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61.
S Agarwal CS Chandra NP Piesco HH Langkamp L Bowen C Baran 《Canadian Metallurgical Quarterly》1998,66(3):932-937
Periodontal ligament (PDL) cells maintain the attachment of the tooth to alveolar bone. These cells reside at a site in which they are challenged frequently by bacterial products and proinflammatory cytokines, such as interleukin-1beta (IL-1beta), during infections. In our initial studies we observed that IL-1beta down-regulates the osteoblast-like characteristics of PDL cells in vitro. Therefore, we examined the functional significance of the loss of the PDL cell's osteoblast-like characteristics during inflammation. In this report we show that, during inflammation, IL-1beta can modulate the phenotypic characteristics of PDL cells to a more functionally significant lipopolysaccharide (LPS)-responsive phenotype. In a healthy periodontium PDL cells exhibit an osteoblast-like phenotype and are unresponsive to gram-negative bacterial LPS. Treatment of PDL cells with IL-1beta inhibits the expression of their osteoblast-like characteristics, as assessed by the failure to express transforming growth factor beta1 (TGF-beta1) and proteins associated with mineralization, such as alkaline phosphatase and osteocalcin. As a consequence of this IL-1beta-induced phenotypic change, PDL cells become responsive to LPS and synthesize proinflammatory cytokines. The IL-1beta-induced phenotypic changes in PDL cells were transient, as removal of IL-1beta from PDL cell cultures resulted in reacquisition of their osteoblast-like characteristics and lack of LPS responsiveness. The IL-1beta-induced phenotypic changes occurred at concentrations that are frequently observed in tissue exudates during periodontal inflammation (0.05 to 5 ng/ml). The results suggest that, during inflammation in vivo, IL-1beta may modulate PDL cell functions, allowing PDL cells to participate directly in the disease process by assuming LPS responsiveness at the expense of their normal structural properties and functions. 相似文献
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63.
SH Wray DG Cogan T Kuwabara HH Schaumburg JM Powers 《Canadian Metallurgical Quarterly》1976,82(3):480-485
Adrenoleukodystrophy is an X-chromosome-linked recessive disease characterized by primary atrophy of the adrenal glands with or without Addison's disease and low plasma cortisol levels, and a degeneration of white matter of the central nervous system with blindness. In suspected cases of adrenoleukodystrophy an impaired rise in plasma cortisol levels after adrenocorticotrophin stimulation may be diagnostic. With the electron microscope, pathognomonic intracytoplasmic lamellar inclusions have been seen in adrenal cortical cells, peripheral nerve Schwann's cells, testicular interstitial cells, and in macrophages of the brain. Adrenoleukodystrophy appears to be a genetically determined lipid storage disease with an error in membrane sterol metabolism. A 10-year-old boy with adrenoleukodystrophy had visual loss, a prominent early symptom. The ocular abnormality consisted of a disproportionate loss of nerve fibers from the macular region. No intracytoplasmic lamellar inclusions were identified in cells representing macrophages within the optic nerve. They contained myelin debris suggestive of end-stage disease. 相似文献
64.
A case of exogeneous hair damage caused by bleaching and cold waving is reported. The clinical picture showed brittle, lustreless, fallow hair. The light microscope showed irregular spreading of the cuticular cells. The scanning electron microscope revealed loss of the regular cuticular pattern, breakage of the edges of the cuticular cells, and wave-like separations of the cuticular cells from the cortex. The hair shafts showed multiple longitudinal indentations like seen on a tree trunk. 相似文献
65.
R Schwaab J Oldenburg EG Tuddenham HH Brackmann K Olek 《Canadian Metallurgical Quarterly》1993,83(3):450-458
In the present study DNA from 281 unrelated haemophilia A patients including 15 inhibitor patients has been analysed by Southern blotting technique. Using various restriction enzymes, cloned factor VIII cDNA probes and genomic fragments we have identified 14 mutations. Six of the mutations are novel partial factor VIII gene deletions. One deletion affects exon 1, two deletions concern exon 6, another deletion, of which breakpoints are sequenced, takes part of exon 16 and two deletions affect exon 26. Besides the deletions, eight point mutations have been found at the TaqI restriction sites of exons 18, 24 and 26. Five C-->T mutations resulted in nonsense mutations, one in exon 18, one in exon 26 and three in exon 24. Two G-->A mutations caused a missense mutation in exon 24 leading to an arginine/glutamine exchange. Although two patients showed this mutation, their clinical phenotypes were different, possibly due to an additional unidentified sequence polymorphism. A G-->T mutation in exon 26 substituted the arginine with leucine. All deletions and seven of the point mutations are associated with severe disease with a detectable inhibitor in the patient with the TaqI-point mutation in exon 18. One of the G-->A mutations is associated with mild haemophilia but the patient also has developed an inhibitor. Amongst these mutations the origin of the mutation could be determined in four kindred, one of which showed maternal mosaicism. 相似文献
66.
Structural studies were carried out on a monotypic immunoglobulin (Ig) isolated from a patient suffering from a colon tumor. Results indicated that the light (L) chain of this protein belonged to the VkappaII subgroup and was devoid of known Inv allotypic determinants, whereas the heavy (H) chain variable (V) region belonged to the VHIII subgroup and its constant (C) region was of the gamma1 subclass and was Gm (a+Z+). The amino acid sequence of a total of 106 residues has been determined for this molecule. An extra cysteine was present at the fourth hypervarible region of the heavy chain. Preliminary results indicated that the Fc fragment of this protein did not include the inter-heavy-chain disulfide bonds. 相似文献
67.
We have used the fluorescence in situ hybridization (FISH) technique to refine the localization of the cystic fibrosis transmembrane conductance regulator (CFTR) gene on human chromosome 7. The result shows that the gene is most likely located within band q31.3. 相似文献
68.
Pseudomonas aeruginosa can cause infections in AIDS patients who frequently do not have the usual predisposing conditions such as neutropenia and intravenous drug use. The infections due to P. aeruginosa may be difficult to treat in AIDS patients. Sinusitis has been increasingly recognized as a complication in patients with AIDS. This article describes a case of recurrent P. aeruginosa sinusitis which, until recently, was rarely reported in AIDS. 相似文献
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