transplantation. Biomechanically, the repaired cartilage demonstrated indentation values similar to normal articular cartilage 12 weeks after transplantation and remained the same 48 weeks after transplantation. By contrast, the control (i.e., empty) defects healed with tissue that exhibited very poor metachromatic staining and exhibited very high indentation values. Incomplete bonding of the repair tissue to the normal cartilage was seen, and the surface was significantly irregular with major discontinuities. These observations provide the basis for considering the use of allograft articular chondrocytes to repair articular cartilage defects in the weight-bearing regions of the knee.     

Tenascin-C and the development of articular cartilage

In comparison to the vast literature on articular cartilage structure and function, relatively little is known about how articular cartilage forms during embryogenesis and is endowed with unique phenotypic properties, most notably the ability to persist and function throughout postnatal life. In this minireview, we summarize recent studies from our laboratory suggesting that the extracellular matrix protein tenascin-C is involved in the genesis and function of articular chondrocytes. These and other data have led us to propose that tenascin-C may be part of in vivo mechanisms whereby articular chondrocytes develop at the epiphysis of long bone models, remain functional throughout postnatal life, and avoid the endochondral ossification process undertaken by the bulk of chondrocytes located in the metaphysis and diaphysis of skeletal models.     

The fate of the articular cartilage in intracapsular fracture of the femoral neck (articular cartilage in femoral neck fracture)

The fate of the articular cartilage of the hip joint with intracapsular neck fracture was studied by histological, histochemical and autoradiographic techniques and by using a polarized microscope and a scanning electron microscope. Cartilage specimens from 93 femoral heads and 7 acetabula were obtained from fractured hips 2 days to 4 1/3 years postfracture and from control hips with various disorders. The cartilage degeneration appeared 2 weeks after fracture and advanced steadily with time. The matrix was covered, invaded and ultimately replaced by the fibrous tissue. Chondrocyte viability, though it was lost from the surface, was recognized in the deep matrix even in the oldest fracture examined. It is concluded that the humoral factor directly caused by the injury as well as the biomechanical impairment, i.e. a loss of physical stress, may play an essential role in the pathogenesis of the degeneration. The possibility of regeneration was discussed.     

Treatment of retinoblastoma with the transscleral diode laser

PURPOSE: To report a case of retinoblastoma successfully treated by contact transscleral photocoagulation with a diode laser. METHODS: In an 18-month-old girl, a small (6.6 x 4.3 x 3.2-mm) discrete retinoblastoma anterior to the superotemporal arcade in the right eye was treated with transscleral photocoagulation using a diode laser (810 nm) and a fiberoptic probe. RESULTS: The tumor regressed after photocoagulation, leaving a pigmented chorioretinal scar. There was no regrowth of the tumor 12 months after photocoagulation. CONCLUSION: Contact transscleral photocoagulation with a diode laser may be a viable new treatment for small retinoblastoma.     

Reaction of hypochlorous acid with bovine nasal cartilage comparison to pig articular cartilage

The action of sodium hypochlorite (NaOCl) on bovine nasal cartilage was studied by proton nuclear magnetic resonance (1H-NMR) spectroscopy in order to model degradation processes of cartilage caused by neutrophil-derived hypochlorous acid. Nasal cartilage was chosen as a mean of comparison because it differs from articular cartilage in its composition. It contains some more proteoglycans, i.e. polymeric carbohydrates and less collagen than articular cartilage. This is important for studying the influence of hypochlorous acid on cartilage components (collagen and polysaccharides). Cartilage samples were incubated at 37 degrees C with phosphate buffer in the presence or absence of NaOCl. Supernatants were collected and assayed by NMR-spectroscopy. In the presence of pure phosphate buffer, the supernatants of bovine nasal cartilage were less rich in low molecular mass metabolites (e.g. amino acids, lactate) than articular cartilage. However, intense signals for highly mobile N acetyl groups of cartilage polysaccharides were detectable in nasal cartilage. NaOCl caused an increase in signals for acetate and formiate. Signals for N-acetyl groups rose only during the first 25 minutes of incubation with NaOCl. Then, their concentration decreased markedly. These changes were related to an enhanced release of chondroitinsulfate from nasal cartilage.     

Effect of monensin on rumen metabolism in vitro

The effect of Monensin (Rumensin, Eli Lilly & Co.) in incubations with mixed rumen microorganisms metabolizing carbohydrate or protein substrates was investigated. Monensin partly inhibited methanogenesis and increased propionate production, although the effect was not always statistically significant. Incubations with substrates specific for methane bacteria suggest that inhibition of methanogenesis by Monensin was not due to a specific toxic action on the methanogenic flora, but rather to an inhibition of hydrogen production from formate. Total and net microbial growth were considerably decreased by addition of Monensin, although the amount of substrate fermented was not altered, resulting in lowered values of microbial growth efficiency. In incubations with casein, Monensin lowered protein degradation in line with a lowered ammonia production, whereas a slight accumulation of alpha-amino nitrogen was observed. The results suggest that besides an influence of Monensin on the rumen carbohydrate fermentation pattern, another reason for the beneficial effects observed in vivo might be decreased food protein degradation in the rumen, altering the final site of protein digestion in the animal. Also, the possibility of a decrease in rumen microbial growth efficiency has to be considered when using Monensin as a food additive.     

Effect of cytochalasin D on articular cartilage cell phenotype and shape in long-term organ culture

It has been documented, on the basis of cell culture experiments, that cytochalasin treatment promotes a round cell shape in chondroblast cultures by altering the cytoskeleton, and that it simultaneously alters the balance between production of type I and type II collagens. The aim in this study was to monitor the deposition of pro-type-I and type II collagens, and possible changes in articular cartilage layers in the mandibular condyle of the mouse under the influence of Cytochalasin D (CD) when total craniomandibular joints of 5-day-old mice were cultured in one block. The experimental group comprised 20 Balb/c mice of both sexes. Twenty in vitro controls were cultured without the administration of cytochalasin. The mice in the third group were used as in vivo controls. The cells in the prechondroblast layer responded with a rapid change in shape when treated with CD and assumed a rounded morphology. The total thickness of the cell layer was reduced at 7 days. Immunostaining against pro-type-I collagen was intense in the narrow fibrous and prechondroblast layers in the CD-treated group, whereas the stained area was wider and the staining gradually reduced in the deeper cartilage layers in the in vitro controls. Staining against type II collagen became weaker at the end of the culturing period of the CD-treated group, whereas in the in vitro controls the staining against type II collagen was clearly visible at all observation times. These phenomena can be explained by changes in differentiation and the altered cell cycle of the chondroblasts in organ culture under the influence of CD.     

A novel cartilage protein (CILP) present in the mid-zone of human articular cartilage increases with age

A novel, somewhat basic noncollagenous protein was purified from guanidine hydrochloride extracts of human articular cartilage using cesium chloride density gradient centrifugation, followed by ion-exchange chromatography at pH 5, and gel filtration on two serially coupled columns of Superose 6 and Superdex 200. The protein of 91.5 kDa contains a single polypeptide chain substituted with N-linked oligosaccharides. It appeared unique to cartilage as studied by enzyme-linked immunosorbent assay and immunoblots of various tissue extracts. Its concentration in articular cartilages showed some variability with age being lower in young individuals. It represents a chondrocyte product, since it is synthesized by articular chondrocytes in explant cultures. Interestingly, the distribution of the protein in the articular cartilage provides important information on the nature of chondrocytes at different compartments in the tissue. Thus, chondrocytes in the middle/deeper layers of the tissue in particular, appeared to have produced the protein and deposited it in the interterritorial matrix. The protein was neither seen in the superficial nor in the deepest regions of the articular cartilage. Based on its immunolocalization we have named this protein CILP (cartilage intermediate layer protein).     

Effect of low-power laser irradiation on impulse conduction in anesthetized rabbits

Low-power laser analgesic effect was generally accepted in clinical cases, whereas there was no direct evidence to indicate that low-power laser irradiation suppressed an impulse conduction within a peripheral nerve. The effect of low-power laser irradiation on electrically evoked responses within the sural nerve was electrophysiologically analyzed in anesthetized rabbits. High threshold evoked responses (conduction velocity was about 11 m/sec, unmyelinated A delta), which were induced by an electrical stimulation to the peripheral stump of the nerve, were significantly suppressed (9 to 19% inhibition) during low-power laser irradiation, which applied to the exposed sural nerve between the stimulus site and the recording site. The suppressive effect was reversible and recovered to the control level after the irradiation. Experimental evidence indicated that low-power laser irradiation suppressed the impulse conduction of unmyelinated A delta afferents in peripheral sensory nerve, which caused a pain sensation. Our data suggest that low-power laser acts as a reversible direct suppressor of neuronal activity.     

Treatment of articular cartilage defects of the knee with autologous chondrocyte implantation

alpha 1-Adrenergic receptor-mediated responses are overwhelming in adult rat hepatocytes. Inversely, beta-responses are predominant over alpha 1-responses in the hepatocytes that have been cultured at a low cell density (10(4) cells/cm2) for 24 h. The insulin-EGF-induced DNA synthesis in the beta-response-dominant hepatocytes was doubled by beta-agonists or cAMP-generating agents added far behind (16-20 h) the addition of insulin/EGF; i.e., immediately before the entry into the S-phase of the cell cycle. Agonists of alpha 1-adrenergic or other Ca2+, mobilising receptors added to the alpha 1-response-dominant hepatocytes increased DNA synthesis only if they were added within 1-2 h after the addition of insulin/EGF, at the early stage of G1-phase. Agonists of "non-dominant" receptors were rather antagonistic to agonists of "dominant" receptors. Thus, agonists of alpha 1-adrenergic (and other Ca2+ mobilising) receptors and agonists of beta-adrenergic (and other cAMP-generating) receptors acted as comitogens in their own particular manners in the presence of growth factors in hepatocytes in which the respective receptor functions were dominant.     

Transscleral cyclophotocoagulation with the diode laser for neovascular glaucoma

Despite a high prevalence of canine dirofilariasis, there is no case of pulmonary dirofilariasis reported from Thailand. We herein report a case of multisystem Langerhans cell histiocytosis who had an incidental pulmonary dirofilariasis found at the time of autopsy as a solitary nodule at the periphery of the right lower lobe. This is the first reported case in Thailand. Association between pulmonary dirofilariasis and Langerhans cell histiocytosis has not been described before in the literature.     

Low-energy laser irradiation affects satellite cell proliferation and differentiation in vitro

Low-energy laser (He-Ne) irradiation was found to promote skeletal muscle regeneration in vivo. In this study, its effect on the proliferation and differentiation of satellite cells in vitro was evaluated. Primary rat satellite cells were irradiated for various time periods immediately after preparation, and thymidine incorporation was determined after 2 days in culture. Laser irradiation affected thymidine incorporation in a bell-shaped manner, with a peak at 3 s of irradiation. Three seconds of irradiation caused an induction of cell-cycle regulatory proteins: cyclin D1, cyclin E and cyclin A in an established line of mouse satellite cells, pmi28, and proliferating cell nuclear antigen (PCNA) in primary rat satellite cells. The induction of cyclins by laser irradiation was compatible with their induction by serum refeeding of the cells. Laser irradiation effect on cell proliferation was dependent on the rat's age. At 3 weeks of age, thymidine incorporation in the irradiated cells was more than twofold higher than that in the controls, while at 6 weeks of age this difference had almost disappeared. Myosin heavy chain (MHC) protein levels were twofold lower in the irradiated than in the control cells, whereas the proliferation of the irradiated cells was twofold higher. Fusion percentage was lower in the irradiated compared to non-irradiated cells. In light of these data, the promoting effect of laser irradiation on skeletal muscle regeneration in vivo may be due to its effect on the activation of early cell-cycle regulatory genes in satellite cells, leading to increased proliferation and to a delay in cell differentiation.