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Biomedical subjects

G M Marley

Publications and source records attributed to G M Marley.

11 recordsLinked to original sources
PubMed1999

Measurement of urinary N-acetyl-beta-D-glucosaminidase to assess renal ischemia during laparoscopic operations.

BACKGROUND: Oliguria during laparoscopy is a well-documented phenomenon of unknown etiology. Experimental evidence suggests that renal perfusion is reduced during pneumoperitoneum. N-acetyl-beta-D-glucosaminidase (NAG), which is present in renal tubular cells, is released into the urine in response to tubular insults. In this study, urinary NAG was measured before and after procedures to assess for ischemic renal injury. METHODS: A total of 31 patients underwent laparoscopic procedures while 28 patients had conventional surgery. Urine was obtained first at the time of preoperative Foley catheter placement and later during the recovery room stay. NAG levels were measured and indexed to urinary creatinine. RESULTS: Operative time for the laparoscopy group was 105 min (range, 15-255); for the conventional group, it was 179 min (range, 75-385) (P < 0.05). No differences were noted between pre- and postoperative NAG levels or between the groups. There was no correlation between urinary NAG levels and operative time. CONCLUSION: Pneumoperitoneum is not associated with a change in the urinary concentration of NAG. This finding suggests that there is no significant renal tubular injury associated with laparoscopic surgery.

Acetylglucosaminidase↗
PubMed1999

Interleukin-8 serum levels in patients with benign prostatic hyperplasia and prostate cancer.

OBJECTIVES: Using arbitrarily primed polymerase chain reaction (AP-PCR) ribonucleic acid (RNA) fingerprinting, we discovered a messenger RNA (mRNA) that encoded the cytokine interleukin-8 (IL-8) that was up-regulated in the peripheral blood leukocytes (PBLs) of patients with metastatic prostate cancer (CaP) compared with similar cells from healthy individuals. We compared the total prostate-specific antigen (PSA) levels, the free/total (f/t) PSA ratios, and the immunoreactive IL-8 serum concentrations in patients with either biopsy-confirmed benign prostatic hyperplasia (BPH) or CaP. METHODS: The sera from 35 apparently healthy normal volunteers and 146 patients with biopsy-confirmed BPH and CaP obtained from two academic centers were retrospectively examined to determine the serum levels of IL-8, total PSA (tPSA), and the f/t PSA ratio. Logistic regression and trend analysis statistical methods were used to assess the results. RESULTS: Normals (n = 35), BPH patients (n = 53), patients with clinical Stages A to C CaP (n = 81), and patients with metastatic CaP (n = 1 2) had mean levels of IL-8 of 6.8, 6.5, 15.6, and 27.8 pg/mL, respectively. The IL-8 serum concentrations correlated with increasing CaP stage and also differentiated BPH from clinical Stages A, B, C, or D CaP better than tPSA and performed similarly to the f/t PSA ratio. The combination of the IL-8 levels and f/t PSA ratios using multivariate logistic regression analysis distinguished BPH from Stages A, B, C, or D CaP or only Stages A and B with a receiver operating characteristic area under the curve of 89.8% and 87.5%, respectively (P <0.0001). CONCLUSIONS: The IL-8 serum concentration in our clinically well-defined patient sample was independent of the f/t PSA ratio as a predictor of CaP. When test samples are controlled for extraneous clinical origin of inflammation or infection, the combination of the IL-8 and f/t PSA assay results may offer an improved approach for distinguishing BPH from CaP.

Adult↗
PubMed1996

Free and complexed prostate-specific antigen serum ratios to predict probability of primary prostate cancer and benign prostatic hyperplasia.

OBJECTIVES: Ratios of free to total prostate-specific antigen (f/t PSA ratio) improved differentiation of benign prostatic hyperplasia (BPH) from prostate cancer (CaP). Using sera obtained at least 1 month prior to biopsy-confirmed diagnosis and logistic regression adjusted for disease prevalence, probability curves are constructed to predict the presence of CaP. METHODS: The patient population included 122 (44%) BPH sera and 155 (56%) prostate carcinoma sera collected prior to any therapy. The total PSA range = 2.0-20.0 ng/mL; median age = 69 years. External reference standards for both free and total PSA assays were used to standardize the assays and correct the ratio. Probability curves and tables for cancer incidence were formulated for a subset of the total test population (total PSA range = 2.0-10.0 ng/mL; 98 BPH, 118 CaP patients) by using logistic regression and prior cancer prevalence statistics derived from a published patient screening study. RESULTS: Median f/t PSA ratios were 0.18 and 0.12 in the overall sample and 0.19 and 0.12 in the subset for BPH and CaP, respectively (P = 0.0001). The median total PSA concentrations for BPH and CaP were 5.8 and 6.7 ng/mL when total PSA range = 2.0-20.0 ng/mL and were 4.9 and 5.9 ng/mL when total PSA range = 2.0-10.0, respectively. CONCLUSIONS: Cancer probability curves were constructed to help guide decisions concerning biopsy and other aspects of prostate cancer disease management. Further validation of this approach in another series of patients is necessary and is planned.

Adult↗
PubMed1996

Development of secondary structure, growth characteristics and cytogenetic analysis of human transitional cell carcinoma xenografts in scid/scid mice.

PURPOSE: The growth of human bladder transitional cell carcinoma (TCC) in scid/scid mice was examined. MATERIALS AND METHODS: Cystocopically obtained TCC biopsies were implanted in scid/scid mice, and successful xenografts were compared with original tumors for growth and genetic characteristics. RESULTS: Low grade papillary tumors formed fluid-filled pseudobladders lined with malignant urothelium and papillary fronds containing fibrovascular cores recruited from the murine host. High grade xenografts grew without these secondary structures. When compared with the patient tumors, xenograft growth fractures, as measured by proliferating cell nuclear antigen, p53 expression and ploidy, were similar in each. CONCLUSIONS: The scid/scid xenografts maintain phenotype and architecture. This model may be useful for studying factors determining tumor grade, angiogenesis and tissue organization.

Animals↗
PubMed1995

Long-term primary culture of epithelial cells from rainbow trout Oncorhynchus mykiss) liver.

Long-term primary cultures of epithelial cells from rainbow trout (Oncorhynchus mykiss) liver have been established. Nearly homogenous (> 97%) populations of hepatocytes were placed into primary culture and remained viable and proliferative for at least 70 d. In addition to hepatocytes, proliferative biliary cells persisted in the cultures for at least 30 d. Finally, a third type of epithelial cell, which we have termed a "spindle cell," consistently appeared and proliferated to confluence in these cultures. The confluent cultures of spindle cells were successfully subcultured and passaged. The initial behavior, growth, and optimization of serum and media requirements for these cells is described. All three cell types proliferated as measured by thymidine incorporation, autoradiography, proliferating cellular nuclear antigen analysis, and propidium iodine staining. Further efforts to characterize the cells included western blotting and immunohistochemical staining with antibodies to cytokeratins previously reported in fish liver. From these data, it appears that all three cell populations are epithelial in nature. Furthermore, significant changes in actin organization, often indicative of transformation or pluripotent cells, were observed with increased time in primary culture.

Actins↗
PubMed1994

Quantitative nuclear morphometry, Markovian texture descriptors, and DNA content captured on a CAS-200 Image analysis system, combined with PCNA and HER-2/neu immunohistochemistry for prediction of prostate cancer progression.

One hundred and twenty-four localized prostate cancer patients operated on at Johns Hopkins Hospital (JHH) since 1975 were identified. The sample was optimized for evaluation of prostate cancer progression. Based upon accurate clinical histories, these radical prostatectomy patients included 50 progressors and 74 non-progressors using appearance of serum PSA as an indication of recurrence (mean follow-up = 8.6 +/- 1.8 years, range 7-15 years). All patients included in the study had no involvement of their seminal vesicles or lymph nodes at the time of prostatectomy. Average time to progression was 3.6 +/- 2 years, range of 1-8 years. Using paraffin-embedded specimens, several five micron sections were cut and placed on Probe-On slides; one slide was H&E-stained and the other was Feulgen-stained. The H&E and Feulgen-stained slides were screened and "dotted" by pathologists at JHH and CytoDynostics, Inc. A CAS-200 Image analysis system (Cell Image Systems, Elmhurst, IL) equipped with a Cell Measurement Program version 1.2 beta, was used to capture the Feulgen-stained images and to perform the calculations. From the "dotted" areas, 150 cancer cells were selected for measurement of DNA content and 27 nuclear morphometric shape and size factors, including 21 Markovian chromatin texture variables. Additional sections were used for immunochemistry staining with an alkaline phosphatase streptavidin-biotin complex stain to detect and quantitate cancer cells binding monoclonal antibodies directed against proliferating cell nuclear antigen (PCNA) and HER-2/neu antigen. All data were entered into a statistical program (STATA) for further analysis and univariate and multivariate statistical analysis was performed using logistic regression and its stepwise variant. The biomarkers of greatest utility to detect progressors when analyzed univariately included post-operative Gleason score (p = < 0.0001), HER-2/neu antigenicity (p = 0.0147), CAS-200 DNA ploidy (p = 0.008), and twelve Markovian nuclear texture and shape features (p = < 0.0001), whereas PCNA (p = 0.160) failed. The optimal set of nuclear morphometry progression tumor features were selected using backward stepwise logistic regression estimate analysis which drops variables due to collinearity. Although post-operative Gleason score is a strong univariate predictor of progression, DNA ploidy and HER-2/neu contributed significantly to further stratification of higher risk groups within the low Gleason score subpopulation. The best Markovian features combined with post-operative Gleason score generated sensitivity = 90%, specificity = 96%, positive predictive value = 94%, negative predictive value = 93% and the area under the receiver operator curve was 0.975.

Biomarkers, Tumor↗
PubMed1989

Potentiation of interferon induction of class I major histocompatibility complex antigen expression by human tumor necrosis factor in small cell lung cancer cell lines.

The response of class I major histocompatibility complex antigen expression to in vitro administration of interferon and tumor necrosis factor alpha (TNF-alpha) was measured using class I major histocompatibility complex-deficient small cell lung cancer cell lines. Significant induction also was observed using gamma interferon (IFN-gamma) alone, whereas TNF-alpha alone yielded only modest induction. Classic small cell lung cancer cell lines NCI-H146 and NCI-H209 best demonstrated synergistic HLA and beta 2-microglobulin antigen induction with IFN-gamma and TNF-alpha with the following dose schedule: 3-6 days of TNF-alpha (200 units/ml) followed by 48 h of IFN-gamma (100 IU/ml). Induction was quantitated using an 125I-Protein A radioimmunoassay. Synergistic induction of the HLA and beta 2-microglobulin surface antigens on NCI-H146 was also possible with alpha interferon and TNF-alpha but required a higher concentration of the interferon, i.e., 3-6 days of TNF-alpha (200 units/ml) followed by 48 h of alpha interferon (1000 units/ml). Small cell lung cancer cell line NCI-H146 was further studied for expression of major histocompatibility complex messenger RNA using the optimal doses and sequence of addition of IFN-gamma and TNF-alpha as indicated above. A significant induction with IFN-gamma alone and synergistic induction with both IFN-gamma and TNF-alpha was quantitated for both HLA-A2 and beta 2-microglobulin transcripts using Northern blot analysis. Incubation with relatively low subcytotoxic doses of IFN-gamma and TNF-alpha also resulted in a marked synergistic decrease in c-myc message.

Animals↗
PubMedDate not supplied

Clofazimine binding studies with deoxyribonucleic acid.

1. The antileprosy drug, clofazimine, formed stable complexes with DNA and transfer RNA. A quantitative study was made of the spectral red shifts that occurred when clofazimine interacted with DNA. The red shift appeared specific for clofazimine binding to nucleic acid polymers. 2. The degree of clofazimine interaction with DNA was related to the G+C content of the DNA strand. As compared to the human strand, clofazimine interacted with the mycobacterial strand to give a larger red shift which was consistent with the increased G+C content of mycobacterial DNA. 3. It was found that clofazimine interacted with the synthetic single-stranded polynucleotide, poly G, whereas little interaction occurred withpoly A, poly C, or poly U. It was concluded that the guanine base region was a predominant site of clofazimine binding to DNA. 4. No evidence was found to indicate that clofazimine underwent intercalative binding between the base pairs of DNA. 5. It was proposed that clofazimine underwent binding along the minor groove region of DNA at appropriate base sequences which contain guanine. The resultant effect would inhibit template function of the DNA strand.

Binding Sites↗