Antiproliferative effect of topic hyaluronic acid gel. Study in gingival biopsies of patients with periodontal disease.

Hyaluronic acid (HA) is the most abundant glycosaminoglycan of high molecular weight in the extracellular matrix of soft periodontal tissues. Our group recently demonstrated an HA-induced reduction in lymphoplasmocyte inflammatory infiltrate in periodontal disease. The objective of this study was to determine the effect of an HA gel of high molecular weight on cell proliferation, inflammation, and different periodontal lesion parameters. A double-blind clinical trial was conducted on the effect of an HA gel on cell proliferation in gingival biopsies from 28 patients with periodontal disease. A split-mouth design was used, randomly applying the gel to one quadrant and a placebo to the contralateral one. A gingival biopsy was taken for histopathological and immunohistochemical study, in order to determine the expression of cell proliferation antigen Ki-67 and to evaluate the inflammatory infiltrate. HA gel treatment induced a significant reduction in the proliferation index of the gingival epithelium, with 276 (range 234-317) Ki-67-positive cells per mm2 in treated samples versus 514 (range 158-876) per mm2 in controls (Mann-Whitney U test, p<0.003). In 13 patients, the number of Ki-67-positive fibroblastic cells was reduced by the treatment, whereas in 6 patients no differences were found (global difference, p=0.12). In 10 patients, Ki-67-positive cells were decreased in chronic inflammatory infiltrate present in the lamina propria, whereas in 6 patients no differences were found (global difference, p=0.054). We conclude that high molecular-weight HA gel reduces cell proliferation in epithelial cells such as fibroblasts and lymphocytes, abates the inflammatory process, and improves the periodontal lesion in patients with chronic periodontitis.

Presence of cytomegalovirus genome and leucocyte subsets in renal transplant biopsies. Relationship with prognosis.

The influence of immunosuppressant therapy and of the presence of CMV genome on the distribution of lymphoid subpopulations of the inflammatory infiltrate in renal graft rejection was analyzed, as was the role of both factors in the evolution and survival of the graft. The study included 22 patients treated with Cyclosporin A (CsA) and 22 patients treated with Azathioprine (AZA). Inflammatory infiltrate was studied by immunostaining with a panel of monoclonal antibodies, and CMV DNA was detected by in situ hybridization on tissue sections. In patients treated with CsA, increased cellularity was found at both glomerular and interstitial levels, consisting mainly of macrophages and T-cells, which was consistent with the higher rate of glomerulointerstitial rejection found in this group. In contrast, the vascular type of rejection predominated in AZA treated patients. However, the presence of CMV DNA did not influence the phenotype of the inflammatory infiltrate, and was not associated with any specific lesion. Furthermore, the final outcome of the renal graft was independent of the detection of CMV. Therefore, this study provides no evidence of any active role of the CMV genome in renal graft rejection, and suggests that therapy should be adapted to the type of rejection as defined on morphologic and immunophenotypic grounds.

Squamous cell carcinoma arising on a congenital fissure of the lower lip.

In this study we document a case of squamous cell carcinoma in a young man arising on a fissure of the lower lip. The fissure, which existed since birth, could be considered congenital. We report here the clinical and pathological aspects; the pathogenesis is discussed.

An ultrastructural analysis of vascular leiomyoma of the bladder.

We report a case of vascular leiomyoma of the bladder in a 62-year-old man. To our knowledge, this is the first ultrastructural study published on vascular leiomyoma of the bladder. The tumoral cells reproduced the smooth muscle cells. The vascular structures corresponded to capillaries and arterioles. We consider that the vascular component is not tumoral and its origin is related to mast cells.

Human melanoma cell lines: an immunofluorescence and ultrastructural study.

Two human melanoma cell lines (OAL-1 and OAL-2) were obtained from primary tumors. Electron microscopy and indirect immunofluorescence for S-100 protein and human melanoma associated antigen p97a were used to characterize the cell lines. Ultrastructural correlation between primary tumor cells and cultured cells was investigated. The ultrastructural features of OAL-2 cells were similar to those of primary tumor cells. However, OAL-1 cells showed a fibroblast-like appearance, quite different from that of the primary tumor cells. This fibroblast-like appearance persisted after 50 subcultures of the OAL-2 cell line and suggests cellular dedifferentiation. No spontaneous redifferentiation of the cells to the original phenotype of the primary tumor cells was observed even after 50 subcultures.

Leiomyomas of the ovary.

Two cases of ovarian leiomyoma as casual findings in oophorectomy specimens are reported. Both were small (1.5 and 1.0 cm), one had leiomyoblastomatous and symplastic features, and the other was associated with an adjoining multilocular mucinous cystadenoma and atypical hyperplasia in the endometrium. Both coexisted with uterine leiomyomas, which they resemble morphologically. Distinction from thecoma-fibroma was made by the immunohistochemical demonstration of desmin and characteristic electronmicroscopic features of smooth muscle.

Atypical germ cells in prepubertal cryptorchid testes.

Four cases of prepubertal cryptorchid testes with atypical germ cells were studied. These cells were characteristically large, showing a wide, pale cytoplasm and a large nucleus with both fine and coarse granular chromatin. Ferritin was shown to be absent. It is possible that these cells are dysplastic in nature and that they could form the basis of a premalignant intratubular lesion. Thus periodic follow-up of these patients is recommended.

Epithelioid leiomyoma of the vulva.

An ultrastructural and light-microscopic study of the second published case of epithelioid leiomyoma of the vulva is reported. The tumor occurred in the right labium minus of a 26-year-old nonpregnant female. Optic microscopy revealed a clear cell neoplasm with a marked relationship to arterial vessels from which it may originate. The ultrastructure was analogous to that of similar cases reported in the uterus and stomach.

Fibrolamellar hepatocellular carcinoma. An immunohistochemical and ultrastructural study.

Two cases of fibrolamellar carcinoma of the liver are reported in young female patients of 12 and 21 years of age. Small amounts of perinuclear alpha-fetoprotein were found, unrelated to hyaline globules, as well as alpha 1-antitrypsin in a periglobular fashion in isolated cells. Ferritin was present in a large number of cells. Ultrastructurally, the well differentiated nature of the neoplasm was substantiated by previously unreported findings such as intercellular lumina analogous to bile canaliculi and peroxisome-like bodies containing a central crystalloid. Filamentous material resembling Mallory's type of hyaline was also found. We conclude that both immunohistochemical and ultrastructural features reflect a high degree of differentiation.