HPV infection has been implicated strongly in the pathogenesis of human squamous cell carcinoma(SCC). We analysed a series of 28 surgically removed, invasive squamous cell carcinoma of the esophagus by polymerase chain reaction to detect HPV DNA using consensus primers and 8 type-specific primers of HPV (6, 11, 16, 18, 31, 33, 35, 51). HPV 6, 31, 35 or 51 DNA were detected in 20 out of 28 cases (71.4%) of the esophageal SCCs. HPV 51 was the most frequently detected type, occuring in 13 out of 28 cases (46.4%). p53 immunohistochemical staining was also performed to demonstrate any relationship to HPV DNA positivity. It showed positivity in 16 out of 28(57.1%) esophageal SCCs, and HPV DNA and p53 positivity were concurrently detected in 11 out of 28 cases of SCCs. There was no significant inverse relation between HPV DNA positivity and p53 expression(p>0.05). Our results supported HPV involvement in esophageal squamous cell carcinoma, and suggested there may be another pathway not related to the p53-binding pathway in the carcinogenesis of esophageal SCCs by HPV.
Humans

In order to observe the effects of Nicotine and NNK on cultured human gingival fibroblast, several factors were examined including mutagenicity, the number of cells attached culture plate surface through MTT test, the abundance of collagen & collagenase in mRNA level and collagenolytic activity in extracellular matrix. The results were as follows; 1. Regardless of the co-existence of S9, Nicotine did not show the mutagenicity by itself and NNK by itself showd the same result; However, dose related mutagenicity was shown in NNK with S9. 2. The number of fibroblasts attached cultured plate surface was measured by MTT procedure. The number of cells in Non-smokers increased at all time periods as compared to those of smoker. 3. Non-smoker's fibroblast treated by NNK or Nicotine was dose-dependently decreased in the number of cells when compared to untreated control. In higher dose, Nicotine showed the cellular toxicity , but NNK did not. 4. No change in the abundance of mRNA for proalpha1 and proalpha2 was shown in Nicotine treated group but in gingival fibroblasts following treatment with NNK, the abundance of mRNA for proalpha1, but not proalpha2 collagen was decreased. 5. The abundance of mRNA for collagenase was decreased when NNK was treated but no change occurred in Nicotine treated group. 6. The effect of NNK and Nicotine in collagenolytic activity showed that ,collagenase activity exclusively react to type I collagen, was increased in both group, but gelatinase exclusively react to type IV collagen was not influenced at all. Collagenase activity of smoker's fibroblast was also increased as much as Nicotine and NNK group. The findings suggest that both of Nicotine and NNK lead gingival fibroblast to decrease in the abundance of collagen. And it seems to be that Nicotine and NNK have independent pathway toward the gingival fibroblast.
Humans

No Abstract Available.
Humans*

Verrucous carcinoma of the larynx is a distinct and uncommon variant of well-differentiated squamous cell-carcinoma. The authors hybridized in situ a case of laryngeal verrucous carcinoma with DNA prebes to humman papillomavirus (HPV) 6, 11, 16, 18, 31, 33 and 35. The DNAs from the verrucous carcinoma of larynx hybridized with mixed DNA probes HPV-16/18 and 31/33/35. In addition, there was an evidence of HPV infection based on hybridization with mixed DNA probe HPV-6/11 in the adjacent papilloma tissue. By in situ DNA hybridization techniques, we clearly demonstrated human papillomavirus (HPV-16/18, and 31/33/35) related sequences in this neoplasm. These findings suggest the role of HPV-6/11 in the development of laryngeal papilloma ad HPV-16/18 and 31/33/35 probably on the progression to verrucous carcinoma.
Humans

No abstract available.
Humans

No abstract available.
Humans

No abstract available.
Humans

Among objectives of periodontal therapy, the principal one is the morphological and functional reconstruction of lost periodontal supporting tissues. This includes de novo formation of connective tissue attachment and the regrowth of alveolar bone. The use of enamel matrix derivative(EMD) may be a suitable means of regeneration new periodontal attachment in the infrabony defects. Implant used to replace lost tooth but, implantitis occurred after installation. The purpose of this study was to investigate the effects of EMD on differentiation and growth of osteoblast in titanium disc. Twentyfive millimeter diameter and 1mm thick Ti disc which was coated 25, 50, 100, 200microgram/ml of EMD(Emdogain(R)) used as experimental group, 25, 50, 100, 200ng/ml of rhBMP-2 as positive control group, and no coat as negative control group. A human osteosarcoma cell line Saos-2 was cultured in Ti disc and cell proliferation and Alkaline phosphatase (ALP) activity were measured at 1 and 6 days. PCR was performed at 2 and 8 hours. Semi-quantitative RT-PCR for mRNA expressions of various osteoblastic differentiation markers - type I collagen, ALP, osteopontin, and bone sialoprotein - were performed at appropriate concentrations based upon the results of MTT and ALP assay. Cultured cell-disc complexes were prepared for scanning electron microscopy (SEM) at 2 hour. Data were analyzed using Mann-Whitney and repeated- measures 1-way analysis of variance(SPSS software version 10,SPSS, Chicago, IL). After culture, there was more osteoblast in EMD100microgram/ml than in EMD50, 200microgram/ml on day 6. There was significant difference in experimental and positive control group compared control group, as times go by(1 and 6 days). Alkaline phosphatase activity was different significantly in EMD100, 200microgram/ml and BMP100, 200ng/ml on day 6. The results of reverse transcriptase-polymerase chain reaction (RT-PCR) showed that expression of mRNA for ALPase, collagen type I, osteopontin, bone sialoprotein and BMP-2 was detected at 2 hour and 8 hour in EMD200microgram/ml subgroup and BMP100ng/ml subgroup. The results of this study suggest that application of enamel matrix derivative on osteoblast attached to titanium surface facilitate the expression of bone specific protein and the differentiation and growth of osteoblast.
Humans

No abstract available.
Humans

No abstract available.
Humans