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Biomedical subjects

L S Hansen

Publications and source records attributed to L S Hansen.

At least 73 records · Page 4Linked to original sources
PubMed1981

A short term effect of homogeneous internal irradiation of the mouse lung with 170Tm2O3 particles.

The short term effects on the free macrophage population in the mouse lung, following inhalation of thulium-170 oxide, have been studied, with a view to using the system as a model with which to compare the short term effects of inhomogeneous alpha irradiation. The clearance and distribution of thulium-170 was followed up to 44 days post inhalation. The mice had an initial lung burden (+/- SE) of 6.7 +/- 0.5 microCi 170Tm/g of lung and the pattern of removal of this could be described by a single exponential of half time 31 +/- 4 days. This exposure resulted in a uniform dose of about 24 Gy to the lung. The macrophage population was studied by counting cells lavaged from the lungs at intervals over the period of the experiment. The lung burden of 170Tm2O3 was found to decrease the free macrophage numbers by about a factor of 2 in 14 days with some slight recovery at 6 weeks post inhalation. It was found that nearly 50% of the activity in the lung lobes was removed by the lavages and that this fraction remained constant throughout.

Aerosols↗
PubMed1981

"Hyaline cells" in pleomorphic adenoma of salivary gland origin.

Fifty-two cases of pleomorphic adenoma of minor salivary gland origin and seventy-two cases of pleomorphic adenoma of major salivary gland origin were examined for the presence of hyaline cells (plasmacytoid cells). Hyaline cells were found in 38 percent of the minor salivary gland cases and 21 percent of the major salivary gland cases. When stained with hematoxylin and eosin, the hyaline cells exhibited an eccentric nucleus and a striking homogenous, ground-glass, eosinophilic cytoplasm. At the ultrastructural level, the cytoplasm of the hyaline cells was closely packed with intermediate-sized filaments having no apparent orientation. It is suggested that the hyaline cells are modified myoepithelial cells.

Adenoma, Pleomorphic↗
PubMed1981

Changing concepts of the junctional nevus and melanoma: review of the literature and report of case.

Junctional nevus is the rarest type of oral nevus and only three well-documented cases have been reported. The present study adds a fourth case to the literature. Junctional nevus must be carefully differentiated from atypical melanocytic hyperplasia and malignant melanoma, which are clinically similar lesions. Because their malignant potential is uncertain, it is recommended that oral junctional nevi be completely excised. The classification of pigmented nevi of skin and mucous membrane and the concepts of their relationship to malignant melanomas have been changing. The authors recommend a classification for oral lesions based on the work of Sagebiel.

Child, Preschool↗
PubMed1981

Verruciform xanthoma of the oral mucosa. Report of five cases and review of the literature.

Verruciform xanthoma is an uncommon lesion confined mainly to the oral mucosa. Only two extraoral cases have been reported, and these involved the genitalia. Clinically, verruciform xanthoma is a raised lesion with a papillary or granular surface, usually located on the gingiva or alveolar mucosa. Microscopically, it is characterized by epithelial cell proliferation and by the accumulation of xanthoma cells in the upper lamina propria. Five new cases are reported and analyzed together with an additional 29 cases found in a review of the literature.

Adult↗
PubMed1980

Pigmented nevi of the oral mucosa: a clinicopathologic study of 32 new cases and review of 75 cases from the literature. Part II. Analysis of 107 cases.

Review and analysis of data of seventy-five cases from the literature, together with an additional thirty-two new cases, revealed that nevi of the oral mucosa are not rare and may be more common than previously thought. Nevi of the intramucosal type are the most common, followed by the common blue nevus. Compound nevi are uncommon, and junctional nevi are very rare. The data are analyzed as to the location, presence of clinical pigmentation, configuration, size, and duration of the nevi, as well as the patient's age, sex, and race. Oral nevi (especially those that are clinically nonpigmented) are often misdiagnosed, indicating that they are far more common than they would seem from the reported cases. The potential for oral nevi to undergo malignant transformation is unclear because of the paucity of cases and limited follow-up. Nevertheless, we recommend that all oral pigmented nevi be removed.

Adolescent↗
PubMed1980

Angiolymphoid hyperplasia with eosinophilia (Kimura's disease).

Angiolymphoid hyperplasia with eosinophilia (Kimura's disease) primarily affects the skin of the head and neck and the oral mucosa. While the clinical picture is nonspecific, the variable microscopic tissue pattern often is diagnostic. The etiology is unknown, and treatment is unpredictable. A case is presented in which Kumura's disease was not suspected clinically prior to the biopsy. The patient responded to topical fluocinonide, and there was no evidence of an immunologic defect.

Adolescent↗
PubMed1980

Amalgam pigmentation (amalgam tattoo) of the oral mucosa. A clinicopathologic study of 268 cases.

A series of 268 cases of amalgam tattoo is analyzed both clinically and histologically. The most common location was the gingiva and alveolar mucosa, followed by the buccal mucosa. Histologically, the amalgam was present in the tissues as discrete, fine, dark granules and as irregular solid fragments. The dark granules were arranged mainly along collagen bundles and around blood vessels. They were also associated with the walls of blood vessels, nerve sheaths, elastic fibers, basement membranes of mucosal epithelium, striated muscle fibers, and acini of minor salivary glands. Dark granules were also present intracellularly within macrophages, multinucleated giant cells, endothelial cells, and fibroblasts. Although in 45% of the cases there was no tissue reaction to the amalgam, in 17% there was a macrophagic reaction and in 38% there was a chronic inflammatory response, usually in the form of a foreign body granuloma, with multinucleated giant cells of the foreign body and Langhans types. Asteroid bodies were also found in some of the foreign body giant cells.

Adolescent↗
PubMed1980

Atypical calcifying epithelial odontogenic tumor of the maxilla.

A case of atypical calcifying epithelial odontogenic tumor is reported to show that many different lesions can cause periapical radiolucent areas and to contribute to the expanding histologic spectrum of the calcifying epithelial odontogenic tumor. Methods used in differential diagnosis of radiolucent lesions in the jaws include: comprehensive history, clinical and radiographic examination, tooth vitality tests, laboratory tests, aspiration, and biopsy. To prevent hemorrhage, precautions should be taken before biopsy or surgery to rule out a vascular lesion. Proper treatment of odontogenic tumors requires thorough removal of the tumor for initial therapy and close, long-term, follow-up observation to check for recurrence.

Adult↗
PubMed1980

Reactive lesions of the gingiva. A clinicopathological study of 741 cases.

A series of 741 consecutive cases of localized hyperplastic lesions of the gingiva were studied. The lesions were reclassified into four groups: pyogenic granuloma, peripheral giant cell granuloma, fibrous hyperplasia and peripheral fibroma with calcification. This study indicates that there are some differences between these groups in age and sex distribution as well as in location and size of the lesion. Fibrous hyperplasia was the most common type, followed in descending order by pyogenic granuloma, peripheral fibroma with calcification and peripheral giant cell granuloma. The peripheral giant cell granuloma showed no sex predilection while fibrous hyperplasia, pyogenic granuloma and peripheral fibroma with calcification were more common in females. Pyogenic granuloma and peripheral fibroma with calcification occur in younger patients more often than fibrous hyperplasia, and thus may represent a stage in the development of fibrous hyperplasia.

Adolescent↗
PubMed1980

Medical palatine cyst and maxillary antral osteoma: report of an unusal case.

A case is presented of a patient with the coincidental occurrence of two unusual lesions, median palatine cyst and osteoma of the maxillary antrum. There was no atypia of either lesion, but this combination led to the impression that the median palatine cyst had eroded into the maxillary antrum. Both lesions are usually asymptomatic and were incidental findings in this case. An occlusal radiograph is best for showing the palatal radiolucent area and is usually diagnostic. The preferred treatment for median palatine cyst is enucleation; a palatal splint is an excellent aid for reapproximation of the mucoperiosteal flap. The maxillary antrum was explored to obtain a biopsy specimen for a microscopic diagnosis of the radiopaque lesion; this proved to be an osteoma. The diagnosis of an osteoma is an indication for a radiographic survey to rule out Gardner syndrome, which has serious implications.

Humans↗
PubMed1979

Melanotic macule of the oral mucosa. A clinicopathologic study of 105 cases.

A series of 105 cases of melanotic macule of the oral mucosa is analyzed, both clinically and histologically. In most patients the melanotic macule was a solitary lesion, and the most common location was the vermilion border, followed by the gingiva. Histologically, the melanotic macule is characterized by increased pigmentation in either the basal-cell layer, the lamina propria (mainly within melanophages), or in both locations. It is suggested that the term melanotic macule be reserved for lesions in which there is a definite clinicopathologic correlation between a clinically pigmented macule and the aforementioned histologic features and that the term focal melanosis be used only as a histologic designation when these features appear in clinically nonpigmented pathologic conditions.

Adolescent↗
PubMed1979

Pigmented nevi of the oral mucosa: a clinicopathologic study of 32 new cases and review of 75 cases from the literature. Part I. A clinicopathologic study of 32 new cases.

Pigmented nevi are much less common in the oral cavity than they are in the skin. The present study adds thirty-two new cases to the literature. The most common type of nevus was found to be the intramucosal, followed in decreasing order by the common blue nevus, compound nevus, and junctional nevus. The clinical and histologic features of the nevi are analyzed and discussed.

Adolescent↗
PubMed1979

Lead poisoning. A comprehensive review and report of a case.

Lead, a ubiquitous heavy metal which has realized increased use, can cause poisoning by environmental contamination in either its organic or its inorganic form. Lead poisoning can be either acute or chronic, with the latter being the more common. The clinical signs and symptoms of lead poisoning are nonspecific, resulting in a difficult diagnostic problem, especially when it is not industrially related. On occasions, the dentist or oral surgeon may be the first to see an afflicted patient because of oral manifestations.

Adult↗