Citations

Mayo Clinic

Clear

10814 citation(s) found for "Qi, Robert".

Radiosurgery for Cranial Base Chordomas and Chondrosarcomas
Foote, Robert L. , Brown, Paul D. , Pollock, Bruce E. , Link, Michael J. , Garces, Yolanda I. , Krishnan, Sunil

Neurosurgery | March 29, 2005 | Volume: 56 | Issue: 4 | Pages: 777-784

10.1227/01.neu.0000156789.10394.f5 | PMID 15792516 Get It

Abstract OBJECTIVE: To evaluate the efficacy and toxicity of radiosurgery in the treatment of cranial base chordoma and chondrosarcoma. METHODS: We reviewed 29 patients with cranial base chordoma (n = 25) or chondrosarcoma (n = 4) who underwent stereotactic radiosurgery between September 1990 and December 2002. The median patient age was 45 years (range, 10–81 yr). Nineteen patients also had radiation therapy before or in conjunction with radiosurgery (median dose, 50.4 Gy). The median tumor volume was 14.4 cm3 (range, 0.6–65.1 cm3). The median tumor margin dose was 15 Gy (range, 10–20 Gy); the median maximum radiation dose was 30 Gy (range, 20–40 Gy). Median clinical and imaging follow-up periods were 4.8 and 4.5 years, respectively. RESULTS: Seven chordoma patients (28%) had tumor progression (in-field, n = 3; out-of-field, n = 4), whereas 18 had stable disease or tumor shrinkage. No patient with a chondroid chordoma had tumor enlargement. The actuarial tumor control rates were 89 and 32% at 2 and 5 years, respectively. All 4 patients with chondrosarcoma had tumor control. Clinically, 7 patients (24%) had improvement of pretreatment symptoms, 16 (55%) remained stable, and 6 (21%) worsened. Three patients with tumor progression died. Ten patients (34%) had radiation-related complications. Complications included cranial nerve deficits (n = 6), radiation necrosis (n = 5), and pituitary dysfunction (n = 3). Patients having radiosurgery alone had no toxicity. CONCLUSION: Cranial base chordomas and chondrosarcomas remain a formidable management challenge. Radiosurgery as an adjunct to surgical resection provides in-field tumor control for some patients, but radiation-related complications are relatively high, especially when radiosurgery is combined with fractionated radiation therapy.
Monoblock and modular total shoulder arthroplasty for osteoarthritis
Mileti, Joseph, Sperling, John W. , Cofield, Robert H. , Harrington, J. R., Hoskin, Tanya L.

The Journal of Bone and Joint Surgery. British volume | March 25, 2005 | Volume: 87-B | Issue: 4 | Pages: 496-500

10.1302/0301-620x.87b4.15558 | PMID 15795199 Get It

There are theoretical and practical advantages to modular rather than monoblock designs of prostheses for shoulder arthroplasty, but there are no reported studies which specifically compare the clinical and radiological results of their use. We have compared the results of unconstrained total shoulder arthroplasty for osteoarthritis using both types of implant. The monoblock design was used between 1992 and 1995 and the modular design after 1995. Both had cemented all-polyethylene glenoids, the monoblock with matched and the modular with mismatched radii of curvature. There were 34 consecutive shoulders in each group with a mean follow-up of 6.1 years in the first and 5.2 years in the second. There were no significant differences in improvement of pain scores, active elevation, external rotation, internal rotation, patient satisfaction, or the Neer ratings between the two groups. Two of 28 glenoid components in the first group and six of 30 in the second met the criteria for being radiologically at risk for loosening (p = 0.25). There were no significant differences in clinical outcome or radiological changes between the first- and second-generation designs of implant for shoulder arthroplasty.
Diagnostic Performance of Quantitative κ and λ Free Light Chain Assays in Clinical Practice
Katzmann, Jerry A., Abraham, Roshini S. , Dispenzieri, Angela , Lust, John A., Kyle, Robert A. , Dispenzieri, Angela

Clinical Chemistry | March 18, 2005 | Volume: 51 | Issue: 5 | Pages: 878-881

10.1373/clinchem.2004.046870 | PMID 15774572 Get It

Abstract Background: The quantitative assay for free light chains (FLCs) is a recently introduced commercial test reported to be sensitive and specific for detecting FLC diseases such as primary systemic amyloidosis (AL), light chain deposition disease (LCDD), nonsecretory multiple myeloma (NSMM), and light chain multiple myeloma. We evaluated its diagnostic performance in clinical practice. Methods: All FLC clinical test results generated in 2003 were abstracted from the Laboratory Information System. Diagnoses were obtained from the Dysproteinemia database and the patient medical history. Results: In 2003, we received samples for FLC assays from 1020 Mayo Clinic patients. The majority of these patients (88%) had bone marrow-derived monoclonal plasma cell disorders (PCDs). The 121 patients who did not have monoclonal gammopathy all had FLC κ/λ ratios within the range of values obtained for a reference population in our laboratory. Among the patients with monoclonal gammopathies were patients with multiple myeloma (330), AL (269), monoclonal gammopathy of undetermined significance (114), smoldering multiple myeloma (72), plasmacytoma (22), NSMM (20), macroglobulinemia (9), LCDD (7), and a variety of other PCDs. Among the 110 AL patients who had not been previously treated and who had a FLC assay performed within 120 days of diagnosis, the FLC κ/λ ratio was positive in 91% compared with 69% for serum immunofixation electrophoresis (IFE) and 83% for urine IFE. The combination of serum IFE and serum FLC assay detected an abnormal result in 99% (109 of 110) of patients with AL. Conclusion: The performance of the FLC assay in this analysis of clinical laboratory data is consistent with results from published retrospective validation studies.
The Role of Oxygen Tension in Penile Erection and Its Relationship to Erectile Dysfunction
Moreland, Robert B. , Nehra, Ajay, Park, Jong‐Kwan

The Scientific World JOURNAL | March 16, 2005 | Volume: 4 | Issue: No issue available | Pages: 279-290

10.1100/tsw.2004.77 | PMID 29861676 Get It

The corpus cavernosum of the penis is one of the few vascular beds in which there is a change in oxygen tension with function (blood PO225-40mm Hg in the flaccid state, and 90-100mm Hg in the erect state). This change in oxygen tension exposes the components of the corpus cavernosum to a variety of cytokines, humoral, vasoactive, and growth factors which may affect the structure and function of the endothelial cells, smooth muscle cells, neurons and extracellular matrix. Among these cell types, endothelial cells are the first line of defense to blood-borne stress and can affect the underlying smooth muscle via paracrine mechanisms. Impotence is defined as the inability to obtain or sustain an erection sufficient for vaginal penetration and can result from a variety of pathological conditions, vascular disease, endocrine disease, neurological disease, and psychogenic disorders. The penis is a vascular organ and as such is susceptible to the effects of vascular diseases. This review will discuss the basic etiology of erection and vasculogenic erectile dysfunction and explore the role oxygen tension in regulating various cellular and humoral factors as well as trabecular structure and function.
Intrathecal Mafosfamide: A Preclinical Pharmacology and Phase I Trial
Blaney, Susan M. , Balis, Frank M. , Arndt, Carola A.S., Heideman, Richard L., Geyer, J. Russell, Packer, Roger J. , Adamson, Peter C. , Jaeckle, Kurt A. , Klenke, Renee, Aikin, Alberta, McCully, Cynthia Lester , Poplack, David G., Berg, Stacey L. , Murphy, Robert L.

Journal of Clinical Oncology | February 26, 2005 | Volume: 23 | Issue: 7 | Pages: 1555-1563

10.1200/jco.2005.06.053 | PMID 15735131 Get It

Purpose Preclinical studies of mafosfamide, a preactivated cyclophosphamide analog, were performed to define a tolerable and potentially active target concentration for intrathecal (IT) administration. A phase I and pharmacokinetic study of IT mafosfamide was performed to determine a dose for subsequent phase II trials. Patients and Methods In vitro cytotoxicity studies were performed in MCF-7, Molt-4, and rhabdomyosarcoma cell lines. Feasibility and pharmacokinetic studies were performed in nonhuman primates. These preclinical studies were followed by a phase I trial in patients with neoplastic meningitis. There were five dose levels ranging from 1 mg to 6.5 mg. Serial CSF samples were obtained for pharmacokinetic studies in a subset of patients with Ommaya reservoirs. Results The cytotoxic target exposure for mafosfamide was 10 μmol/L. Preclinical studies demonstrated that this concentration could be easily achieved in ventricular CSF after intraventricular dosing. In the phase I clinical trial, headache was the dose-limiting toxicity. Headache was ameliorated at 5 mg by prolonging the infusion rate to 20 minutes, but dose-limiting headache occurred at 6.5 mg dose with prolonged infusion. Ventricular CSF mafosfamide concentrations at 5 mg exceeded target cytotoxic concentrations after an intraventricular dose, but lumbar CSF concentrations 2 hours after the dose were less than 10 μmol/L. Therefore, a strategy to alternate dosing between the intralumbar and intraventricular routes was tested. Seven of 30 registrants who were assessable for response had a partial response, and six had stable disease. Conclusion The recommended phase II dose for IT mafosfamide, administered without concomitant analgesia, is 5 mg over 20 minutes.
Diagnosis and Management of Waldenstrom's Macroglobulinemia
Dimopoulos, Meletios Α. , Kyle, Robert A. , Anagnostopoulos, Athanasios K. , Treon, Steven P. , Dimopoulos, Meletios A

Journal of Clinical Oncology | February 26, 2005 | Volume: 23 | Issue: 7 | Pages: 1564-1577

10.1200/jco.2005.03.144 | PMID 15735132 Get It

Purpose To review the diagnostic criteria, prognostic factors, response criteria, and treatment options of patients with Waldenstrom's macroglobulinemia (WM). Methods A review of published reports was facilitated by the use of a MEDLINE computer search and by manual search of the Index Medicus. Results WM should be regarded as a distinct clinicopathologic entity and confined to those patients with lymphoplasmacytoid lymphoma who have demonstrable serum immunoglobulin M monoclonal protein. Treatment decisions should rely on specific clinical and laboratory criteria. Initiation of therapy should not be based on serum monoclonal protein levels per se. The three main choices for systemic primary treatment of symptomatic patients with WM include alkylating agents (chlorambucil), nucleoside analogs (fludarabine and cladribine), and the monoclonal antibody rituximab. There are no data from prospective randomized studies to recommend the use of one first-line agent over another, although consideration of a patient's candidacy for autologous stem-cell transplantation (ASCT) should be taken into account to avoid stem cell–damaging agents. There are preliminary data to suggest that combinations of nucleoside analogs and alkylating agents with or without rituximab may improve response rates at the expense of higher toxicity. Conclusion WM is a distinct low-grade lymphoproliferative disorder. When therapy is indicated, alkylating agents, nucleoside analogs, and rituximab are reasonable choices. Several factors, including the presence of cytopenias, need for rapid disease control, candidacy for ASCT, age, and comorbidities, should be taken into consideration when choosing the most appropriate primary treatment.
Absence of TH1 or TH2 Cytokine Differentiation After Measles Vaccine Virus Immunization Failure
Guerrero, Rubén Bonilla , Dhiman, Neelam , O’Kane, Dennis J., Poland, Gregory A., Jacobson, Robert M.

Clinical Pharmacology & Therapeutics | February 16, 2005 | Volume: 73 | Issue: 2 | Pages: No page available

10.1016/s0009-9236(03)90484-x Get It

Clinical Pharmacology & Therapeutics (2003) 73, P35–P35; doi:
2004 Where Do We Go from Here?—Summary of Working Group Discussions on Thyroid Function and Gestational Outcomes
Hollowell, Joseph G., LaFranchi, Stephen, Smallridge, Robert C., Spong, Catherine Y., Haddow, James E. , Boyle, Coleen A.

Thyroid | February 1, 2005 | Volume: 15 | Issue: 1 | Pages: 72-76

10.1089/thy.2005.15.72 | PMID 15687826 Get It

Thyroid Function Inside and Outside of Pregnancy: What Do We Know and What Don't We Know?
Smallridge, Robert C., Glinoer, Daniel, Hollowell, Joseph G., Brent, Gregory A.

Thyroid | February 1, 2005 | Volume: 15 | Issue: 1 | Pages: 54-59

10.1089/thy.2005.15.54 | PMID 15687824 Get It

Images in vascular medicine
Wysokiński, Waldemar E. , McBane, Robert D. , Wysokinski, Waldemar , McBane, Robert

Vascular Medicine | January 29, 2005 | Volume: 9 | Issue: 4 | Pages: 315-317

10.1191/1358863x04vm567xx | PMID 15678627 Get It