The murine melanoma subline B16-F1 of low brain- and lung-colonizing potential has been used to obtain brain-colonizing variant sublines by sequential selection in vivo for their abilities to form brain meningeal tumors. After fourteen and fifteen selections in syngeneic C57BL/6 mice sublines B16-B14b and B16-B15b, respectively, were established in culture. These were then assayed in vivo by injection of single tumor cell suspensions into the tail vein (i.v.), left ventricle of the heart (i.c.) or left common carotid artery (i.a.), and the resulting tumors were examined histologically. Injection of subline B16-B14b or B16-B15b resulted in brain meningeal tumor formation in the dura mater and leptomeninges with invasion into underlying brain parenchyma and also some brain ventricular tumors at the sites of i.a. injection. Lung colonization ability remained in the brain-selected sublines, although it was remarkably reduced in i.a. tumor cell-injected animals. The brain meningeal tumors that formed were of three types: intravascular, nodular or infiltrative. Injection of tumor cells i.v. resulted mainly in the establishment of the intravascular type of brain meningeal tumors with eventual perivascular invasion, while injection i.a. or i.c. resulted mostly in nodular or infiltrative type brain meningeal tumors. The B16-B14b brain meningeal tumors formed were small (less than 1 mm in diameter) and usually nonpigmented, while B16-B15b tumors were generally large (up to 7 mm in diameter) and pigmented. Host reactions towards B16-B14b and B16-B15b tumors at meningeal sites differed. The former B16 subline was characterized by extensive fibrosis with some immunocytic cell infiltration in and around the meningeal tumors, while the latter subline did not elicit such host reactions. In contrast, tumors in brain parenchyma failed to evoke observable host reactions, and there was little evidence of immunocyte cell infiltration or glial cell alterations.

Animals↗

PubMedDate not supplied

Differential tumor growth of blood-borne B16 melanoma variants in cerebral dura mater is related to tumor-host cell reactions.

Intracarotid injection of B16-B14b or B16-B15b melanoma cells, previously established from B16-F1 melanoma by in vivo selection fourteen- or fifteen-times, respectively, for brain surface colonization, preferentially produced tumor nodules in mice at brain surface sites, most frequently in the dura mater, followed by the leptomeninges and cerebral cortex. There was a marked difference, however, in tumor growth at these sites using the two B16 sublines. Intracarotid injection of B16-B14b cells rarely produced visible tumors, whereas B16-B15b cells formed deeply pigmented tumors up to 7 mm in diameter in the brain menings of almost all mice examined. Histologic and electron microscopic investigation revealed that B16-B14b tumors evoked dramatic immunocyte cell infiltration and granulomatous reactions, while B16-B15b tumors were accompanied by much less tumor-host cell reactions. Splenectomy or laparotomy 1-2 weeks before or after intracarotid injection of B16-B14b cells dramatically enhanced tumor growth in the dura mater without extensive tumor-host cell reactions. The results suggest that the differential growth of B16-B14b and B16-B15b tumor cells in the cerebral dura mater is based, in part, on the abilities of these melanoma cells to elicit host cell reactions.

Animals↗

PubMedDate not supplied

Fibrolipoma of the parotid in a child.

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Adipose Tissue↗

PubMedDate not supplied

Measurement of estrogenic activity of chemicals for the development of new dental polymers.

The estrogenic activities of 13 Bisphenol-A (BPA)-related chemicals for development of new polymers by three in vitro bioassay have been examined in the presence and absence of a post-mitochondrial metabolizing system (S9 mix). BPA, Bisphenol-B (BPB), Bisphenol-F (BPF), Bisphenol-S (BPS), 4,4-ethylidenebisphenol (BP1), 4,4-dihydroxybenzophenone (BP2), 2,2-bis (4-hydroxyphenyl)-hexafluoropropane (BP3), 4,4-(1,4-phenylenediisopropylidene) bisphenol (BP4), 4,4-cyclohexylidenebisphenol (BP5), 4,4-dihydroxydiphenyl ether (BP6), 4-hydroxydiphenylmethane (BP7), 4-cumylphenol (BP8) and 4,4-dihydroxydiphenyl sulfide (BP9) were each diluted with dimethyl sulfoxide to final concentrations ranging from 10(-7) to 10(-3) M in both the yeast two-hybrid system and in a fluorescence polarization system. Dilutions of 10(-9) to 10(-4) M were assayed in the E-screen, respectively. Except for BPS and BP4, the chemicals tested showed estrogenic activity in the absence of cut S9 mix preparation and the activity was enhanced with S9 mix. BPS, which was initially negative, was active with S9 mix in the yeast two-hybrid system. BP2 was weakly estrogenic with or without S9 mix. Chemicals other than BP2 were positive in the competition binding assay. All chemicals tested showed estrogenic activity in the E-screen, the concentration level of which was 10(4) times lower than those of the other two assays.

Animal Testing Alternatives↗

PubMedDate not supplied

Percutaneous radiofrequency lesioning of sensory branches of the obturator and femoral nerves for the treatment of hip joint pain.

BACKGROUND AND OBJECTIVES: The sensory innervation of the hip joint includes the sensory articular branches of the obturator and femoral nerves. In this report, we retrospectively evaluated 14 cases in which hip joint pain was treated by percutaneous radiofrequency lesioning of sensory branches of obturator and/or femoral nerves. METHODS: Fourteen patients who had hip joint pain and underwent percutaneous radiofrequency lesioning of sensory branches of obturator and/or femoral nerves were studied. In all cases, intra-articular hip joint block or articular branch block of obturator nerve with local anesthesia was transiently effective. Radiofrequency lesioning was performed at 75 degrees C to 80 degrees C for 90 seconds using an RFG-3B generator and Sluijter-Mehta cannulae kit (Radionics, Burlington, MA) for the obturator nerve in 9 patients and for both the obturator and femoral nerves in 5 patients. To assess pain intensity, a visual analog scale (VAS) was used. RESULTS: The VAS scores before and after the radiofrequency lesioning were 6.8 +/- 0.9 and 2.7 +/- 1.3, respectively. Twelve patients (86%) reported at least 50% relief of pain for 1 to 11 months. There were no side effects or motor weakness observed. CONCLUSIONS: Percutaneous radiofrequency lesioning of sensory branches of the obturator and femoral nerves is an alternative treatment in patients with hip joint pain, especially in those where operation is not applicable.

Adult↗

PubMedDate not supplied

Thickened gastric walls showing diffuse low attenuation on CT.

Thickened gastric walls of diffusely low attenuation were observed on CT of three of eight patients with mucinous adenocarcinoma in a retrospective review of 141 cases of gastric carcinoma. On pathologic examination the low attenuation correlated with large amounts of mucin in the pathologic specimens. Mucinous adenocarcinoma with abundant mucin should be included in the differential diagnosis of thickened gastric walls of diffusely low attenuation.

Adenocarcinoma, Mucinous↗

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Significance of p27 as a predicting marker for medroxyprogesterone acetate therapy against endometrial endometrioid adenocarcinoma.

We reported that p27 induced by medroxyprogesterone acetate (MPA) may be involved in the progestin-induced growth suppression of human endometrial adenocarcinoma cells. This study aimed at investigating whether p27 expression could be a predicting marker to evaluate the effectiveness of MPA therapy. The clinical responses of 15 patients with endometrial carcinoma treated with MPA were examined. p27 expression was evaluated by immunohistochemical staining. Percentage of positive nuclear staining was expressed as a strongly positive (SP) labeling index (LI). Before MPA treatment, SP LIs in the effective and noneffective groups were 22.6 +/- 14.3% and 9.1 +/- 9.2%. At 1-6 weeks in the MPA treatment, SP LIs increased in both groups and were significantly higher than those before the therapy. At 7-12 weeks, SP LIs in both groups decreased to the level of pretherapy. At 13-18 weeks, SP LIs in the effective group were 14.9 +/- 5.7%, whereas in the noneffective group, 1.1 +/- 2.0%. The former was significantly higher than the latter. p27 expression could predict the effectiveness of MPA treatment for endometrial carcinoma at an early stage of the 4-month period in MPA therapy and could be a useful predicting marker for MPA.

Adult↗

PubMedDate not supplied

Clear cell adenocarcinoma of the endometrium is a biologically distinct entity from endometrioid adenocarcinoma.

Clear cell adenocarcinoma (CCA) of the endometrium has a poor prognosis, although the biologic features of this rare tumor are not clear. In this study, we analyzed the expression of biologic markers relating to carcinogenesis, tumor growth, and progression. Thirteen cases of CCA were compared with cases of endometrioid adenocarcinoma (EMA) of the endometrium. Immunohistochemical staining for p53; Ki-67; cyclins A, D1, and E; E-cadherin; progesterone receptor (PR)-A and PR-B; P-glycoprotein; MLH1; and MSH2 was performed. Labeling indices of p53, Ki-67, and cyclins A, D1, and E in CCA were 46.4 +/- 24.3%, 52.1 +/- 20.5%, 37.9 +/- 21.4%, 12.3 +/- 27.9%, and 8.2 +/- 22.9%, respectively. E-cadherin was expressed in only 1 case (7.7%) of CCA, as compared to 39 cases (61.0%) of EMA. No CCAs were positive for PR-A and PR-B. P-glycoprotein was detected in seven cases (53.8%). Loss of either MLH1 or MSH2 expression occurred in eight cases (61.5%). High-level expression of p53, cyclin A, and P-glycoprotein, and low-level or no expression of cyclin E, E-cadherin, PR-A, and PR-B was observed in CCA compared with EMA. The mechanism of cell-cycle regulation in endometrial CCA is different from that in EMA and may influence its malignant potential. Endometrial CCA is a distinct entity from EMA.

Adenocarcinoma, Clear Cell↗

PubMedDate not supplied

Non-polypoid colorectal neoplasias: a multicentric study.

A total of 781 non-polypoid colorectal neoplasias harvested at 4 main Hospitals in Tokyo, Japan (n = 420) and at 4 different time-intervals at the Karolinska Hospital, Stockholm, Sweden (n = 361) were reviewed. By applying strict histologic definitions, the lesions were classified into adenomas with low grade dysplasia (LGD), with high grade dysplasia (HGD), intramucosal carcinomas (IMC) or submucosal carcinomas (SMC). Of the non-polypoid neoplastic lesions reviewed in Sweden, 82.8% (n = 299) had LGD. In Japanese patients only 42.6% (n = 179) had LGD (p < or = 0.001). On the other hand, as many as 42.4% (n = 178) of the non-polypoid lesions in Japanese patients had HGD, but only 14.1% (n = 51) of those in Swedish patients (p < or = 0.001). Whereas 15.0% (n = 63) of the non-polypoid neoplasias seen in Japan were IMC or SMC, only 3.0% (n = 11) of those seen in Sweden were IMC or SMC (p < or = 0.001). The cause(s) for these differences remains unclear. In Japan, however, a marked increased incidence of colonic cancer has been recorded in later years. Whether the "catching up phenomenon" by the Japanese with western colonic cancer incidence includes increased histologic aggressiveness of non-polypoid neoplastic polyps--as found in this survey--remains to be elucidated.

Adenoma↗

PubMedDate not supplied

Equilibrium strengths of denture polymers subjected to long-term water immersion.

PURPOSE: This study characterized the effect of water immersion on the strength of denture polymers. MATERIALS AND METHODS: Four denture-base polymers and four denture-reline polymers were tested for flexural strength at proportional limits (FSpl) at 24 hours and at monthly intervals. The equilibrium strength of each polymer was estimated. RESULTS: The denture polymers took from 24 hours to 4 months to reach their equilibrium strength. The equilibrium strengths of the denture polymers were significantly different. CONCLUSION: Water immersion affected the strength of most denture polymers. Different denture polymers behaved differently in response to water immersion.

Analysis of Variance↗

PubMedDate not supplied

Clinicopathological significance of the expression of CD44v2 in colorectal cancer.

Expression of CD44 variant isoforms has been reported to be correlated with faster progression of neoplastic diseases, metastasis and reduced survival period. In this study, the correlation between the expression of CD44v2 (v2) or CD44v6 (v6) and clinicopathological features was examined in Dukes B and C colorectal cancer using immunohistochemistry. V6 expression was not correlated with any clinicopathological indices or prognosis in either Dukes B or C. On the other hand, v2 expression was correlated significantly with recurrence rate and poorer prognosis in Dukes B colorectal cancer although there was no correlation between v2 expression and prognosis in Dukes C patients. The results suggest that v2 is a candidate for a prognostic marker in Dukes B colorectal cancer. CD44v2 expression may be an indication for adopting adjuvant chemotherapy in patients without lymph node metastasis.

Colorectal Neoplasms↗

PubMedDate not supplied

Strength of relined denture base polymers subjected to long-term water immersion.

PURPOSE: This study was undertaken to characterize the long-term equilibrium flexural strength at proportional limit (FSp) of 4 denture reline polymers processed onto 4 denture base polymers. MATERIALS AND METHODS: A 3-point flexural test was applied on rectangular specimens of each denture base polymer-denture reline polymer. Each specimen was immersed in water for 4 months prior to and 4 months after reline. RESULTS: Significant differences existed among the relined specimens because of the denture base polymer variable, the denture reline polymer variable, and their interaction (P < 0.05). The descending order in FSp according to the denture base polymer, arranged in terms of statistical significance was: Acron approximately Acron MC > Triad > Palapress Vario, where approximately denotes no significant difference between Acron and Acron MC. The descending order in FSp according to the denture reline polymer, arranged in terms of statistical significance was: Triad > Rebaron > Rebaron LC > Tokuso Rebase. Significant difference existed among all of the denture reline polymers. CONCLUSION: The present study showed that the long-term equilibrium strengths of 4 denture reline polymers processed onto 4 denture base polymers were different. The strength of the relined specimen of a denture base is dependent on the strength of the denture base polymer and that of the reline polymer.

Acrylic Resins↗

PubMedDate not supplied

Interleukin-6 inhibits radiation induced apoptosis in pancreatic cancer cells.

We have examined the relationship between the expression and activation of the IL-6 receptor and the possible involvement of IL-6 in the resistance of radiation-induced apoptosis in pancreatic cancer cells. Levels of IL-6 in the incubation media measured with ELISA were 1900 pg/ml in CFPAC-1, 54 pg/ml in HPAC and less than 0.2 pg/ml in MIAPaCa-2 and AsPC-1. Western blot demonstrated gp80 protein (IL-6 receptor a subunit) in all pancreatic cancer cell lines except in AsPC-1. When immunoprecipitation was performed, the bands indicating phosphorylated gp130 (IL-6Rbeta) were observed in CFPAC-1 and HPAC, however, no band was found in MIAPaCa-2 or in AsPC-1 cells. RT-PCR and Western blot demonstrated that mRNA and protein expression for Bcl-2 and Bcl-XL was substantially increased by the IL-6 treatment in CEPAC-1 cells, but not in AsPC-1 cells. Neither exogenous IL-6 nor neutralizing anti-IL-6 mAb affected the proliferation of CFPAC-1 and AsPC-1 cells. However, the IL-6 treatment significantly attenuated the susceptibility to radiation in CFPAC-1 cells but not in AsPC-1 cells, and the neutralizing anti-IL-6 mAb significantly increased the radiosensitivity of CFPAC-1 cells. The results indicated that IL-6 might be produced in a paracrine and/or autocrine fashion in pancreatic cancer cells. In-6 inhibits radiation-induced apoptosis and enhances the survival of the cells through a functional receptor system, which is associated with the up-regulation of anti-apoptotic Bcl-2 family proteins, especially Bcl-XL.

Apoptosis↗

PubMedDate not supplied

[Histopathological findings of coronary artery lesions resected by directional coronary atherectomy].

Eleven directional coronary atherectomy procedures were performed in seven patients with angina pectoris and four patients with myocardial infarction, 10 men and 1 woman aged 41 to 69 years (mean 57 +/- 7 years). The onset of angina pectoris or myocardial infarction had occurred 2 months to 17 years previously. The preoperative mean diameter of stenosis was 80 +/- 8%, and the mean residual diameter of stenosis was 6 +/- 9% (p < 0.01). Seven left anterior descending arteries and four right coronary arteries were treated. Five of the 11 patients received partial-thickness resections of medial tissue and two of the five patients received full-thickness resections of the media with adventitial tissue. No lesions showed aneurysms or perforations during coronary arteriography after the procedure. The resected tissue was examined microscopically. Intimal tissues stained with Masson's trichrome were classified into four groups according to the characteristics fibrous tissue and the amount of proliferative cells: Type I was old dense fibrous tissue, type II was relatively old fibrous tissue containing many proliferative cells, type III was new loose fibrous tissue containing many proliferative cells, and type IV was atheromatous plaque. The intimal tissues were type I in 48.0%; type II in 35.5%; type III in 14.8%; and type IV in 1.7%. Resected lesions without prior treatment (primary lesions) from five patients with histories of 3 months or less were characterized by much type II and type III tissue; (type I tissue, 33.8%; type II tissue, 51.1%; type III tissue, 14.5%; type IV tissue, 0.6%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗