摘要:

Abstract.The effect of total body irradiation on bone resorption is studied. Resorption is induced by applying an orthodontic device. A greater increase in bone resorption is observed in animals submitted to total body irradiation plus orthodontic force application, than in those submitted to orthodontic force alone. The increase in erosive areas began before an increase in the number of osteoclasts was noted. Irradiation resulted in an increased number of osteoclasts.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01668.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.The parotid gland and knee joint of immunized rats were challenged with the sensitizing antigen. Sialoadenitis developed in over half of these rats after one and three challenges via the parotid duct. On the other hand, most glands were normal after five, seven and eight intraductal challenges in spite of the presence of precipitating antibodies in the scrum and hemagglutinating antibodies in the parotid saliva; in only a few animals did chronic destructive adenitis ensue. This contrasted with the incidence and severity of synovitis, which increased with the number of intra‐articular injections of antigen. The non‐reactivity of the gland is antigen specific in as much as acute adenitis resulted from intraductal instillation of a second antigen following multiple challenges with another one in rats sensitized with two antigens. The results evince a difference in the local reactivity between the salivary gland and synovial membr

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01669.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.The ratio of functional parenchymal (acinar and duct) cells to intracapsular fat and connective tissue in human submandibular salivary glands is seen microscopically to differ from subject to subject. In the present analysis of an apparently age‐related change, a modification of the random‐point counting method of Chalkley (1943) of determining the relative volumes of tissue constituents from histological sections was applied to the submandibular glands of a randomly chosen sample of 36 subjects (six from each decade of age from 25–84 years) from a series of 211 consecutive autopsies. Reproducibility tests of the method of measurement and also observations on a further group of 19 healthy control subjects who had died “sudden” deaths, were made. When the values for the volume, of functional mass of acinar and duct cells relative lo that of fat and connective tissue were analyzed in relation to age, a gradual significant reduction through adult life was found (regression coefficient b =–0.28, p<0.01). Moreover, the values for a further group 5–14 years of age fell close to the extrapolated regression line of the groups aged from 25 to 84 years old. The trend for reduction may therefore begin in childhood. Analysis did not indicate that either fat or connective tissue alone predominated in the replacement of secretory cells. The values were not related to the adiposity of (he subject, and no trend for change with age was found in the fresh wet weights of 60 glands from subjects aged 25–74 years. The evidence indicates an average loss of a quarter of the relative secretory cell volume between childhood and old age, by which time the more extremely affected glands may hav

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01670.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.The effect of serum inhibitors on determinations of collagenolytic activity in culture fluids of healthy (G.I.=0) and mildly inflamed (G.I.=1) gingival tissue was studied. Gingival biopsies obtained at the beginning of the experimental gingivitis period (G.I.=0) and after approximately three weeks of no oral hygiene (G.I.=1) were subjected to tissue culture procedures previously utilized for the determination of collagenolytic activity. Inhibition of collagenase activity was evaluated by denaturing scrum inhibitors retained in culture fluid with sodium thiocyanate or by adding culture fluid from normal and inflamed tissues to a partially purified collagenase preparation.A decrease in collagenolytic activity was consistently demonstrable in untreated culture fluids of gingival tissue manifesting G.I.=1 as compared lo those exhibiting G.I.=0. When enzyme containing culture fluids were treated with NaSCN. however, no essential difference was detected. While culture fluids from healthy gingiva showed no inhibition of partially purified collagenase, culture fluids from tissues manifesting mild inflammation inhibited enzyme activity by approximately 60 %.A number of cell types associated with the periodontium have the ability to produce a specific collagenase. The results of this investigation suggest, however, thatin vitrodeterminations of collagenolytic activity in culture fluids of normal and inflamed tissues may be influenced by specific scrum inhibitors.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01671.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.A new method has been developed for the reproducible induction of rat salivary adenocarcinomas. Conventional means were used to induce fibrosarcoma and squamous cell carcinomas. The three tumors were compared for their ability to grow in tissue culture and syngeneic irradiated hosts. Based on the evidence of this system, squamous cell carcinoma appears to show the least biologic activity of the three tumors, a fact which may be tentatively explained by a predominance of keratinizing rather than replicating cells in this tumor.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01672.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.Ultrastructural studies have been carried out on epithelium taken from seven cases of non‐erosive oral lichen planus. Structural abnormalities observed have been consistent with light microscopic findings but no cellular changes specific to lichen planus have been noted. In particular the intranuclear structures seen have been similar to those described in a number of other epithelial disorders. Discontinuities of the basement membrane have been observed, without thickening or duplication of the lamina densa. No evidence of a viral etiology for the condition has been detecte

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01673.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.In the course of transplantation studies using tooth germs from isologous mice, it was shown that as the tooth germs developed to form teeth, cysts also formed in the epithelium of the enamel organs. It was found that, these cysts were producing keratin. Cysts developed in association with all the developing tooth germs, and by 120 days post‐transplantation many of the cysts had completely enveloped the crowns of the developing teeth. It has been clearly demonstrated that in addition to enamel production, tooth germ epithelium is capable of cystic change and keratin formation. As many histological similarities exist between the experimentally induced keratin producing cysts and human odontogenic keratocysts, it is suggested that the development of the experimentally induced cysts from enamel organs actively involved in amelogenesis may be of direct significance to the etiology of human odontogenic keratocyst

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01674.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract.Sterile polished slabs of bovine enamel, mounted in small acrylic cylinders, were held in the mouth for 2 hours. The acquired pellicles deposited on the enamel surfaces were examined insituon the slabs or after transfer to microscope slides. Indirect immunofluorescent stainingin situafforded positive identification of IgA and lysozyme in pellicles. The preferred technique required acid separation of the pellicle from the enamel, transfer to a microscope slide, and fixation in cold ethanol. Histochemically, this pellicle appeared to he predominantly basic. Results of indirect immunofluorescent tracing indicated that IgA and lysozyme were regular constituents of the pellicle, amylase and IgG were less consistently detected, and albumin and fibrinogen were rarely encountered.

ISSN:0904-2512    

DOI:10.1111/j.1600-0714.1973.tb01675.x

出版商:Blackwell Publishing Ltd    

年代:1973

数据来源: WILEY