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Biomedical subjects

J Qian

Publications and source records attributed to J Qian.

At least 181 records · Page 10Linked to original sources
PubMed1996

Transurethral enzymatic ablation of the prostate: canine model.

OBJECTIVES: The purpose of this study was to investigate the toxicity and potential usefulness of transurethral prostatic injection of a collagenase-based solution in treating benign prostatic hyperplasia in dogs. METHODS: The injected solution contained collagenase, hyaluronidase, Triton X-100, and gentamicin. Twenty-one dogs were randomly divided into three groups for transurethral prostatic needle injection: two treatment groups were observed for 6 and 12 weeks and a control group was observed for 12 weeks. Laboratory studies, clinical monitoring, and complete postmortem examination were performed in all animals. RESULTS: Gross hematuria was noted in all dogs for a mean of 4 days after injection. No significant postoperative morbidity was noted. There were no significant differences in the values of laboratory tests among the three groups except for a mean increase in serum level of aspartate transaminase for treatment groups on postoperative day 1; this resolved by postoperative day 7. Histologically, all treated prostates had stromal atrophy and cystic acinar dilation involving about 30% of the gland without extraprostatic extension of these changes. The urethra, bladder, rectum, testicles, kidney, liver, and lungs were normal and intact in all animals. CONCLUSIONS: Transurethral injection of this enzyme solution creates a predictable, favorable histologic response in the canine prostate. The procedure appears safe and warrants further investigation for treatment of human benign prostatic hyperplasia.

Animals↗
PubMed1996

Potential markers of aggressiveness in prostatic intraepithelial neoplasia detected by fluorescence in situ hybridization.

OBJECTIVE: High-grade prostatic intraepithelial neoplasia (PIN) represents the most likely precursor of prostatic adenocarcinoma. In this review, we discuss the utility of different techniques of interphase fluorescence in situ hybridization (FISH) in evaluating the genetic association between PIN and adenocarcinoma. METHODS AND RESULTS: Although the proportion of PIN and prostatic carcinoma foci that have chromosomal anomalies is similar, foci of carcinoma often have more alterations. This supports the hypothesis that PIN is a precursor of carcinoma. In some prostates, however, PIN foci have more alterations than matched carcinoma foci, suggesting that PIN foci can sometimes undergo more extensive chromosome evolution than carcinoma foci. Gain of chromosome 8 is the most common numerical alteration in prostatic carcinoma and PIN foci, and is associated with increasing cancer stage and grade. Thus, genes on chromosome 8 may play a role in the initiation and progression of prostatic carcinoma. One primary tumor focus usually shares chromosomal anomalies with associated lymph node metastases, implying that only one primary lesion acquires genetic alterations that allow it to escape the prostate. CONCLUSIONS: PIN and prostatic carcinoma have similar genetic changes. This supports the hypothesis that PIN is often a precursor of carcinoma. Genes on chromosome 8 may play a role in both initiation and progression of prostatic carcinoma.

Adenocarcinoma↗
PubMed1996

Prospective analysis of the incidence of ipsilateral adrenal metastasis in localized renal cell carcinoma.

PURPOSE: The incidence of ipsilateral adrenal metastasis in renal cell carcinoma was evaluated in a prospective fashion to understand more fully the natural history of this disease. MATERIALS AND METHODS: During a 15-month period 128 radical nephrectomies were performed for stages T1 to T3bN0M0 renal cell carcinoma at our institution. Of these specimens 100 adrenal glands were of sufficient integrity to allow for thin sectioning. RESULTS: Among the 100 adrenal glands 4 adrenal lesions were discovered (2 metastatic renal cell carcinomas and 2 benign adrenal lesions). All 4 lesions were identified preoperatively by computerized tomography or magnetic resonance imaging. CONCLUSIONS: Our prospective investigation demonstrates that the rate of ipsilateral adrenal metastasis from renal cell carcinoma is approximately 2%, and suggests that when the ipsilateral adrenal gland is well visualized and of normal integrity on preoperative magnetic resonance imaging or computerized tomography adrenal sparing nephrectomy may be considered a viable treatment option.

Adrenal Gland Neoplasms↗
PubMed1996

Prediction of capsular perforation and seminal vesicle invasion in prostate cancer.

PURPOSE: Capsular perforation and seminal vesicle invasion are unfavorable prognostic factors in prostate cancer. Accurate preoperative prediction of these factors would be clinically useful for planning treatment, especially in patients being considered for radiation therapy, nerve sparing radical prostatectomy and watchful waiting. However, current methods are imprecise at predicting the presence and extent of these factors. We determined which combination of commonly available preoperative variables provides the best prediction of capsular perforation and seminal vesicle invasion of patients with clinically localized prostate cancer. MATERIALS AND METHODS: We reviewed the preoperative medical records and biopsy findings from 314 patients with clinical stages T1cN0M0 to T2cN0M0 cancer who underwent radical retropubic prostatectomy and bilateral pelvic lymphadenectomy between September 1991 and June 1993. Radical prostatectomy specimens were embedded and evaluated by whole mount sections. RESULTS: Capsular perforation was observed in 104 patients (33.1%) and seminal vesicle invasion was noted in 46(14.6%). Preoperative variables predictive of capsular perforation and seminal vesicle invasion on univariate analysis were serum prostate specific antigen (PSA) concentration, clinical, stage, Gleason primary and secondary patterns, Gleason score, nuclear grade, perineural invasion and percent cancer in the biopsy specimens. On multivariate analysis, independent prognostic factors for capsular perforation and seminal vesicle invasion were PSA, Gleason score and percent cancer in the biopsy specimens. CONCLUSIONS: The combination of serum PSA concentration, Gleason score and percent cancer in the biopsy specimens provides the best prediction of capsular perforation and seminal vesicle invasion. Models based on this combination of factors may be clinically use to stratify patients for nonoperative treatment.

Adenocarcinoma↗
PubMed1996

Fluorescence in situ hybridization analysis of renal oncocytoma reveals frequent loss of chromosomes Y and 1.

PURPOSE: Cytogenetic studies of a small number of renal oncocytomas have indicated that loss of chromosomes 1 and Y may be involved in the pathogenesis of this tumor. To evaluate these observations further we selected paraffin embedded renal oncocytoma specimens from 20 male and 10 female patients for fluorescence in situ hybridization analysis. MATERIALS AND METHODS: Isolated nuclei were prepared from paraffin embedded specimens, and fluorescence in situ hybridization was performed with enumeration probes for chromosomes 1, 12, X and Y. RESULTS: Tumors from 10 male (50%) and 4 female (40%) patients demonstrated chromosomal alterations. Loss of chromosome Y was observed in specimens from all 10 male patients, and loss of chromosome 1 or gain of chromosome 12 was noted in 5 and 2 of these specimens, respectively. Of the 4 female patients with chromosomal abnormalities 2 had loss of chromosome 1, 1 had gain of chromosome 1 and 1 had gain of chromosome 12. CONCLUSIONS: Our results confirm that loss of chromosomes Y and 1 is common in renal oncocytoma, and that the alterations are probably involved in the pathogenesis of this tumor.

Adenoma, Oxyphilic↗
PubMed1996

Comparison of fluorescence in situ hybridization analysis of isolated nuclei and routine histological sections from paraffin-embedded prostatic adenocarcinoma specimens.

Fluorescence in situ hybridization (FISH) is a powerful tool for quantitative analysis of chromosomes and genes and can be applied in a variety of specimens, including cell cultures, isolated nuclei from fresh and fixed tissues, and histological tissue sections. However, the results of FISH analysis of isolated nuclei in prostate cancer have not been previously compared with those from histological sections from the paraffin-embedded tissue blocks. To compare these methods, we studied isolated nuclei derived from 50-microns sections and adjacent 5-microns tissue sections from 10 cases of benign nodular hyperplasia of the prostate and 16 cases of prostatic carcinoma. FISH analysis employed centromere-specific probes for chromosomes 7, 8, 11, and 12. In benign tissue, the percentage of nuclei with three or more signals for chromosomes 7, 8, 11, and 12 was less than 3% for both isolated nuclei and tissue sections. However, the percentage of nuclei with no and one signals was less than 8% for isolated nuclei and more than 24% for tissue sections. In prostatic carcinoma, numeric chromosomal anomalies were found in 75% of cases by both FISH methods. However, isolated nuclei had more chromosomal tetrasomy than tissue sections (mean, 9.2 to 11.0% versus 5.1 to 5.6%, respectively). Conversely, intratumor heterogeneity of chromosomal anomalies was identified in 5 cases by FISH analysis of tissue sections but not in isolated nuclei. Cancer ploidy analysis by FISH correlated well with ploidy analysis by flow cytometry, although FISH was more sensitive for aneuploidy. We conclude that FISH analysis of isolated nuclei and histological tissue sections from paraffin blocks are reliable methods for detection of chromosomal anomalies in archival tissue of prostate cancer, although each method has advantages and disadvantages.

Adenocarcinoma↗
PubMed1996

[Observation on nasal mucociliary ultrastructure of ostiomeatal complex].

Functional endoscopic sinus surgery (FESS) was performed on 35 patients who suffered. from chronic nasosinusitis. All patients recovered six months after operation. During FESS, 10 specimens of pathological mucosa were obtained near the ostium of maxillary sinus. Scanning electron microscope and transmission electron microscope were used to observe pathological changes of mucociliary ultrastructure. The results indicate that FESS is easier, safer and more practicable surgery than traditional one. The pathological changes observed include loss of cilia, disorientation, short cilia and tubular abnormalities. These ultrastructural changes are believed to be the results of long-term inflammation in the nose and paranasal sinuses.

Adult↗
PubMed1996

[Analysis of extracorporeal circulation on ventricular septal defect complicated by severe pulmonary hypertension in 53 children].

Extracorporeal circulation and myocardial protection in 53 children with ventricular septal defect associated with severe pulmonary hypertension were reported. The average aortic cross-clamping time was 45.5 minutes. The hearts were defibrillated spontaneously in 35 patients. We emphasized that full understanding of the pathophysiological characteristics of ventricular septal defect associated with severe pulmonary hypertension in children is fairly important to the use of various extracorporeal circulation techniques during surgical intervention.

Child↗
PubMed1995

Chromosomal anomalies in prostatic intraepithelial neoplasia and carcinoma detected by fluorescence in situ hybridization.

The pathogenetic relationship between high-grade prostatic intraepithelial neoplasia (PIN), prostatic carcinoma, and metastases is poorly understood. We used fluorescence in situ hybridization (FISH) with centromere-specific probes for chromosomes 7, 8, 10, 12, and Y to evaluate numeric chromosomal anomalies in PIN (68 foci), localized prostatic carcinoma (78 foci), and lymph node metastases (8 foci) in 40 whole-mount radical prostatectomy and pelvic lymphadenectomy specimens. Chromosomal anomalies were found in 50, 51, and 100% of the foci of PIN, carcinoma, and metastases, respectively. The mean numbers of abnormal chromosomes per focus were 0.66 in PIN, 1.09 in carcinoma, and 3.75 in metastases. The most frequent anomaly in PIN was a gain of chromosome 8 (32% of foci), followed by gains of chromosomes 10 (13%), 7 (10%), 12 (4%), and Y (4%). The most frequent anomalies in foci of carcinoma were gains of chromosomes 7 and 8 (28% and 30% of foci, respectively), followed by gains of chromosomes 10 (23%), 12 (9%), and Y (9%). There was a positive correlation of the gain of chromosome 8 with the pathological stage and Gleason score (both P < 0.05). Usually, carcinoma foci contained more anomalies than paired PIN foci, but five prostates contained one or more foci of PIN with more anomalies than carcinoma. Among the cases with metastases, usually one or more foci of the primary tumor shared chromosomal anomalies with the matched metastases. Our results indicate that PIN and prostatic carcinoma foci have similar proportions of chromosomal anomalies, but foci of carcinoma usually have more alterations. This observation supports the hypothesis that PIN is often a precursor of carcinoma, although there are some carcinoma foci that have few or no apparent chromosomal alterations, whereas concurrent PIN foci have multiple alterations. A gain of chromosome 8 was the most common numerical alteration and was associated with increasing cancer stage and grade, suggesting that it may play a role in the initiation and progression of prostatic carcinoma. Usually, one or more foci of the primary tumor shared chromosomal anomalies with associated lymph node metastases, suggesting that, often, just a single focus of carcinoma gives rise to metastases.

Aged↗
PubMed1995

Immunoblot cross-reactivity of factor VIII inhibitors with porcine factor VIII.

Porcine factor VIII has been used successfully to treat factor VIII inhibitor patients whose plasmas have minimal cross-reactivity to porcine factor VIII. However, some inhibitor plasmas do inhibit porcine factor VIII, and the extent of procoagulant inhibition often increases after treatment with porcine factor VIII. Because there is no information about the porcine factor VIII epitopes with which these antibodies react, we have compared the immunoblot and enzyme-linked immunosorbent assay (ELISA) reactivities with porcine and human factor VIII for 20 inhibitor plasmas (11 from hemophilia A patients and 9 autoantibodies). Immunoblots identified binding to porcine factor VIII for only 2 of the 12 plasmas from patients who had not received porcine factor VIII, but this reactivity could not be predicted from the inhibitor titer to porcine factor VIII. Immunoblot reactivity with porcine factor VIII was detected for 7 of 8 inhibitor plasmas from patients who had been previously treated with porcine factor VIII, and the strength of this reactivity was generally related to the inhibitor titer. Of the 5 plasmas that were immunoblot positive with the porcine factor VIII A2 domain, 4 had inhibitor titers greater than 45 Bethesda units when tested with porcine factor VIII, whereas only 1 of 15 of the other plasmas had this level of inhibitor activity with porcine factor VIII. In contrast, immunoblot reactivity to the porcine factor VIII A1 domain did not correlate with the antiporcine VIII inhibitor titer. We also determined the effect of preincubation with human or porcine factor VIII on immunoblot reactivity. In one case, immunoblot reactivity with porcine factor VIII was absorbed with porcine, but not human, factor VIII, which is consistent with antibody formation after treatment with porcine factor VIII. In no cases did human factor VIII reduce the reactivity of inhibitor plasmas with the porcine A1 domain, suggesting that these antibodies are directed at unique porcine factor VIII determinants. The reactivity to porcine A2 in 2 plasmas probably represented cross-reactivity of similar A2 determinants, because it was absorbed by both human and porcine factor VIII. Although the ELISA assays with porcine factor VIII detected antibodies in some plasmas that could not be identified by inhibitor assay or immunoblot, the level of ELISA reactivity was generally consistent with the titers of the other assays.

Animals↗
PubMed1995

Possible proton relay pathways in cytochrome c oxidase.

As the final electron acceptor in the respiratory chain of eukaryotic and many prokaryotic organisms, cytochrome c oxidase (EC 1.9.3.1) catalyzes the reduction of oxygen to water and generates a proton gradient. To test for proton pathways through the oxidase, site-directed mutagenesis was applied to subunit I of the Rhodobacter sphaeroides enzyme. Mutants were characterized in three highly conserved regions of the peptide, comprising possible proton loading, unloading, and transfer sites: an interior loop between helices II and III (Asp132Asn/Ala), an exterior loop between helices IX and X (His411Ala, Asp412Asn, Thr413Asn, Tyr414Phe), and the predicted transmembrane helix VIII (Thr352Ala, Pro358Ala, Thr359Ala, Lys362Met). Most of the mutants had lower activity than wild type, but only mutants at residue 132 lost proton pumping while retaining electron transfer activity. Although electron transfer was substantially inhibited, no major structural alteration appears to have occurred in D132 mutants, since resonance Raman and visible absorbance spectra were normal. However, lower CO binding (70-85% of wild type) suggests some minor change to the binuclear center. In addition, the activity of the reconstituted Asp132 mutants was inhibited rather than stimulated by ionophores or uncoupler. The inhibition was not observed with the purified enzyme and a direct pH effect was ruled out, suggesting an altered response to the electrical or pH gradient. The results support an important role for the conserved II-III loop in the proton pumping process and are consistent with the possibility of involvement of residues in helix VIII and the IX-X loop.

Amino Acid Sequence↗
PubMed1995

Mucin expression in atypical adenomatous hyperplasia of the prostate.

Prostatic atypical adenomatous hyperplasia (AAH) is a small glandular proliferation that has histological similarities with well-differentiated adenocarcinoma. To determine the histochemical profile of AAH, we assessed the production of total neutral mucin, total acidic mucin, and sulfated acidic mucin in 24 cases of AAH, five cases of Gleason primary pattern 1 and 2 adenocarcinoma, and 29 cases of adjacent benign and hyperplastic prostatic tissue. All specimens were formalin-fixed transurethral resections, and the diagnosis in each was confirmed by evaluation of the keratin 34B-E12 immunoreactive basal cell layer (intact in benign and hyperplastic epithelium, fragmented in AAH, and absent in cancer). The extent of mucin staining was measured semiquantitatively in 10% increments according to the number of stained glands. Neutral mucin was found in all but two cases, and there was no apparent difference in the amount of staining in benign glands, AAH, and cancer (mean number of stained glands, 43%). Total acidic mucin was more common in AAH (63% of cases; mean, 11% of glands) and adenocarcinoma (60% of cases; mean, 30% of glands) than in benign glands (0% of cases). Similarly, nonsulfated acidic mucin was more common in AAH (63% of cases; mean, 12% glands) and adenocarcinoma (60% of cases; mean, 8% of glands) than in benign glands (0% of cases); the pattern and intensity of staining for nonsulfated acidic mucin appeared to be similar to that for total acidic mucin in AAH and cancer. These findings indicate that there is a close relationship in mucin expression between AAH and well-differentiated adenocarcinoma. Identification of acidic mucin should be used cautiously as an adjunct in the diagnosis of adenocarcinoma but is useful in separating some cases of AAH and adenocarcinoma from benign prostatic epithelium.

Humans↗
PubMed1995

Expression of stress proteins and lymphocyte reactivity in heterotopic cardiac allografts undergoing cellular rejection.

This report addresses the concept that, during rejection, the allograft undergoes a stress response which leads to an increased expression of stress proteins, also called heat shock proteins (hsp), and the recruitment and activation of hsp-reactive lymphocytes. Recent studies in our laboratory have provided evidence that hsp-reactive T-cells are present in cardiac allografts undergoing rejection. In this study, an MHC incompatible heterotopic heart allograft model (ACI into LEW) was chosen to analyse the kinetics of hsp expression during the development of rejection. Allografts and syngrafts (LEW into LEW) were harvested every day during the first 5 days post-transplant. Immunoblot analysis of proteins extracted from graft stromal tissues was done with murine monoclonal antibodies (mAb) against various mammalian hsp. Proliferation studies were done to determine hsp reactivity of graft-infiltrating lymphocytes on different days post-transplant. Three types of stressful stimuli appeared to increase hsp expression in the allograft. The first was a physiological stress secondary to the trauma of the transplant procedure and ischaemia/reperfusion injury and this would occur in allogeneic and syngeneic grafts. During the first day after transplantation, both types of grafts showed higher expression of hsp72 and grp78 and to a lesser extent, hsp60 and grp75. On the second and third day, the expression of grp78 and grp96 was higher in allografts than in syngrafts and this may reflect an immunologically mediated stress response in the allograft when infiltrating hsp-reactive lymphocytes became first detectable in the allograft. The third type of stress appeared related to the inflammatory process associated with rejection. On the fourth and fifth day post-transplant, the allografts showed strong expression of at least five proteins of lower molecular mass reacting with hsp-specific mAbs; namely, approximately 40 kDa (detected by anti-hsp60), approximately 30 kDa (by anti-hsp72), approximately 45 kDa and approximately 32 kDa (by anti-hsp72 + hsc73), and approximately 50 kDa (by anti-grp78). At that time, the allograft began to show progressive inflammatory changes and tissue damage. The appearance of lower molecular mass hsp-crossreactive proteins might reflect a degradation of hsps which had increased expression earlier during the post-transplant period. This process may generate large quantities of hsp-derived peptides which may be presented by MHC molecules to graft-infiltrating T-cells. Another interpretation of the strong expression of lower molecular bands in later allografts is that they represent other stress proteins that crossreact with antibodies against hsp60 and hsp70 family members.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1995

Chromosomal anomalies in atypical adenomatous hyperplasia and carcinoma of the prostate using fluorescence in situ hybridization.

OBJECTIVES: The genetic alterations of atypical adenomatous hyperplasia (AAH) of the prostate, a possible precursor of prostate adenocarcinoma, have not been previously investigated. METHODS: We used fluorescence in situ hybridization with centromere-specific probes for chromosomes 7, 8, 10, 12, and Y to evaluate chromosomal anomalies in atypical adenomatous hyperplasia (23 foci) and adenocarcinoma (31 foci) in 19 whole-mount radical prostatectomy specimens. RESULTS: Chromosomal anomalies were found in 2 foci (9%) of AAH and 17 foci (55%) of carcinoma. There was no relationship between the chromosomal anomalies in AAH and matched foci of carcinoma. CONCLUSIONS: These findings indicate that AAH is not obviously linked genetically to prostate cancer, although it occasionally contains chromosomal anomalies.

Adenocarcinoma↗