Biomedical subjects

Yuan Ji

Publications and source records attributed to Yuan Ji.

42 records · Page 3Linked to original sources

PubMed2003

Herpes simplex virus type 1 infection associated with atrial myxoma.

Some findings suggest an infectious factor in cardiac myxoma and certain histopathological features indicate herpes simplex virus type 1 (HSV-1) infection. We hypothesized that HSV-1 may be involved in the pathogenesis of cardiac myxoma. Paraffin-embedded tissue samples from 17 patients with atrial myxoma were investigated for HSV-1 antigen by immunohistochemistry and viral genomic DNA by nested polymerase chain reaction. The histogenesis and oncogenesis of atrial myxoma were assessed by the expression of calretinin, Ki67, and p53 protein, respectively. Autopsy myocardial samples, including endocardium from 12 patients who died by accident or other conditions, were used for comparison. HSV-1 antigen was detected in atrial myxoma from 12 of 17 patients: 8 of these 12 samples were positive also for HSV-1 DNA. No HSV-1 antigen or DNA was found in tissue from the comparison group. Antigens of HSV-2, varicella-zoster virus, Epstein-Barr virus, and cytomegalovirus were not found in atrial myxoma. Calretinin was found in myxoma cells of all 17 cases but Ki67 was present only in smooth muscle cells or infiltrating cells in some cases. p53 was not detectable in any myxoma. Most infiltrating cells were cytotoxic T lymphocytes. These data suggest that HSV-1 infection is associated with some cases of sporadic atrial myxoma and that these may result from a chronic inflammatory lesion of endocardium.

Adolescent↗

PubMed2002

Hepatic angiomyolipoma: various appearances on two-phase contrast scanning of spiral CT.

The purpose of this study was to describe and analyze the various appearances of hepatic angiomyolipoma (AML) on the two-phase contrast scans of spiral CT and find out the valuable signs suggesting the diagnosis. Spiral CT scanning of pre- and post-contrast arterial phase, portal venous phase were performed in 12 cases. We found that 11 of 12 lesions appeared as hypodense, the other one appeared as slightly hyperdense on pre-contrast CT scans. On the arterial phase, 11 lesions were markedly enhanced, with the central vasculature opacification in eight lesions; the only other lesion showed no marked enhancement, but with massive vessels seen within the lesion. On the portal venous phase, eight lesions remained in enhancement with the central vessels also seen in six lesions. Our results revealed that two-phase contrast scanning could demonstrate some characteristic features of AML, such as fat components within the lesions, hypervascular tumors, the absence of capsule. Especially the central vessels within the lesions suggested strongly the diagnosis of AML. As for atypical cases, the diagnosis remained difficult and should be differentiated from other hypervascular lesions by means of other imaging modalities or needle puncture biopsy.

Adult↗

PubMed2002

Upstream binding factor up-regulated in hepatocellular carcinoma is related to the survival and cisplatin-sensitivity of cancer cells.

Upstream binding factor (UBF) is an RNA polymerase I-specific transcription factor. By representational difference analysis, Northern blot, and cDNA array analysis, up-regulation of UBF was detected in 12 of 17 clinical hepatocellular carcinoma samples comparing to the paired normal liver tissues. Introduction of UBF in human lung fibroblast cells that do not express UBF resulted in an accelerated rate of cell growth; on the other hand, antisense oligodeoxynucleotides (ODNs) treatment of UBF-expressing hepatoma cell lines reduced the level of UBF protein, suppressed the colony formation capacity of these cells on soft agarose, and finally caused cell death. Annexin V binding analysis suggested that anti-UBF ODN-caused cell death might involve weak apoptosis, however, DNA laddering and cleavage of poly (ADP-ribose) polymerase were not observed in these ODN-treated cells. Expression profiling of the anti-UBF ODN-treated cells using a human cDNA array revealed that the expression of 30 genes was altered in response to the inhibition of UBF expression. Notably, UBF expression could increase the cell sensitivity to the chemotherapeutic reagent cis-diaminedichloroplatinum (II). We proposed that UBF is fundamental to the survival of cells expressing the gene, and is potential as a target for screening anti-cancer drugs and an indicator in selecting chemotherapeutic reagents.

Antineoplastic Agents↗

PubMed2002

P53 immunohistochemical scoring: an independent prognostic marker for patients after hepatocellular carcinoma resection.

AIM: To confirm if p53 mutation could be a routine predictive marker for the prognosis of hepatocellular carcinoma (HCC) patients. METHODS: Two hundreds and forty-four formalin-fixed paraffin-embedded tumor samples of the patients with HCC receiving liver resection were detected for nuclear accumulation of p53. The percent of P53 immunoreactive tumor cells was scored as 0 to 3+ in P53 positive region (<10% -, 10-30% +, 31-50% ++, >50% +++). Proliferating cell nuclear antigen (PCNA) and some clinicopathological characteristics, including patients' sex, preoperative serum AFP level, tumor size, capsule, vascular invasion (both visual and microscopic), and Edmondson grade were also evaluated. RESULTS: In univariate COX harzard regression model analysis, tumor size, capsule status, vascular invasion, and p53 expression were independent factors that were closely related to the overall survival (OS) rates of HCC patients. The survival rates of patients with 3+ for P53 expression were much lower than those with 2+ or + for P53 expression. Only vascular invasion (P<0.05) and capsule (P<0.01) were closely related to the disease-free survival (DFS) of HCC patients. In multivariate analysis, p53 overexpression (RI 0.5456, P<0.01) was the most significant factor associated with the OS rates of patients after HCC resection, while tumor size (RI 0.5209, P<0.01), vascular invasion (RI 0.5271, P<0.01) and capsule (RI-0.8691, P<0.01) were also related to the OS. However, only tumor capsular status was an independent predictive factor (P<0.05) for the DFS. No significant prognostic value was found in PCNA-LI, Edmondson's grade, patients' sex and preoperative serum AFP level. CONCLUSION: Accumulation of p53 expression, as well as tumor size, capsule and vascular invasion, could be valuable markers for predicting the prognosis of HCC patients after resection. The quantitative immunohistochemical scoring for P53 nuclear accumulation might be more valuable for predicting prognosis of patients after HCC resection than the common qualitative analysis.

Adolescent↗

PubMed2002

Role and limitation of FMPSPGR dynamic contrast scanning in the follow-up of patients with hepatocellular carcinoma treated by TACE.

AIM: To evaluate the role and limitation of fast multiplanar spoiled gradient-recalled (FMPSPGR) MR dynamic contrast scanning in the follow-up of patients with HCC treated by transarterial chemoembolization (TACE). METHODS: Twenty-two patients with 24 HCC lesions confirmed by biopsy or surgical resection underwent MR imaging in 4-9wks after TACE with a superconducting 1.5 T MR scanner, including SE T(1)WI, T(2)WI and FMPSPGR dynamic contrast scanning. The signal intensities of all lesions on SE T(1)WI,T(2)WI and the enhancement patterns on FMPSPGR dynamic contrast scanning were observed, and the comparison was made between MRI findings and pathological results in all the cases. RESULTS: Of the 24 lesions, the signal intensities were various on SE T(1)WI and T(2)WI. On T(1)WI, 13 lesions appeared as hyperintense, 4 lesions were isointense and the other 7 lesions were hypointensese. Histologically, hyperintense lesions showed on T(1)WI were viable tumor or hemorrhage; isointensities were coagulative necrosis or inflammatory infiltration; hypointensities were tumor, liquified necrosis, coagulative necrosis or inflammatory infiltration. On T(2)WI, 15 lesions appeared as hyperintense, 3 lesions were isointense and the other 6 lesions were hypointensese. Hyperintense lesions showed on T(2)WI were residuals of viable tumor, hemorrhage, liquefied necrosis or inflammatory infiltration; isointense lesions were residuals of viable tumor or inflammatory infiltration; hypointense lesions were coagulative necrosis. On FMPSPGR dynamic contrast scanning, 18 of the 24 lesions enhanced on early-phase dynamic scanning corresponding to residuals of viable tumor and the other 6 lesions had no enhancement at this phase because complete necrosis were seen in the histologic examination. On delayed-phase dynamic scanning, 6 lesions had permanent enhancement appeared as inhomogeneous hyperintensity and both residuals of viable tumor and inflammatory infiltration were found by histologic examination. 18 lesions were hypointense at this phase and 8 of them coexisted with peripheral ring-like enhancement of the lesions resulting from viable tumors or inflammatory infiltration. CONCLUSION: FMPSPGR MR dynamic contrast scanning can reflect the pathologic changes of HCC treated by TACE. Especially, early-phase dynamic scanning can evaluate accurately residuals of viable tumor and necrosis in HCC lesions. FMPSPGR dynamic contrast scanning is useful in the follow-up of patients with HCC treated by TACE combined with SE T(1)WI and T(2)WI, but it is difficult to differentiate peripheral viable tumors from inflammatory infiltration.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Charging compensation of alumina samples by using an oxygen microinjector in the environmental scanning electron microscope.

A gas microinjector system was set up in an environmental scanning electron microscope (ESEM) to create an oxygen atmosphere around the alumina samples for the charging compensation under a pressure between 2 x 10(-5) Pa approximately 2 x 10(-2) Pa. At low pressures, the skirt effect of the electron scattering can be degraded, which results in improvement of the imaging contrast and increase of the signal/noise ratio. The sample current (I(SC)) and the Duane-Hunt limit were measured to evaluate the charging effect.

Journal Article↗