MicroRNA-99b inhibits NSCLC cell invasion and migration by directly targeting NIPBL.

OBJECTIVE: Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. microRNAs (miRNAs) have been confirmed as vital regulators of multiple tumors, including NSCLC. The aim of the current study was to explore the biological mechanisms of miR-99b in NSCLC progression. PATIENTS AND METHODS: NSCLC tissues and adjacent matched human non-neoplastic lung tissues used in this study were collected from 50 cases of NSCLC patients. The expression of miR-99b and NIPBL in NSCLC tissues and cell lines (A549, NCI-H460, NCI-H1299 and SPC-A1) were determined by real-time-polymerase chain reaction (qRT-PCR). The NIPBL protein level was measured by Western blot. Dual-Luciferase reporter, Western blotting and qRT-PCR were carried out to verify the potential target of miR-99b. Transwell assay was used for investigating miR-99b effect on cell migration and invasion in NSCLC cells. RESULTS: The results of qRT-PCR indicated that the expression of miR-99b was downregulated in the NSCLC tissues and cell lines. Overexpression of miR-99b could significantly inhibit the invasion and migration capacities in NSCLC cells. Furthermore, we also determined that NIPBL was a direct target of miR-99b. Additionally, we found NIPBL was implicated in the suppressive effects on NSCLC cell invasion and migration mediated by miR-99b. CONCLUSIONS: In summary, miR-99b exerted anti-tumor functions in NSCLC via regulation of NIPBL, suggesting that miR-99b/NIPBL axis may be novel biomarkers for NSCLC treatments.

[Development and prospective validation of an ischemic risk score for acute chest pain patients with normal high-sensitivity troponin I levels and without obvious ST-segment deviation].

Objective: To develop and prospectively validate a risk score for acute chest pain patients with normal high-sensitivity troponin I (hs-TnI) levels and without obvious ST-segment deviation in China. Methods: Chest pain patients admitted to the emergency department of Beijing Anzhen Hospital from September 2014 to July 2015 were enrolled. Baseline characteristics of patients met inclusion criteria including normal hs-TnI levels and without obvious ST-segment deviation were included. The endpoint (major adverse cardiovascular events) was a composite of acute myocardial infarction, percutaneous coronary intervention, coronary artery bypass graft, and all-cause death within 3 months after initial presentation. Predictors were screened and used to develop the risk score model by logistic regression analysis in a retrospective cohort. Then, the risk score model was evaluated in a prospective validation cohort. Results: The study population of derivation cohort included 1 735 consecutive chest pain patients. Finally, 1 030 eligible patients were enrolled. Multivariate regression analysis defined five independent predictors: male gender (ß=0.88); history of chest pain (ß value of moderate and high suspicion of coronary heart artery was 2.70 and 3.51 respectively); electrocardiogram (ß=0.84); ≥60 years old (ß=0.51) and ≥3 risk factors (ß=0.85).The range of weighted score was set as 0-13. The area under a receiver operating characteristic (ROC) curve was 0.75 (95%CI 0.72-0.78) in the final model. Major adverse cardiovascular events rates increased in proportion to score increase (P<0.01). The internal validity used bootstrap technique showed the same predictor factors as the final model, and its area under a ROC curve was 0.75(95%CI 0.72-0.78).MACE rates in the low risk group (score 0-3), intermediate risk group (score 4-7), and high risk group (score 8-13) were 1.3% (1/77) ,19.0% (22/116) ,and 42.2% (122/289) in the prospective validation cohort, respectively (P<0.01). Conclusion: The developed ischemic risk score is feasible for risk stratification of acute chest pain patients with normal hs-TnI and without obvious ST-segment deviation, this score might be helpful to the decision making of treatment and management strategies for these patients.

Integrated bioinformatics analyses identify dysregulated miRNAs in lung cancer.

BACKGROUND: Lung cancer is the most common cause of cancer-related death worldwide. MicroRNAs (miRNAs) play important roles in various biological processes, including cell development, proliferation, differentiation and apoptosis. MATERIALS AND METHODS: In the current study, using miRNA expression profiles from the Gene Expression Omnibus (GEO) database, we used three independent tests: Wilcox test, t-test and Fisher's exact test to investigate miRNA's involvement in lung carcinogenesis. RESULTS: Ten differentially expressed miRNAs were identified. Among them, miR-675 drew specific attention. Ingenuity pathway analysis of its target genes revealed its impact on cell death and cell cycle. It is possible that miR-675 contributes to the pathogenesis of lung cancer through its down regulation of the tumor suppressor gene RB1. CONCLUSIONS: Our results suggest miR-675 may serve as a potential therapeutic target of lung cancer.

Patient acceptance of self-sampling for human papillomavirus in rural china.

OBJECTIVE.: To test a new survey instrument and determine the acceptance and potential barriers of cervicovaginal self-sampling for high-risk human papillomavirus in rural Chinese women. MATERIALS AND METHODS.: Data from thirteen survey questions assessed acceptance of the self-sampling procedure. Pain, comprehension, and cultural beliefs were potential barriers evaluated by the survey. RESULTS.: A total of 1,560 women were surveyed. The average and mode number of steps of the self-sampling procedure recalled was 5 (out of 7). Ninety-one percent preferred performing the test at a clinic versus their home. The major barrier encountered was related to the educational level of the women. CONCLUSIONS.: The measure performed well in this population. The self-collection brush was well accepted by these women. Education is the largest hurdle to overcome in implementing a self-sampling screening program.

The onset of nonlinearity in cosmological structure.

We discuss the progression of growth of cosmological structure, from the quasilinear evolution of nearly Gaussian fluctuations on large scales into highly non-Gaussian, strongly nonlinear structure on small scales. A systematic development in perturbation theory describes the first departures from homogeneity but fails to reproduce the fully nonlinear results. Physical insight, conceptual models, and symmetries are useful in the strong clustering regime. A phenomenological model with input information from the quasilinear regime provides enticing results for the strongly nonlinear regime.

Establishment and characterization of renal cell carcinoma cell lines with multidrug resistance.

Many of the discoveries of multidrug resistance (MDR) have resulted from studies using drug-resistant cultured tumor cell lines as experimental models. To date, there has been no report on the detailed characterization of such a cell line from renal cell carcinoma (RCC). By long-term exposure of an established RCC (RCC8701) to increasing concentrations of adriamycin, we established a series of subcultures that were considerably more resistant to the cytotoxic effect of this drug. Biological morphology and cell cycles were analyzed by morphometry and flow cytometry. The chemoresistance index of cells were measured by methyl tetrazolium assay. For evaluation of the expression of MDR-related protein (MRP), mdr-1, glutathione transferase (GST-pi), and topoisomerase II mRNAs, the reverse transcription-polymerase chain reaction was used. Membranous expression of mdr-1-related p-glycoprotein was analyzed by immunofluorescence cytometry. The intracellular content of both glutathione (GSH) and glucose-6-phosphate dehydrogenase (G-6-PDH) were measured using a capillary electrophoresis method. Compared with parent cells, the resistant sublines had a slower growth rate and lower confluent density. They were smaller and mixed with giant cells in different sizes and with different numbers of nucleoli. Flow cytometric analyses showed that resistant cells had a greater percentage of cells in the G2/M phase. The resistant cells, RCC8701/ADR800, were 122 times more resistant to adriamycin and 238 times more resistant to epirubicin than the parent cells. The resistant cells also demonstrated cross-resistance to cisplatin and 5-fluorouracil. In addition to MRP, the contents of mRNA coding for mdr-1, GST-pi, and topoisomerase II in the MDR sublines were higher than in the native cell line. A higher content of cytoplasmic GSH and G-6-PDH were found in the resistant cells; however, the expression of the MDR-related membranous glycoprotein, p-glycoprotein, was not raised. The adriamycin-induced MDR sublines may be used as an experimental system for the search of a means to overcome drug resistance and elucidate possible mechanisms of acquired MDR involved in human renal cancer.

Verapamil modulation of multidrug resistance in renal cell carcinoma.

BACKGROUND AND PURPOSE: Renal cell carcinoma (RCC) is well known for its chemoresistance. The membranous p-glycoprotein (gp-170) is believed to be highly correlated with multidrug resistance (MDR) of cancer cells with energy-dependent pumping efflux of anticancer drugs. Verapamil, a calcium antagonist, inhibits the efflux function of gp-170 and cytoskeletal transportation. The aim of this study was to determine the effect of verapamil on gp-170 expression and intracellular drug accumulation in RCC tumor cells and the modulation of cytotoxicity of various chemotherapeutic drugs on native RCC cell lines and acquired MDR sublines by verapamil. METHODS: Using cultured cell lines of RCC and their MDR sublines as target cells, the effect of verapamil on gp-170 expression was analyzed by immunofluorescence flow cytometry. The influence of verapamil on intracellular drug accumulation in RCC tumor cells was measured by autofluorescence flow cytometry. The modulation of verapamil on cytotoxicity of various chemotherapeutic drugs on native RCC cell lines and acquired MDR sublines was analyzed by the methyl tetrazolium method. RESULTS: From flow cytometric measurement, the expression of gp-170 was significantly decreased in A704 and Caki-1 tumor cells after verapamil treatment. The uptake of adriamycin and maintenance of intracellular drugs were also significantly increased following verapamil treatment in RCC8701 tumor cells. These effects were sustained for as long as 8 hours after verapamil withdrawal. The cytotoxicity of adriamycin and epirubicin on RCC8701 and its MDR subline tumor cells was markedly intensified by verapamil. The verapamil modulation of cytotoxicity was in an immediate-reaction pattern and was dose-dependent, with synergistic effects. Long-term treatment was more effective than short-term treatment in RCC MDR sublines. The cytotoxicity of vinca alkaloid (vinblastine) and alkylators (carboplatin) was also enhanced by verapamil. CONCLUSIONS: These results suggest that verapamil plays an important role in the circumvention of native and acquired chemoresistance of RRC because it suppresses membranous gp-170 expression and cytoplasmic drug transportation.

Flow-cytometric measurement of cellular changes in urine: a simple and rapid method for perioperatively monitoring patients after kidney transplantation.

OBJECTIVE: In renal transplant patients having graft dysfunction, it is usually difficult to obtain the accurate diagnosis, such as acute rejection, acute tubular necrosis, infection, or cyclosporin nephrotoxicity. An accurate diagnosis can provide the proper treatment of these patients, thereby lessening the chance of kidney loss. METHODS: A total of 42 patients were enrolled. By using the flow-cytometric technique, the white cell populations of urine in these patients were analyzed and linked to their clinical course. All patients underwent sonography-guided biopsy of the transplanted kidney with a definitive diagnosis. RESULTS: When 10% lymphocytes and 15% granulocytes in urine were set as the cutoff point of a normal ratio threshold, the flow-cytometric analysis presented the highest sensitivity and the highest negative predictive rate for acute tubular necrosis. However, a lower sensitivity and positive predictive rate was found in acute rejection cases. CONCLUSIONS: Our results suggest that flow-cytometric analysis of the urinary cell population can be used as an adjunct in patient follow-up after kidney transplantation.

Effect of capsaicin on the micturition reflex in normal and chronic spinal cord-injured cats.

The effect of capsaicin (10-80 mg/kg sc) on reflex activity of the urinary bladder was examined in anesthetized normal as well as anesthetized and awake chronic spinal cord-injured (SCI) cats. In normal cats, capsaicin elicited a transient increase in the frequency of isovolumetric bladder contractions and reduced the volume threshold for inducing micturition, but did not depress the amplitude of bladder contractions or the reflex firing on bladder nerves. In anesthetized SCI cats, capsaicin depressed reflex bladder activity and firing on bladder nerves. In awake SCI cats, capsaicin initially decreased the volume threshold for inducing micturition; however, after a delay of 3-6 h the volume threshold increased and intravesical voiding pressure decreased. This effect persisted for 4-12 days. It is concluded that capsaicin-sensitive C fiber bladder afferents are not involved in initiating reflex micturition in normal cats, but play an essential role in triggering automatic micturition in chronic SCI cats. The results are consistent with the clinical data indicating that C fiber bladder afferents contribute to bladder hyperactivity and incontinence in patients with neurogenic bladder dysfunction.

Cocktail modulator mixtures for overcoming multidrug resistance in renal cell carcinoma.

OBJECTIVES: To determine the effect of various modulators on intracellular drug accumulation in renal cell carcinoma (RCC) tumor cells and the modulation of cytotoxicity of various chemotherapeutic drugs on the native RCC cell line and acquired intrinsic multidrug resistance (MDR) sublines because MDR is a major obstacle to effective chemotherapy of RCC. METHODS: The cytotoxicity of adriamycin to RCC 8701 and its MDR subline was analyzed. Fourteen MDR modulators, including calcium antagonists, protein kinase C inhibitor, glutathione transferase inhibitor, protein/peptide synthesis inhibitors, respiratory chain inhibitors, uncoupling reagent, adenosine triphosphate synthesis inhibitor, and ionophores, were examined for their MDR-reverse activity using the microplate tetrazolium test. RESULTS: The intracellular adriamycin concentration significantly increased and reached maximum 4 hours after simultaneous treatment with calcium antagonists, tamoxifen, and oligomycin. The result demonstrated that verapamil, quinidine, tamoxifen, and oligomycin had an additive effect on the cytotoxicity of adriamycin and vinblastine against RCC8701 and RCC8701/ADR800 tumor cells. RCC8701/ADR800 tumor cells were more sensitive to modulator enhancement than native cells. The enhancement was related to the dosage and treatment duration of the modulators. Further trials on simultaneous additions to cocktail mixtures of the above four modulators showed no additive or synergistic effect on cytotoxicity against RCC8701/ADR800 tumor cells. CONCLUSIONS: Calcium antagonists and tamoxifen and oligomycin can individually be an effective chemotherapy adjunct for overcoming the native drug resistance or acquired MDR in RCC. Combination regimens, however, need more study regarding timing of administration, dosage, and frequency of modulators.

Prevalence of cervical cancer and feasibility of screening in rural China: a pilot study for the Shanxi Province Cervical Cancer Screening Study.

For cervical cancer screening to be feasible in developing countries, it must be accurate, inexpensive, and easy to administer. We conducted a pilot study in rural Shanxi Province, People's Republic of China, to determine disease prevalence and study feasibility in preparation for a large-scale comparative trial of 6 screening tests. One-hundred and thirty-six nonpregnant women with no history of hysterectomy, pelvic radiation, or Papanicolaou tests were screened in a rural clinic. Ten percent of the women enrolled reported abnormal vaginal bleeding and 45% reported abnormal vaginal discharge. The tests were the Papanicolaou test (both conventional and ThinPrep), a self-administered swab test by Hybrid Capture II for high-risk human papillomavirus (HPV), a test for high-risk HPV from residual PreservCyt medium, fluorescence spectroscopy, and visual inspection of the cervix by a clinician. All women also underwent colposcopy and biopsies as the reference standard. Biopsies showed 12 of 136 women had >/= high-grade squamous intraepithelial lesions (HGSIL). Screening was completed in 5 half-day sessions, the procedures went smoothly, and local cooperation was enthusiastic. Disease prevalence in Xiangyuan and Yangcheng Counties, Shanxi Province, can be estimated at 8.8% (95% CI, 4.5% to 15.0%). Screening 1000-2000 patients would be sufficient to detect a 10% difference in accuracy between diagnostic tests. The proposed large-scale trial is feasible.

The expression of mdr-1-related gp-170 and its correlation with anthracycline resistance in renal cell carcinoma cell lines and multidrug-resistant sublines.

OBJECTIVES: To clarify the role of the membranous glycoprotein gp-170 in renal cell carcinoma (RCC) cell lines and their multidrug resistant (MDR) sublines. and to correlate gp-170 with the natural and acquired drug resistance of these cell lines to anthracyclines. MATERIALS AND METHODS: The expression of gp-170 in five cultured RCC cell lines and serial RCC8701 MDR sublines was analysed by immunofluorescent flow cytometry. The chemosensitivity of these tumour cells to the anthracycline anticancer drugs adriamycin and epirubicin was measured using the microplate tetrazolium (MTT) cytotoxicity assay, and the results correlated with gp-170 expression. RESULTS: All six natural RCC cell lines showed a variably increased expression of gp-170, with the A704 and Caki-1 cell lines the highest. In contrast, gp-170 expression increased and then was suppressed in acquired MDR sublines of RCC8701 cultured in increasing concentrations of adriamycin. The A704 and Caki-1 cells were much more resistant to adriamycin and epirubicin than the A498, ACHN and RCC8701 cell lines, in parallel with the expression of gp-170. The resistant cell line cultured long-term in 800 ng/mL adriamycin, RCC8701/ADR800, was 122 times more resistant to adriamycin and 238 times more resistant to epirubicin than the parent cell line: the pattern differed from that in native RCC cell lines and was unrelated to the expression of gp-170. CONCLUSION: Membranous gp-170 plays an important role in MDR of native RCC cell lines, while acquired MDR cells have different mechanisms of obtaining drug resistance in addition to gp-170. This phenomenon may be applicable to the clinical treatment of patients newly diagnosed with RCC or those with disease refractory to chemotherapy.

Pathogenesis of ischemia reperfusion injury of the kidney after transient renal arterial clamping in rats.

Renal function can be severely impaired through injuries sustained after both short and prolonged periods of complete ischemia. The magnitude of renal dysfunction resulting from these conditions and their reversibility depend on the duration of anoxia. In this study, we used a Sprague-Dawley rat model (5 to 7 rats in each group) to study the pathogenesis of short-term ischemia (30, 60, and 120 min)/reperfusion (2, 4, 24 h, 1 wk, and 3 wk) injury of the kidney under warm (room temperature) or cold (4 degrees C) conditions. Ischemia was induced by clamping the renal artery. Changes in kidney weight, histopathology, concentrations of serum thromboxane and leukotriene, and tissue malonyldialdehyde (MDA) concentration, numbers of apoptotic bodies, and p53 expression in the kidney were compared with those of sham-operated rats. The results showed that the immediate increase in kidney weight due to inflammatory swelling was associated with simultaneous elevation of serum thromboxane and leukotriene levels. The changes in mediator levels were closely related to the duration of ischemia and temperature. Histologic structures were preserved better when renal artery clamping was done at 4 degrees C. MDA peroxidation products from the ischemic tissue prominently increased 1 week following ischemia; this paralleled a secondary increase in leukotriene levels. Flow cytometric detection of p53 oncoprotein showed a marked increase at 1 week following ischemia, which was accompanied by the development of apoptotic bodies in ischemic tissues. These changes were also closely related to the ischemic time and temperature during ischemia. This animal model may be useful for future studies of the prevention of ischemia/reperfusion injury of the kidney and for selection of effective antioxidants.

Characterization and modulation of transitional cell carcinoma cell lines with acquired multidrug resistance.

OBJECTIVES: To characterize in vitro drug-induced multidrug resistance (MDR) in transitional cell carcinoma (TCC) cell lines, and to elucidate the possible mechanisms of acquired MDR and their modulation. MATERIALS AND METHODS: Two drug-resistant cell lines, TCC8702/A1000 (adriamycin 1000 ng/mL) and TCC8803/A200 (adriamycin 200 ng/mL), were established after long-term adriamycin treatment for at least 16 months. Their biological characteristics, including growth morphology, doubling time and cell cycle, were analysed. The drug-resistance pattern to various anticancer drugs was measured using a microplate cytotoxicity assay. The modulation of drug sensitivity by calcium-channel blockers and protein kinase C inhibitor was assessed among the different cancer cell lines. RESULTS: Both MDR sublines had lower growth rates, lower saturation densities and higher nuclear/cytoplasmic ratios than the parent cell lines. DNA staining and cell cycle analysis revealed that both TCC8702/A1000 and TCC8803/A200 cells had a decreased S-phase fraction and the TCC8803/A200 cells a changed stem line; both sublines showed increased expression of membranous glycoprotein gp-170. The cytoplasmic content of glutathione and glucose-6-phosphate dehydrogenase were not related to the MDR development in the sublines. The drug-resistance index of TCC8702/A1000 to adriamycin was 121-fold higher than the native cell line and TCC8803/A200 was 189-fold higher. TCC8803/A200 also had a broader MDR to cisplatin, vinblastine and vincristine. Calcium-channel blockers (verapamil, quinidine) and protein kinase C inhibitors (tamoxifen) inhibited gp-170 activity and slowed the drug-efflux pump, with the acquired-MDR cells subsequently accumulating anticancer drugs. A calcium antagonist-based combination of modulators all presented synergistic cytotoxic enhancement of the anticancer drugs. Parent TCC cell lines had a poorer response to modulator treatment than their MDR sublines. CONCLUSION: Different MDR mechanisms and subsequent modulator responses exist between native and acquired drug resistance in TCC cells. Acquired MDR seems strongly related to increased gp-170 expression and responds well to calcium antagonists. This phenomenon may be applicable in clinical conditions.

Monoclonal antibodies against renal tumors: the potential application in discrimination of ambiguous adenocarcinoma or transitional cell carcinoma of kidney.

PURPOSE: We tested the discrimination ability of 2 monoclonal antibodies, mAB 90 and 2-2, in renal carcinomas, including renal cell carcinoma and transitional cell carcinoma of the kidney. MATERIALS AND METHODS: Two monoclonal antibodies raised in renal adenocarcinoma (mAB 90, IgG3 subclass and mAB 2-2, IgG1 subclass), have been generated in our laboratory by hybridoma technique. The tumor associated antigens recognized by these IgG subclass monoclonal antibodies are located in the cell membrane of tumor cells. Antibodies were purified from mice ascites through protein A-Sepharose 4B affinity column and then conjugated with fluorescein isothiocyanate fluorescence by dimethyl sulfoxide method. The binding activity of these antibodies was measured by direct immunofluorescence method and analyzed in a flow cytometer. Forty-five cases of renal cell carcinoma and 16 cases of transitional cell carcinoma of the renal pelvis were collected, and the recognition power of these 2 antibodies was tested. Frozen tumor tissues were prepared and allocated into single cell suspensions in phosphate buffered saline before adding diluted (1:10) conjugated antibodies. Irrelevant antibody and negative tumor cell lines without any reaction with these antibodies were used as background fluorescence control. RESULTS: Reactivities of mAB 90 and mAB 2-2 for renal cell carcinoma tissues were 80 and 91%, respectively. On the contrary the reactivities of mAB 90 and mAB 2-2 for transitional cell carcinoma of renal pelvis tissues were 0 and 69%, respectively. mAB 90 (+)/mAB 2-2 (-) expression pattern had 76% accurate diagnostic rate for renal cell carcinoma and mAB 90 (+)/mAB 2-2 (+) pattern had 69% accurate diagnostic rate for transitional cell carcinoma of the kidney. CONCLUSIONS: When facing pathologically ambiguous kidney tumors, the binding specificity of mAB 90 and mAB 2-2 may be useful for discrimination between renal cell carcinoma tumors and transitional cell carcinoma of the renal pelvis.

The correlation of membranous glycoprotein-gp-170, cytoplasmic glutathione and glucose-6-phosphate dehydrogenase levels with multidrug resistance in transitional cell carcinoma cell lines of the urinary tract.

The expression of membranous glycoprotein gp-170, cytoplasmic glutathione (GSH) and energy-related glucose-6-phosphate dehydrogenase (G-6-PD) in cultured normal urothelial cells and transitional cell carcinoma (TCC) cell lines was analyzed by flow cytometric and enzymatic methods. The chemosensitivity of these tumor cells to four major types of anticancer drugs, including cisplatin, thiotepa, methotrexate, 5-fluorouracil, adriamycin and vinblastine, was correlated with biological activities in TCC cell lines. The TCC cell lines displayed a general sensitivity to anticancer drugs with a low incidence of highly resistant cell lines (23%). The expression of multidrug resistance was not related to cellular differentiation or invasiveness of cancer cells. Only 24% of TCC cell lines had an elevated expression of gp-170, but their expression was not related to drug resistance. Increased cytoplasmic GSH and G-6-PD was observed in over 90 per cent of TCC cell lines, but no correlation with drug resistance and cellular differentiation was observed. The biological activities of GSH and G-6-PD were not related to the drug resistance of TCC. The low expression rate of gp-170 in TCC cells indicates that other mechanisms should be involved in the development of MDR in TCC cells.

Epidermoid cysts of the testis: diagnosis by ultrasonography and magnetic resonance imaging resulting in organ-preserving surgery.

OBJECTIVE: To present experience in the diagnosis and management of patients with an epidermoid cyst of the testes and to confirm the role of conservative surgery. PATIENTS AND METHODS: The records from the last 26.5 years of patients diagnosed as having a testicular tumour were reviewed retrospectively. Those patients with a confirmed epidermoid cyst were evaluated for age, clinical assessment, methods of diagnosis, treatment and follow-up. RESULTS: Amongst a total of 131 testicular tumours, 11 patients (8.4%; mean age 25.7 years, range 21-35) were diagnosed pathologically as having an epidermoid cyst. Pre-operative suspicion of the benign nature of the lesions was supported by testicular ultrasonography in six patients and supplemented with magnetic resonance imaging (MRI) in one. An operation sparing the testicles was performed in eight patients after the diagnosis of epidermoid cyst was confirmed from frozen sections. Three patients were treated by radical orchidectomy. There were no relapses after a median follow-up of 47.3 months (range 2-82). CONCLUSION: In this series, the relative incidence of epidermoid cyst was higher than that reported in the literature (1-2%). Ultrasonography and MRI of the testes may allow the diagnosis to be made preoperatively. The absence of relapse in these patients further supports the use of organ-sparing surgery in these young men.

The guanylyl cyclase-A receptor transduces an atrial natriuretic peptide/ATP activation signal in the absence of other proteins.

Attempts to activate partially purified preparations of the guanylyl cyclase-A (GC-A) receptor with atrial natriuretic peptide (ANP) have previously failed, leading to speculation that essential cofactors are lost during purification procedures. The receptor was modified to contain the FLAG epitope (DYKDDDDK), expressed in Sf9 cells, and purified to apparent homogeneity (4.3 mumol cyclic GMP formed/min/mg protein; 5.8 mmol 125I-ANP binding site/mg protein) by a combination of immunoaffinity, Q-Sepharose FF, and wheat germ agglutinin batch chromatography. High initial protein/detergent ratios, the presence of glycerol (40%), and the inclusion of protein phosphatase inhibitors in all buffers resulted in the purification of a receptor that continued to transduce the ANP/ATP activation signal. Both native and purified GC-A contained a single class of high affinity ANP binding sites (Kd = 60 pM) and an equivalent EC50 for ATP (0.3 mM). Positive cooperativity as a function of MnGTP was retained during purification. Thus, GC-A is capable of transducing a ligand binding signal in the absence of other proteins.