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12583 citation(s) found for "Vu, John A".

Accuracy of Colorectal Polyp Self-Reports: Findings from the Colon Cancer Family Registry
Madlensky, Lisa , Daftary, Darshana, Burnett, Terrilea, Harmon, Patricia, Jenkins, Mark A. , Maskiell, Judi, Nigon, Sandra, Phillips, Kerry, Templeton, Allyson , Haile, Robert W. , Potter, John D. , Gallinger, Steven, Limburg, Paul J. , Baron, John A. , Jenkins, Mark A , Haile, Robert W , Potter, John D

Cancer Epidemiology, Biomarkers & Prevention | September 13, 2007 | Volume: 16 | Issue: 9 | Pages: 1898-1901

10.1158/1055-9965.epi-07-0151 | PMID 17726139 Get It

Abstract Introduction: Colorectal adenomas and other types of polyps are commonly used as end points or risk factors in epidemiologic studies. However, it is not known how accurately patients are able to self-report the presence or absence of adenomas following colonoscopy. Methods: Participants in the Colon Cancer Family Registry provided self-reports of recent colorectal cancer (CRC) screening activity, and whether or not they had ever been told they had a polyp. Positive and negative predictive values for polyp self-report were calculated by comparing medical records with self-reports from 488 participants. Results: The positive predictive value for self-reported polyp was 80.9%, and the negative predictive value was 85.8%. The predictive values did not differ by age group or sex, but participants with a previous diagnosis of CRC had a lower negative predictive value (76.2%) than participants with no personal history of CRC (89.0%; P = 0.04). Conclusions: Predictive values for self-reports of polyps are fairly high, but researchers needing accurate polyp data should obtain medical record confirmation. Pursuing medical records on only those participants self-reporting a polyp could result in an underestimation of the polyp prevalence in a study population. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1898–901)
Low Dose Nesiritide and the Preservation of Renal Function in Patients With Renal Dysfunction Undergoing Cardiopulmonary-Bypass Surgery
Chen, Horng H. , Sundt, Thoralf M. , Cook, David J. , Heublein, Denise M., Burnett, John C.

Circulation | September 10, 2007 | Volume: 116 | Issue: 11_supplement | Pages: No page available

10.1161/circulationaha.106.697250 | PMID 17846293 Get It

Background— Renal insufficiency is associated with increased morbidity and mortality after cardiopulmonary bypass cardiac surgery. B-type natriuretic peptide is a cardiac hormone that enhances glomerular filtration rate and inhibits aldosterone. Cystatin has been shown to be a better endogenous marker of renal function than creatinine. Methods and Results— We performed a double-blinded placebo-controlled proof of concept pilot study in patients (n=40) with renal insufficiency preoperatively (defined as an estimated creatinine clearance of <60 mL/min determined by the Cockroft-Gault formula), undergoing cardiopulmonary bypass cardiac surgery. Patients were randomized to placebo (n=20) or IV low dose nesiritide (n=20; 0.005 μg/Kg/min) for 24 hours started after the induction of anesthesia and before cardiopulmonary bypass. Patients in the nesiritide group had an increase of plasma B-type natriuretic peptide and its second messenger cGMP with a decrease in plasma cystatin levels at the end of the 24-hour infusion. These changes were not observed in the placebo group. There was a significant activation of aldosterone in the placebo group at the end of the 24-hour infusion, but not in the nesiritide group. At 48 and 72 hours, there was a decrease in estimated creatinine clearance and an increase in plasma cystatin as compared with end of the 24-hour infusion in the placebo group. In contrast, renal function was preserved in the nesiritide group with no significant change in estimated creatinine clearance and a trend for plasma cystatin to increase as compared with end of the 24-hour infusion. Conclusion— This proof of concept pilot study supports the conclusion that perioperative administration of low dose nesiritide is biologically active and decreases plasma cystatin in patients with renal insufficiency undergoing cardiopulmonary bypass cardiac surgery. Further studies are warranted to determine whether these physiological observations can be translated into improved clinical outcomes.
A prospective study of G-CSF–primed bone marrow as a stem-cell source for allogeneic bone marrow transplantation in children: a Pediatric Blood and Marrow Transplant Consortium (PBMTC) study
Frangoul, Haydar , Nemecek, Eneida R. , Billheimer, Dean , Khan, Shakila P. , Woolfrey, Ann E. , Manes, Becky, Cole, Catherine , Ravindranath, Yaddanapudi , Levine, John E. , Pulsipher, Michael A. , Walters, Mark C. , Ayas, Mouhab Fakhreddine , Grupp, Stephan A. , Levine, John E

Blood | September 8, 2007 | Volume: 110 | Issue: 13 | Pages: 4584-4587

10.1182/blood-2007-07-101071 | PMID 17827386 Get It

A prospective multicenter trial was conducted to evaluate the safety and feasibility of granulocyte colony-stimulating factor (G-CSF)–primed bone marrow (G-BM) in children receiving allogeneic bone marrow transplantation (BMT). A total of 42 children with a median age of 9.8 years (range, 0.8-17 years) were enrolled. Donors with median age of 9.2 years (range, 1.1-22 years) received 5 μg/kg per day of subcutaneous G-CSF for 5 consecutive days. BM was harvested on the fifth day. No donor experienced complications related to G-CSF administration or marrow har-vest. Median nucleated (NC) and CD34 cells infused was 6.7 × 108/kg (range, 2.4-18.5 × 108/kg) and 7.4 × 106/kg (range, 2-27.6 × 106/kg), respectively. Neutrophil and platelet engraftment was at a median of 19 days (range, 13-28 days) and 20 days (range, 9-44 days), respectively. A total of 13 (32%) patients developed grade 2 graft-versus-host disease (GVHD), and 5 (13%) of 40 evaluable patients developed chronic GVHD (3 limited and 2 extensive). Higher cell dose was not associated with increased risk of acute or chronic GVHD. Overall survival and event-free survival at 2 years were 81% and 69%, respectively. Collection of G-BM from pediatric donors is safe, and can result in high NC and CD34 cell doses that facilitate engraftment after myeloablative BMT without a discernable increase in the risk of GVHD.
End-of-procedure cefazolin concentrations after administration for prevention of surgical-site infection
Koopman, Erin, Erstad, Brian L. , Demeure, Michael J. , Hayes, Melinda M., Ruth, John T., Matthias, Kathryn R., Koopman, Erin M, Nix, David E.

American Journal of Health-System Pharmacy | September 5, 2007 | Volume: 64 | Issue: 18 | Pages: 1927-1934

10.2146/ajhp070047 | PMID 17823104 Get It

Neurology ® podcasts
Noseworthy, John H., Burns, Ted M.

Neurology | September 4, 2007 | Volume: 69 | Issue: 10 | Pages: 948-948

10.1212/01.wnl.0000281541.78240.9e Get It

Transoral Laser Microsurgery for Untreated Glottic Carcinoma
Grant, David G., Salassa, John R., Hinni, Michael L., Pearson, Bruce W. , Hayden, Richard E. , Perry, William C.

Otolaryngology–Head and Neck Surgery | August 31, 2007 | Volume: 137 | Issue: 3 | Pages: 482-486

10.1016/j.otohns.2007.05.064 | PMID 17765780 Get It

OBJECTIVESTo report the oncology and functional outcomes of transoral laser microsurgery (TLM) for untreated glottic carcinoma.STUDY DESIGNA 2 center prospective case series analysis.SETTINGAcademic, tertiary referral centers.RESULTSSeventy‐six patients underwent TLM. Pathologic T stages were: T1, 45 (59%); T2, 21 (28%); T3, 5 (7%); and T4, 5 (7%). Five (7%) patients had neck dissections. Five (7%) patients received adjuvant radiotherapy. Mean follow‐up was 42 months. Respective T1 and T2 5‐year Kaplan‐Meier estimates were: local control, 90% and 93%; loco‐regional control, 90% and 93%; disease specific survival, 90% and 93%; and overall survival, 94% and 93%. The average hospital stay was 2 days. Two (3%) patients experienced major complications. The overall laryngeal preservation rate was 95% (72 of 76).CONCLUSIONSTLM is a safe and effective treatment in select carcinoma of the glottic larynx. Low morbidity and mortality and short periods of hospitalization make TLM an attractive therapeutic option.SIGNIFICANCETLM is an emerging strategy in the treatment of laryngeal cancer.
Secreted Frizzled-Related Protein 1 Loss Contributes to Tumor Phenotype of Clear Cell Renal Cell Carcinoma
Zou, Hongzhi , Kreinest, Pamela, Childs, April C., Belmonte, Leandra S., LeGrand, Shauna N., Wu, Kevin J. , Luxon, Bruce A. , Sinha, Mala, Parker, Alexander S. , Sun, L-Z, Ahlquist, David A. , Wood, Christopher G. , Copland, John A. , Gumz, Michelle L.

Clinical Cancer Research | August 15, 2007 | Volume: 13 | Issue: 16 | Pages: 4740-4749

10.1158/1078-0432.ccr-07-0143 | PMID 17699851 Get It

Abstract Purpose: Incidence and mortality rates for renal cell carcinoma (RCC) have been rising for decades. Unfortunately, the molecular events that support RCC carcinogenesis remain poorly understood. In an effort to gain a better understanding of signaling events in clear cell RCC (cRCC), we investigated the antitumor activity of secreted frizzled-related protein 1 (sFRP1), a negative regulator of Wnt signaling. Experimental Design: Genomic profiling of cRCC tumors and patient-matched normal tissues was done and confirmed using quantitative PCR and immunohistochemistry. Methylation-specific PCR was done on patient samples to evaluate the mechanism responsible for sFRP1 loss. sFRP1 expression was restored in cRCC cells and the effects on tumor phenotype were characterized. Results: Genomic profiling, quantitative PCR, and immunohistochemistry indicated that loss of sFRP1 occurred in cRCC and papillary RCC patient tissues. Twelve Wnt-regulated genes were up-regulated in cRCC tissues, including c-myc and cyclin D1, potentiators of cell proliferation and survival. Methylation of the sFRP1 gene was one mechanism identified for attenuation of sFRP1 mRNA. Stable reexpression of sFRP1 in cRCC cells resulted in decreased expression of Wnt target genes, decreased growth in cell culture, inhibition of anchorage-independent growth, and decreased tumor growth in athymic nude mice. Conclusions: To our knowledge, this is the first report to show that stable restoration of sFRP1 expression in cRCC cells attenuates the cRCC tumor phenotype. Our data support a role for sFRP1 as a tumor suppressor in cRCC and that perhaps loss of sFRP1 is an early, aberrant molecular event in renal cell carcinogenesis.
Application of 188Rhenium as an Alternative Radionuclide for Treatment of Prostate Cancer after Tumor-Specific Sodium Iodide Symporter Gene Expression
Willhauck, Michael J., Samani, Bibi-Rana Sharif, Gildehaus, Franz‐Josef, Senekowitsch–Schmidtke, Reingard, Stark, Hans‐Jürgen, Göke, Burkhard, Spitzweg, Christine , Samani, Bibi Rana Sharif, Wolf, Ingo , Morris, John C.

The Journal of Clinical Endocrinology & Metabolism | August 15, 2007 | Volume: 92 | Issue: 11 | Pages: 4451-4458

10.1210/jc.2007-0402 | PMID 17698909 Get It

Abstract Context: We reported recently the induction of iodide accumulation in prostate cancer cells (LNCaP) by prostate-specific antigen promoter-directed sodium iodide symporter (NIS) expression that allowed a significant therapeutic effect of 131iodine (131I). These data demonstrated the potential of the NIS gene as a novel therapeutic gene, although in some extrathyroidal tumors, therapeutic efficacy may be limited by rapid iodide efflux due to a lack of iodide organification. Objective: In the current study, we therefore studied the potential of 188rhenium (188Re), as an alternative radionuclide, also transported by NIS, with a shorter half-life and higher energy β-particles than 131I. Results: NIS-transfected LNCaP cells (NP-1) concentrated 8% of the total applied activity of 188Re as compared with 16% of 125I, which was sufficient for a therapeutic effect in an in vitro clonogenic assay. γ-Camera imaging of NP-1 cell xenografts in nude mice revealed accumulation of 8–16% injected dose (ID)/g 188Re (biological half-life 12.9 h), which resulted in a 4.7-fold increased tumor absorbed dose (450 mGy/MBq) for 188Re as compared with 131I. After application of 55.5 MBq 131I or 188Re, smaller tumors showed a similar average volume reduction of 86%, whereas in larger tumors volume reduction was significantly increased from 73% after 131I treatment to 85% after application of 188Re. Conclusion: Although in smaller prostate cancer xenografts both radionuclides seemed to be equally effective after prostate-specific antigen promoter-mediated NIS gene delivery, a superior therapeutic effect has been demonstrated for 188Re in larger tumors.
Cell Biology of Pathologic Renal Calcification: Contribution of Crystal Transcytosis, Cell-Mediated Calcification, and Nanoparticles
Farell, Gerard, Yu, Shihui , Harrington, Sean C., Fitzpatrick, Lorraine A. , Rzewuska, Ewa, Miller, Virginia M. , Kumar, Vivek , Lieske, John C.

Journal of Investigative Medicine | August 13, 2007 | Volume: 54 | Issue: 7 | Pages: 412-424

10.2310/6650.2006.06021 | PMID 17169263 Get It

Introduction The earliest lesion in the kidneys of idiopathic calcium oxalate stone formers is deposition of calcium phosphate in the interstitium, termed a Randall's plaque. Yet the cellular and molecular factors leading to their formation are unknown. Methods The influence of urinary proteins on adhesion of preformed calcium oxalate crystals to rat continuous inner medullary collecting duct (cIMCD) cells was studied in vitro, and cIMCD cells were also exposed to calcifying media containing β-glycerophosphate for up to 28 days. Renal tissue was obtained from a stone-forming and non-stone-forming individual at the time of nephrectomy. These nanoparticles, isolated from renal stones obtained at the time of surgical resection, were analyzed and propagated in standard cell culture medium. Results Urinary proteins influence crystal adhesion to renal epithelial cells, and this activity is abnormal in the urine of stone-forming patients. cIMCD cells assumed an osteoblastic phenotype when exposed to the calcifying medium, expressing two bone matrix proteins (osteopontin and bone sialoprotein) that were also identified in the kidney of the stone-forming patient and associated with crystal deposition. Nanoparticles were propagated from the majority of renal stones. Isolates were susceptible to selected metabolic inhibitors and antibiotics and contained conserved bacterial proteins and deoxyribonucleic acid (DNA). Conclusions These results suggest new paradigms for Randall's plaque formation and idiopathic calcium oxalate stone disease. It seems unlikely that these events are driven solely by physical chemistry; rather, they are critically influenced by specific proteins and cellular responses, and understanding these events will provide clues toward novel therapeutic targets.
Search for Microbial Signatures within Human and Microbial Calcifications Using Soft X-Ray Spectromicroscopy
Benzerara, Karim , Miller, Virginia M. , Barell, Gerard, Miot, Jennyfer, Brown, Gordon E. , Kumar, Vivek , Lieske, John C.

Journal of Investigative Medicine | August 13, 2007 | Volume: 54 | Issue: 7 | Pages: 367-379

10.2310/6650.2006.06016 | PMID 17169258 Get It

Background The origin of advanced arterial and renal calcification remains poorly understood. Self-replicating, calcifying entities have been detected and isolated from calcified human tissues, including blood vessels and kidney stones, and are referred to as nanobacteria. However, the microbiologic nature of putative nanobacteria continues to be debated, in part because of the difficulty in discriminating biomineralized microbes from minerals nucleated on anything else (eg, macromolecules, cell membranes). To address this controversy, the use of techniques capable of characterizing the organic and mineral content of these self-replicated structures at the submicrometer scale would be beneficial. Methods Calcifying gram-negative bacteria ( Caulobacter crescentus, Ramlibacter tataouinensis) used as references and self-replicating calcified nanoparticles cultured from human samples of calcified aneurysms were examined using a scanning transmission x-ray microscope (STXM) at the Advanced Light Source at Lawrence Berkeley National Laboratory. This microscope uses a monochromated and focused synchrotron x-ray beam (80-2,200 eV) to yield microscopic and spectroscopic information on both organic compounds and minerals at the 25 nm scale. Results High-spatial and energy resolution near-edge x-ray absorption fine structure (NEXAFS) spectra indicative of elemental speciation acquired at the C K-edge, N K-edge, and Ca L 2,3 -edge on a single-cell scale from calcified C. crescentus and R. tataouinensis displayed unique spectral signatures different from that of nonbiologic hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 ). Further, preliminary NEXAFS measurements of calcium, carbon, and nitrogen functional groups of cultured calcified nanoparticles from humans revealed evidence of organics, likely peptides or proteins, specifically associated with hydroxyapatite minerals. Conclusion Using NEXAFS at the 25 nm spatial scale, it is possible to define a biochemical signature for cultured calcified bacteria, including proteins, polysaccharides, nucleic acids, and hydroxyapatite. These preliminary studies suggest that nanoparticles isolated from human samples share spectroscopic characteristics with calcified proteins.