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12578 citation(s) found for "Ma, John".

Surgical Anatomy Of Dural Defects In Spontaneous Spinal Cerebrospinal Fluid Leaks
Cohen‐Gadol, Aaron , Mokri, Bahram, Piepgras, David G., Meyer, Fredric B. , Atkinson, John L. D.

Operative Neurosurgery | April 3, 2006 | Volume: 58 | Issue: suppl_4 | Pages: ONS-238-ONS-245

10.1227/01.neu.0000204712.16099.fb | PMID 16582646 Get It

Abstract Objective: Spontaneous intracranial hypotension is typically caused by a spontaneous spinal cerebrospinal fluid (CSF) leak. The configuration of the related dural defects can be complex. We describe our experience with the surgical anatomy of these defects. Methods: Thirteen consecutive patients with spontaneous spinal CSF leaks who underwent surgical exploration at Mayo Clinic between 1994 and 2003 were studied. All patients' records, imaging studies, detailed intraoperative findings, and outcomes were reviewed. Results: There were four men and nine women with an average age of 40 years (range, 12–62 yr). Preoperative imaging studies revealed a single site of CSF leak in eight patients, two sites in three patients, and multiple sites in two patients. Intraoperatively, the exact site of leakage could not be found in four patients. Among the other nine patients, primary closure of a meningeal diverticulum was achieved in one patient. Significant regional attenuation of the dura prevented primary repair of the leak site in eight patients. Muscle, fibrin glue, and Gelfoam (Upjohn Co., Kalamazoo, MI) soaked in patient's own blood were commonly used to pack the epidural space in an attempt to seal the site of the leak. Ligation of two nonappendicular nerve roots allowed closure of the leak in one of these patients. Postoperatively, resolution of symptoms occurred in eight patients, significant improvement was noted in three patients, and only transient resolution in two. The mean duration of follow-up was 20.5 months. Conclusion: Surgery for closure of spontaneous spinal CSF leaks may not be straightforward. Even when extradural CSF leakage is discovered preoperatively by imaging studies, it may not always be possible to identify the exact site of the leakage intraoperatively. Furthermore, the anatomy of the dural defects may be complex and not amenable to primary closure. In such cases, the use of adjuvant techniques during surgical exploration may be effective.
Three-Dimensional Structure of the Water-Insoluble Protein Crambin in Dodecylphosphocholine Micelles and Its Minimal Solvent-Exposed Surface
Ahn, Hee‐Chul , Juranić, Nenad, Macura, Slobodan , Markley, John L.

Journal of the American Chemical Society | March 29, 2006 | Volume: 128 | Issue: 13 | Pages: 4398-4404

10.1021/ja057773d | PMID 16569017 Get It

PDLIM4 repression by hypermethylation as a potential biomarker for prostate cancer.
Vanaja, Donkena Krishna, Morlan, Bruce W., Cheville, John C. , Neumann, Roxann M., Lieber, Michael M., Tindall, Donald J., Ballman, Karla V. , Young, Charles Y.F.

Clinical Cancer Research | March 21, 2006 | Volume: 12 | Issue: 4 | Pages: 1128-1136

10.1158/1078-0432.ccr-05-2072 | PMID 16489065 Get It

Abstract PURPOSE: We analyzed the expression of genes to identify reliable molecular markers in the diagnosis and progression of prostate cancer. EXPERIMENTAL DESIGN: Gene expression profiling was done using HG-U133 set microarrays in 32 prostate cancer and 8 benign tissues of patients with cancer. Expression levels of 11 genes were selected for quantitative real-time PCR evaluation in 52 prostate cancer and 20 benign tissues. Further, to assess transcriptional inactivation, we analyzed the promoter methylation of genes by quantitative methylation-specific PCR in 62 tumor and 36 benign tissues. RESULTS: Our results showed a significant down-regulation in the mRNA expression levels of PRIMA1, TU3A, PDLIM4, FLJ14084, SVIL, SORBS1, C21orf63, and KIAA1210 and up-regulation of FABP5, SOX4, and MLP in prostate cancer tissues by TaqMan real-time PCR. Quantitative methylation-specific PCR of PDLIM4, SVIL, PRIMA1, GSTP1, and PTGS2 detected prostate carcinoma with a sensitivity of 94.7%, 75.4%, 47.4%, 89.5%, and 87.7%, and a specificity of 90.5%, 75%, 54.2%, 95.8%, and 90.2%, respectively. Using this panel of methylation markers in combination, we were able to distinguish between prostate cancer and adjacent benign tissues with sensitivities and specificities of about 90% to 100%. Our data provide evidence of transcriptional repression of the putative tumor suppressor gene PDLIM4 by hypermethylation. CONCLUSIONS: Our analysis revealed differential expression of eight down-regulated and three up-regulated genes, implicating their role in prostate cancer development and progression. We further showed that the hypermethylation of PDLIM4 gene could be used as a sensitive molecular tool in detection of prostate tumorigenesis.
Phase I Evaluation of Oral and Intravenous Vinorelbine in Pediatric Cancer Patients: A Report from the Children's Oncology Group
Johansen, Mary , Kuttesch, John F., Bleyer, W. Archie, Krailo, Mark , Ames, Matthew M. , Madden, Timothy

Clinical Cancer Research | March 21, 2006 | Volume: 12 | Issue: 2 | Pages: 516-522

10.1158/1078-0432.ccr-05-1541 | PMID 16428494 Get It

Abstract Purpose: Vinorelbine (Navelbine) is an orally absorbable Vinca with broad antitumor activity. It differs from other Vinca in that it is structurally modified on the catharanthine nucleus and has differential actions on tubulin that render it less neurotoxic than other compounds in this class. We conducted a phase I study of vinorelbine given the activity of Vinca alkaloids in many pediatric tumors. Experimental Design: We evaluated the safety and pharmacokinetics of oral and i.v. vinorelbine administered weekly × 6 in children (age, 2-17 years) with different tumors. Patients with disease involvement in the bone marrow were eligible but were stratified and dose-escalated separately. Oral vinorelbine (week 1) was administered as liquid-filled gelatin capsules at thrice the i.v. dose. Intravenous vinorelbine doses of 24 to 37.5 mg/m2 were administered on weeks 2 to 6. Results: The dose-limiting toxicity in patients without marrow involvement was reversible neutropenia. Common nonhematologic toxicities included ≤ grade 2 nausea/vomiting and increased hepatic transaminases. A higher mean i.v. ClTB was observed (1.75 ± 1.0 L/h/kg) compared with adult reports, with a mean t1/2B of 16.5 ± 9.7 hours. Mean oral bioavailability was 28.5 ± 22.5%. The apparent oral clearance (12.1 ± 13.0 L/h/kg) and volume of distribution (69.4 ± 30.6 L/kg) were substantially higher than in adults given similar oral doses. Conclusions: The maximum tolerated dose in children without bone marrow involvement was 30 mg/m2, similar to that reported in adults, with myelosuppression being the dose-limiting toxicity. Higher plasma clearance resulted in lower area under the plasma concentration-time curves at a given dose compared with that reported in adults.
Phase I and Pharmacokinetic Study of Flavopiridol followed by 1-β-d-Arabinofuranosylcytosine and Mitoxantrone in Relapsed and Refractory Adult Acute Leukemias
Karp, Judith E. , Passaniti, Antonino , Gojo, Ivana , Kaufmann, Scott H. , Bible, Keith C. , Garimella, Τushar , Greer, Jacqueline M., Briel, Janet, Gore, Steven D. , Tidwell, Michael L., Ross, Douglas D., Wright, John J., Bauer, Kenneth S., Smith, B. Douglas , Wright, John J., Colevas, Alexander Dimitrios , Kaufmann, Scott H

Clinical Cancer Research | March 21, 2006 | Volume: 11 | Issue: 23 | Pages: 8403-8412

10.1158/1078-0432.ccr-05-1201 | PMID 16322302 Get It

Abstract Purpose: The serine/threonine kinase inhibitor flavopiridol targets multiple cyclin-dependent kinases, induces checkpoint arrest, and interrupts transcriptional elongation. We designed a phase I clinical trial using a timed sequential therapy approach where flavopiridol was given for the dual purpose of initial cytoreduction and enhancing cell cycle progression of the remaining leukemia cell cohort followed by cycle-dependent drugs 1-β-d-arabinofuranosylcytosine (ara-C) and mitoxantrone. Experimental Design: Flavopiridol was given by 1-hour infusion daily for 3 days beginning day 1 followed by 2 g/m2/72 h ara-C beginning day 6 and 40 mg/m2 mitoxantrone beginning day 9. In vivo correlates included pharmacokinetics, modulation of blast cycle regulators, and serum and marrow supernatant vascular endothelial growth factor levels. Results: Of 34 adults receiving induction therapy, 16 (47%) evinced direct leukemia cytotoxicity with ≥50% drop in peripheral blast counts and tumor lysis in 9 (26%). Four (12%) died during therapy (two fungal infections and two sudden death). Dose-limiting toxicity occurred at 60 mg/m2/d with profound neutropenia >40 days duration, and maximal tolerated dose was 50 mg/m2/d. Overall response rate was 31% in 26 acute myelogenous leukemia and 12.5% in acute lymphoblastic leukemia. Pharmacokinetics showed that a linear two-compartment model with first-order elimination provided the best fit of the observed concentration versus time data. Flavopiridol down-regulated one or more target proteins in marrow blasts in vivo. Vascular endothelial growth factor was detected in sera and marrow supernatant pretreatment, and sera obtained on day 3 inhibited bovine aortic endothelial cell proliferation by a mean of 32% (range, 10-80%). Conclusions: Our data suggest that flavopiridol is cytotoxic to leukemic cells and, when followed by ara-C and mitoxantrone, exerts biological and clinical effects in patients with relapsed and refractory acute leukemias. These findings warrant continuing development of flavopiridol at 50 mg/m2/d × 3 days in combination with cytotoxic and biological agents for acute leukemias.
Baseline Factors as Predictors of Clinical Progression of Benign Prostatic Hyperplasia in Men Treated With Placebo
Crawford, E. David , Wilson, Shandra, McConnell, John D., Slawin, Kevin M., Lieber, Michael C., Smith, Joseph A. , Meehan, Alan G., Bautista, Oliver, Noble, William R., Kusek, John W., Nyberg, Leroy M., Roehrborn, Claus G.

Journal of Urology | March 3, 2006 | Volume: 175 | Issue: 4 | Pages: 1422-1427

10.1016/s0022-5347(05)00708-1 | PMID 16516013 Get It

Fulvestrant in Women With Advanced Breast Cancer After Progression on Prior Aromatase Inhibitor Therapy: North Central Cancer Treatment Group Trial N0032
Rowland, Kendrith M. , Mirchandani, D., Bernath, Albert M., Camoriano, John , Fishkin, Paul A. S., Nikcevich, Daniel A., Perez, Edith A. , Ingle, James N. , Suman, Vera J.

Journal of Clinical Oncology | February 28, 2006 | Volume: 24 | Issue: 7 | Pages: 1052-1056

10.1200/jco.2005.04.1053 | PMID 16505423 Get It

PurposeFulvestrant is an antiestrogen that leads to estrogen receptor degradation and has demonstrated efficacy in breast cancer patients who have had disease recurrence or progression after tamoxifen. This study was designed to examine the efficacy and toxicity of fulvestrant in patients with disease progression on a third-generation aromatase inhibitor (AI).Patients and MethodsA one-stage phase II trial was conducted in postmenopausal women with measurable disease by Response Evaluation Criteria in Solid Tumors criteria who experienced disease progression after treatment with a third-generation AI and, at most, one additional hormonal agent. Tumors must have been estrogen receptor and/or progesterone receptor positive. The primary end point was objective response rate, and secondary end points were time to disease progression, survival, duration of response, and toxicity.ResultsEighty patients were enrolled, and three were ineligible. Characteristics of the 77 eligible patients included median age of 68 years, performance score of 0 or 1 in 91% of patients, visceral dominant disease in 88% of patients, two prior hormonal treatments in 73% of patients, and prior chemotherapy for metastatic disease in 32% of patients. Eleven patients (14.3%) achieved a partial response, and 16 patients (20.8%) had stable disease for at least 6 months, for a clinical benefit rate of 35%. Antitumor activity seemed to be higher in women with prior treatment with AI alone compared with women whose prior treatment also included tamoxifen. Median time to progression was 3 months, and median survival time was 20.2 months. Fulvestrant was well tolerated.ConclusionFulvestrant is a well-tolerated treatment and has efficacy against breast cancers that have progressed after therapy with a third-generation AI.
Phase III Comparison of Depomedroxyprogesterone Acetate to Venlafaxine for Managing Hot Flashes: North Central Cancer Treatment Group Trial N99C7
Loprinzi, Charles L. , Levitt, Ralph, Barton, Debra L. , Sloan, Jeff A. , Dakhil, Shaker R. , Nikcevich, Daniel A., Bearden, James D. , Mailliard, James A., Tschetter, Loren K., Fitch, Tom R., Kugler, John W.

Journal of Clinical Oncology | February 27, 2006 | Volume: 24 | Issue: 9 | Pages: 1409-1414

10.1200/jco.2005.04.7324 | PMID 16505409 Get It

Purpose Vasomotor hot flashes are a common problem in menopausal women. Given concerns regarding estrogen and/or combined hormonal therapy, other treatment options are desired. Prior trials have confirmed that progestational agents and newer antidepressants effectively reduce hot flashes. This current trial compared a single intramuscular dose of medroxyprogesterone acetate (MPA), depot preparation, versus daily oral venlafaxine as treatment for hot flashes. Methods Women with bothersome hot flashes were entered onto this trial, were randomly assigned to treatment, and then had a baseline week where hot flash scores were recorded without treatment. They were then treated and observed for 6 weeks; daily diaries were used to measure hot flash frequencies and severities. There were 109 patients per each arm randomly assigned to receive MPA 400 mg intramuscularly for a single dose versus venlafaxine 37.5 mg per day for a week, then 75 mg per day. Results During the sixth week after random assignment, hot flash scores were reduced by 55% in the venlafaxine arm versus 79% in the MPA arm (P < .0001). In an intention-to-treat analysis, 46% of venlafaxine patients (50 of 109) compared with 74% of the MPA patients (81 of 109) had a decrease in hot flashes by more than 50% from baseline (P < .0001). Less toxicity was reported in the MPA arm. Conclusion A single MPA dose seems to be well tolerated and more effectively reduces hot flashes than does venlafaxine.
Imaging of the Pineal Region and Spine: Self-Assessment Module
Roberts, Catherine C. , Banks, Kevin , Hesselink, John R. , Chew, Felix S.

American Journal of Roentgenology | February 24, 2006 | Volume: 186 | Issue: 3_supplement | Pages: S224-S226

10.2214/ajr.05.2231 | PMID 16498138 Get It

Lymphocyte Activation Antigen CD70 Expressed by Renal Cell Carcinoma Is a Potential Therapeutic Target for Anti-CD70 Antibody-Drug Conjugates
Gordon, Kristine A., Toki, Brian E., Yamane, Andrew K., Hering, Michelle A., Cerveny, Charles G., Petroziello, Joseph M., Ryan, Maureen C. , Smith, Leia M., Simon, Ronald , Sauter, Guido , Oflazoglu, Ezogelin, Doronina, Svetlana O., Meyer, Damon L., Francisco, Joseph A., Senter, Peter D. , Copland, John A. , Wood, Christopher G. , Wahl, Alan F., Law, Che‐Leung , Carter, Paul

Cancer Research | February 17, 2006 | Volume: 66 | Issue: 4 | Pages: 2328-2337

10.1158/0008-5472.can-05-2883 | PMID 16489038 Get It

AbstractMetastatic renal cell carcinoma (RCC) is an aggressive disease refractory to most existing therapeutic modalities. Identifying new markers for disease progression and drug targets for RCC will benefit this unmet medical need. We report a subset of clear cell and papillary cell RCC aberrantly expressing the lymphocyte activation marker CD70, a member of the tumor necrosis factor superfamily. Importantly, CD70 expression was found to be maintained at the metastatic sites of RCC. Anti-CD70 antibody-drug conjugates (ADC) consisting of auristatin phenylalanine phenylenediamine (AFP) or monomethyl auristatin phenylalanine (MMAF), two novel derivatives of the anti-tubulin agent auristatin, mediated potent antigen-dependent cytotoxicity in CD70-expressing RCC cells. Cytotoxic activity of these anti-CD70 ADCs was associated with their internalization and subcellular trafficking through the endosomal-lysosomal pathway, disruption of cellular microtubule network, and G2-M phase cell cycle arrest. The efficiency of drug delivery using anti-CD70 as vehicle was illustrated by the much enhanced cytotoxicity of antibody-conjugated MMAF compared with free MMAF. Hence, ADCs targeted to CD70 can selectively recognize RCC, internalize, and reach the appropriate subcellular compartment(s) for drug release and tumor cell killing. In vitro cytotoxicity of these ADCs was confirmed in xenograft models using RCC cell lines. Our findings provide evidence that CD70 is an attractive target for antibody-based therapeutics against metastatic RCC and suggest that anti-CD70 ADCs can provide a new treatment approach for advanced RCC patients who currently have no chemotherapeutic options. (Cancer Res 2006; 66(4): 2328-37)