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X Bu

Publications and source records attributed to X Bu.

At least 19 recordsLinked to original sources
PubMed2006

Significance of C4d deposition in the diagnosis of rejection after liver transplantation.

C4d immunohistochemical staining of liver allograft biopsies was performed to assess its relationship to other pathological changes in the liver. C4d deposition was detected in 69.2% of liver graft biopsies from patients under going rejection, 33.3% of liver graft biopsies from patients with hepatitis B relapse after transplantation, and 28.6% of liver biopsies from patients with hepatitis B. When rejection occurred C4d deposition was located in the vascular walls of portal areas and hepatic sinusoidal walls. Examination of biopsies from patients with hepatitis B relapse after transplantation or hepatitis B infection showed C4d deposition only in the vascular walls of the portal area. C4d deposition in both vascular walls of portal area and hepatic sinusoidal walls was detected in only one of 12 ischemia-reperfusion damage cases. Repeated biopsy of the same patient 1 month later revealed acute cellular rejection. No C4d deposition was found in biopsies from a patient with bile duct occlusion after liver transplantation. C4d might serve as a sensitive marker for the diagnosis of liver rejection.

Acute Disease↗
PubMed2005

Ki67 expression in different epithelial types in columnar lined oesophagus indicates varying levels of expanded and aberrant proliferative patterns.

AIMS: To evaluate proliferative patterns in metaplastic columnar epithelia of the oesophagus, classified as oxynto-cardiac (n = 43), cardiac (n = 45) intestinal without dysplasia (n = 41), dysplastic intestinal epithelium (n = 25), and adenocarcinoma (n = 15) by Ki67 immunohistochemistry. METHODS AND RESULTS: Abnormal patterns of Ki67 immunoreactivity were classified into (i) expanded proliferation, characterized by increased levels of Ki67 expression in the deep and mid third of the foveolar pit; and (ii) aberrant proliferation, characterized by positive staining in the surface epithelium and superficial third of the foveolar pit. A significant step-wise increase in the frequency of expanded proliferation was seen in oxynto-cardiac, cardiac, intestinal and dysplastic intestinal epithelium indicative of increasing levels of damage. Aberrant proliferation was absent in oxynto-cardiac mucosa, present at a low and similar level in cardiac, intestinal and low-grade dysplastic epithelia and at a significantly increased frequency in high-grade dysplasia. CONCLUSIONS: These findings suggest that oxynto-cardiac mucosa occurs in a low damage environment and intestinal metaplasia in a high damage environment along the length of the columnar lined oesophageal segment. Aberrant proliferative patterns with Ki67 staining are not useful in differentiating reactive epithelia from low-grade dysplasia, but may prove useful in the diagnosis of high-grade dysplasia.

Adenocarcinoma↗
PubMed2003

Herpes simplex virus type-1 infection upregulates cellular promoters and telomerase activity in both tumor and nontumor human cells.

Targeted gene expression through viral vectors has been a promising approach for gene therapy. However, the effects of viral gene products expressed from virus vectors on the expression of the host gene are not well known. In the present study, we examined the activities of cellular promoters, including the promoter for genes of human telomerase reverse transcriptase (hTERT), tyrosinase and probasin, in both tumor and normal cells after infection with herpes simplex virus type 1 (HSV-1) vectors. Our results showed that infection with replication-defective HSV-1 vectors significantly upregulated the activity of all three cellular promoters in a nonsequence specific fashion in all cell types tested. Furthermore, viral infection upregulated activities of the hTERT promoter and endogenous telomerase in nontumoral cells. Additional experiments suggested that the viral immediate-early gene product, infected cell protein 0, might be responsible for the deregulation of cellular promoter activity and activation of telomerase. Our study alerts to the potential risk of oncogenesis through deregulation of host gene expression, such as the telomerase by viral vectors in normal cells.

Androgen-Binding Protein↗
PubMed2002

Reduced risk of synovial sarcoma in females: X-chromosome inactivation?

Synovial sarcoma shows a characteristic t(X;18) translocation but not the expected female predominance in incidence. We speculate that, among females, one X-chromosome is inactivated and that only the translocation to an active X-chromosome leads to development of synovial sarcoma. Population-based cancer registry data from the SEER program support this hypothesis.

Adolescent↗
PubMed2001

Synthesis and cytotoxic activity of 7-oxo-7H-dibenz[f,ij]isoquinoline and 7-oxo-7H-benzo[e]perimidine derivatives.

A series of 7-oxo-7H-dibenz[f,ij]isoquinoline and 7-oxo-7H-benzo[e]perimidines bearing cationic side chains were prepared from aminoanthraquinones. The perimidines were prepared from 1-aminoanthraquinone by initial condensation with urea or dimethylacetamide. A series of 2-, 4-, 8-, and 11-carboxy derivatives of the dibenzisoquinolines were prepared from aminoanthraquinonecarboxylic acids. The cationic derivatives were prepared from these via amide, amine, or methylene linkers to study the effects of side chain positioning on biological activity. Within the series of carboxamide-linked compounds, the order of increasing cytotoxicity was 8- < 4- < 2- < 11-. The 2- and 4-carboxamides showed substantial growth delays against in vivo subcutaneous colon 38 tumors in mice, but the 11-carboxamide had curative activity in this refractory model and is being investigated further.

Animals↗
PubMed2001

Oxidative impairment in scrapie-infected mice is associated with brain metals perturbations and altered antioxidant activities.

Prion diseases are characterized by the conversion of the normal cellular prion protein (PrP(C)) into a pathogenic isoform (PrP(Sc)). PrP(C) binds copper, has superoxide dismutase (SOD)-like activity in vitro, and its expression aids in the cellular response to oxidative stress. However, the interplay between PrPs (PrP(C), PrP(Sc) and possibly other abnormal species), copper, anti-oxidation activity and pathogenesis of prion diseases remain unclear. In this study, we reported dramatic depression of SOD-like activity by the affinity-purified PrPs from scrapie-infected brains, and together with significant reduction of Cu/Zn-SOD activity, correlates with significant perturbations in the divalent metals contents. We also detected elevated levels of nitric oxide and superoxide in the infected brains, which could be escalating the oxidative modification of cellular proteins, reducing gluathione peroxidase activity and increasing the levels of lipid peroxidation markers. Taken together, our results suggest that brain metal imbalances, especially copper, in scrapie infection is likely to affect the anti-oxidation functions of PrP and SODs, which, together with other cellular dysfunctions, predispose the brains to oxidative impairment and eventual degeneration. To our knowledge, this is the first study documenting a physiological connection between brain metals imbalances, the anti-oxidation function of PrP, and aberrations in the cellular responses to oxidative stress, in scrapie infection.

Animals↗
PubMed2001

[Formation of specific complex of SV40 large tumor antigen and p53 in human brain tumors].

OBJECTIVE: To study the interaction of SV40 early region gene coding product, the large tumor antigen(Tag) with tumor suppressor p53 in human brain tumorigenesis. METHODS: Tag was detected by immunoprecipitation and Western blot in 43 cases of human brain tumors and 5 cases of normal human brain tissues. Tag-p53 specific complex was screened in 18 Tag positive cases. RESULTS: Tag was found in all of 5 ependymomas and 2 choroid plexus papillomas, as well as in pituitary adenomas (5/6), astrocytomas (7/10), meningiomas (4/6), glioblastomas multiforme (3/5) and medulloblastomas (2/5). None of the 5 normal brain tissues were positive for Tag, nor were 3 oligodendrogliomas and 1 pineocytoma. Tag-p53 complexes were found in all of 18 Tag positive cases. CONCLUSION: SV40 Tag can form a specific complex with p53 in human brain tumors, the inactivation of p53 due to the formation of Tag-p53 complex may be one of the important mechanisms of human brain tumorigenesis.

Antigens, Polyomavirus Transforming↗
PubMed2001

[Audiological findings of the aging across the urban and rural of Suzhou].

OBJECTIVE: To determine the epidemiological characteristics of old people's hearing. METHOD: Questionnaires, physical examination, audiometry and bio-chemical tests were performed on the elders above 60 years old in part of the urban and rural area of Suzhou with random sample survey. RESULT: A total of 1,040 individuals was investigated, among which 505 were from urban, and 535 were from rural. 33 of 505 senior citizen (6.53%) were nososacusis, 282 (55.84%) were presbycusis and 21 (4.16%) were noise-induced deafness; In the rural area, 35 of 535 (6.54%) were nososacusis, 232 (43.36%) were presbycusis, and 4 (0.75%) were noise deafness. There was significant difference of the incidence of presbycusis between urban and rural. The audiometric thresholds chart manifested that the threshold elevated with age increasing especially in high-frequency. CONCLUSION: The etiology of hearing loss of elders was mainly due to presbycusis. The higher incidence of psychotic disorder in urban probably caused a correspondingly higher incidence of presbycusis. So the prevention and cure of some age-induced diseased (e.g. hypertension, arteriosclerosis and diabetes) may be helpful to release and improve presbycusis.

Aged↗
PubMed2001

[Diagnosis and treatment of horizontal canal benign paroxysmal positional vertigo].

OBJECTIVE: To explore effective methods for the diagnosis and treatment of horizontal-canal benign paroxysmal positional vertigo (HC-BPPV). METHODS: Medical records from nine patients with HC-BPPV, treated between July 1996 and March 2000, were retrospectively analyzed. Data of complete history, audiograms, positional tests and neuro-otological examinations were collected. All patients were treated with a particle repositioning maneuver called the "barbecue rotation" which starts with the patient in the supine position and consists of three 90-degree head rotations towards the unaffected ear. RESULTS: HC-BPPV was characterized by brief attacks of intense vertigo that were induced mainly by rolling over in bed (9/9) and turning the head to either side while upright (5/9). In most cases, rotation to the pathological side from supine position caused a very intense horizontal nystagmus beating towards the undermost ear. Findings such as latency and fatigability, which are common features of posterior-canal BPPV (PC-BPPV), were not present. After the barbecue rotation, all patients had immediate and sustained relief of their attacks during the 4 to 15 months' follow up. CONCLUSION: HC-BPPV is different from PC-BPPV and other vertiginous diseases in typical presentations and positional testing results. The barbecue rotation is a successful method for curing the disorder.

Adult↗
PubMed2001

[A preliminary study of a hearing screening model for newborn].

OBJECTIVE: To search for a hearing screening model for newborn and to investigate the prevalence of newborn hearing loss in our country. METHODS: The distortion product otoacoustic emissions (DPOAE) was used to test the hearing in 2,998 of 3,075 newborns before discharge. Otoacoustic emissions (OAE) was again used for cases failed in the hospital screening 4 weeks later. Those cases failed in both screening steps were finally tested by auditory brainstem response (ABR). All infants failed in ABR test received diagnostic evaluation audiologically to identify the category and degree of hearing loss. The pass criterion of DPOAE was defined as signal-noise-ratio (SNR) exceeding 6 dB in 4 of 5 frequencies between 1.5-6 kHz. The pass criterion of ABR was the presence of wave V in response to 35 dB nHL click stimuli. RESULTS: The OAE screening in the hospital showed that 2,710 (90.4%) newborns passed the first test. Two hundred and sixty three of 288 newborns passed the second OAE screening after one month. Six of 25 infants failed in ABR test were eventually identified to be hearing impaired. CONCLUSION: Two-stages screening, combining OAE and ABR tests, may be an ideal model for newborn hearing screening. The prevalence of congenital hearing loss is similar to that reported in the literature.

Evoked Potentials, Auditory, Brain Stem↗
PubMed2000

Identification of TNFRSF1B as a novel modifier gene in familial combined hyperlipidemia.

Familial combined hyperlipidemia (FCHL) is the most commonly inherited hyperlipidemia in man, with a frequency of +/-1% in the general population and approximately 10% in myocardial infarction survivors. A genomic scan in 18 Dutch FCHL families resulted in the identification of several loci with evidence for linkage. One of these regions, 1p36.2, contains TNFRSF1B which encodes one of the tumor necrosis factor receptors. An intron 4 polymorphic CA-repeat was used to confirm linkage to FCHL. Linear regression analysis using 79 independent sib pairs showed linkage with a quantitative FCHL discriminant function (P = 0.032), and, borderline, with apolipoprotein B levels (P = 0.064). Furthermore, in a case-control study, association was demonstrated since the overall CA-repeat genotype distribution was significantly different among 40 unrelated FCHL patients and 48 unrelated healthy spouse controls (P = 0.029). This difference was due to a significant increase in allele CA271 homozygotes in the FCHL patients (P = 0.019). Mutation analysis of exon 6 in 73 FCHL family members demonstrated the presence of a single nucleotide polymorphism with two alleles, coding for methionine (196M) and arginine (196R). Complete linkage disequilibrium between CA267, CA271 and CA273 and this polymorphism was detected. In 85 hyperlipidemic FCHL subjects, an association was demonstrated between soluble TNFRSF1B plasma concentrations and the CA271-196M haplotype. In conclusion, TNFRSF1B was found to be associated with susceptibility to FCHL. Our data suggest that an as yet unknown disease-associated mutation, linked to alleles 196M and CA271, plays a role in the pathophysiology of FCHL.

Adult↗
PubMed2000

Expression and significance of urokinase type plasminogen activator gene in human brain gliomas.

BACKGROUND AND OBJECTIVES: Urokinase type plasminogen activator (uPA) regulates a variety of processes involved in tissue morphogenesis, cell differentiation, migration and invasion. We analyzed the available informations to better interpret the pathogenetic relationship between uPA activity and the malignant biological behavior of human brain gliomas. METHODS: We retrospectively studied the presence and distribution of uPA in human brain gliomas by Northern blot hybridization and immunohistochemical methods in 43 cases of brain gliomas and 5 cases of normal brain tissues. RESULTS: All tissues expressed 2.5 kb transcripts of uPA mRNA. The uPA mRNA levels were significantly higher in high-grade gliomas than in low-grade gliomas and normal brain tissues (P < 0.01). Levels of uPA mRNA expression in tumor tissues with recurrence in 18 months postoperatively and survival period less than 3 years were significantly higher than counterparts (P < 0.01). The distribution of uPA protein in the immunoreactivity was mainly in tumor cells and microvascular endothelial cells of glioblastomas and anaplastic astrocytomas, localizing at cytoplasms, especially near sites of vascular proliferation and at the leading edges of tumors. CONCLUSIONS: High expression of uPA gene is associated with the malignant progression of gliomas and demonstrates a high level of correlation with the recurrence and invasive behaviors of high grade gliomas.

Adolescent↗
PubMed2000

Fine-needle aspiration of a metaplastic breast carcinoma with extensive melanocytic differentiation: a case report.

Metaplastic carcinomas of the breast are uncommon breast tumors with aberrant cellular differentiation, most commonly showing ductal, squamous, and mesenchymal components. A breast carcinoma composed of both epithelial and melanocytic differentiation is rare, with only four previously reported cases in the literature. We present the fifth reported case, where the diagnosis was suggested by fine-needle aspiration (FNA) and later confirmed after the surgical specimen was excised. Histologically, this neoplasm revealed multidirectional differentiation, consisting primarily of squamous and melanocytic cell types, with focal glandular and osseous metaplasia. Based on the morphologic, immunohistochemical, and ultrastructural findings, we conclude that such tumors fall within the spectrum of metaplastic carcinomas of the breast. We believe that this case will further contribute to the understanding of this enigmatic tumor.

Antigens, Neoplasm↗
PubMed2000

Bax expressed from a herpes viral vector enhances the efficacy of N,N'-bis(2-hydroxyethyl)-N-nitrosourea treatment in a rat glioma model.

N,N'-bis(2-hydroxyethyl)-N-nitrosourea (BCNU) is a commonly used agent for treatment of malignant gliomas. The mechanisms of cell death and the role of Bcl-2 and Bax in a BCNU-treated rat glioma cell line were investigated. Our results indicate that apoptosis occurs only at a high concentration of BCNU with elevated levels of Bax and a reversed ratio of Bax/Bcl-2. Overexpression of Bax delivered by a herpes simplex viral vector in combination with BCNU chemotherapy enhanced the efficacy of BCNU in a rat glioma model. These findings suggest that conventional treatment with BCNU may be combined with gene therapy that delivers a bax gene into the glioma cells to achieve a high level of Bax, facilitating BCNU-induced cytotoxicity.

Animals↗