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Biomedical subjects

James Johnson

Publications and source records attributed to James Johnson.

16 recordsLinked to original sources
PubMed2004

High-dose chemotherapy with autologous stem-cell rescue in the treatment of patients with recurrent non-cerebellar primitive neuroectodermal tumors.

BACKGROUND: Recurrent non-cerebellar primitive neuroectodermal tumors (PNETs) carry a dismal prognosis when treated with conventional chemotherapy alone. XSWe tested the efficacy of high-dose chemotherapy (HDC) followed by autologous stem-cell rescue (ASCR) in this setting. PROCEDURE: Eligibility mandated either minimal residual disease or evidence of chemosensitivity before HDC. Conditioning consisted of carboplatin (CBDCA) (500 mg/m(2) or AUC = 7 mg/ml min using the Calvert formula) on days -8 to -6, thiotepa (300 mg/m(2)), and etoposide (250 mg/m(2)) on days -5 to -3. Irradiation was given post HDC selectively. RESULTS: Among 17 patients treated in this study, there were eight pineoblastoma(s) (pineo), seven cortical PNETs, and two arising elsewhere. Relapse was either local (nine) or metastatic to the brain (four) or spine (four). Two patients received HDC as the sole therapy for recurrence; additionally, eight underwent surgical debulking before HDC, and nine received irradiation, including six after HDC. Median age at ASCR was 3.9 years. Two patients died of toxicity (11%) and ten experienced tumor relapse (range: 23-361 days post ASCR). Five patients with cortical PNETs remain alive disease-free (median follow-up: 8.3 years); four of them received irradiation post HDC. The difference in 5-year event-free survival (EFS) between patients with pineo and other supratentorial PNETs was significant (0 vs. 62.5 +/- 17%, P = 0.0065). Both surgery at relapse and irradiation post HDC were favorable prognostic factors (P = 0.006 and 0.01, respectively). CONCLUSIONS: Patients with recurrent cortical PNETs can be cured with this strategy. Surgical debulking before, and irradiation after HDC play an important role in treatment success.

Adolescent↗
PubMed2004

Functional protein nanoarrays for biomarker profiling.

The use of microarrays for parallel screening of nucleic acid profiles has become an industry standard. Similar efforts for screening protein-protein interactions are gaining momentum, however, they remain limited by the requirement for relatively large sample volumes. One strategy for overcoming this problem is to significantly decrease the size and consequently the sample volume of the protein interaction assay. We report here on our progress over the last two years in the construction of ultraminiaturized, functional protein capture assays. Each one micron spot in these array-based assays covers less than 1/1000(th) of the surface area of a conventional microarray spot while still maintaining enough antibodies to provide a useful dynamic range. These nanoarray assays can be read by conventional optical fluorescence microscopy as well as by novel label-free methods such as atomic force microscopy. The size reduction realized by functional protein nanoarrays also creates opportunities for novel applications including highly multiplexed single cell analysis and integration with microfluidics and other "lab-on-a-chip" technologies.

Biomarkers↗
PubMed2003

Iliac crest osteocutaneous flap reconstruction for ameloblastoma of the mandible in a patient with bilateral peronea artery magna: case report.

Success of oromandibular reconstructions is increasingly achieved through fundamental microvascular techniques that incorporate innovative adjunct modalities. We report a complex case of a large anterior mandibular plexiform ameloblastoma reconstructed with an iliac crest free flap in a young woman with bilateral peronea arteria magna. This article serves to highlight the application of several new technologies in an effort to provide a functional and cosmetically acceptable result.

Adult↗
PubMed2003

wCLUTO: a Web-enabled clustering toolkit.

As structural and functional genomics efforts provide the biological community with ever-broadening sets of interrelated data, the need to explore such complex information for subtle relationships expands. We present wCLUTO, a Web-enabled version of the stand-alone application CLUTO, designed to apply clustering methods to genomic information. Its first application is focused on the clustering transcriptome data from microarrays. Data can be uploaded by the user into the clustering tool, a choice of several clustering methods can be made and configured, and data are presented to the user in a variety of visual formats, including a three-dimensional "mountain" view of the clusters. Parameters can be explored to rapidly examine a variety of clustering results, and the resulting clusters can be downloaded either for manipulation by other programs or to be saved in a format for publication.

Algorithms↗
PubMed2003

Influence of site preparation methods on the pain reported during palatal infiltration using the Wand Local Anesthetic System.

PURPOSE: To compare different site preparation methods and their effect on the pain reported during local anesthetic infiltration at the palatal site. The study compared the following tissue site preparation methods: application of a topical anesthetic agent, pressure anesthesia achieved with a cotton tip applicator, a combination of both methods, and neither method (non-placebo control). MATERIALS AND METHODS: 15 adult subjects received a total of four palatal injections, one with each type of site preparation in a randomized order over two appointments (two injections per appointment). Bilateral palatal injections were performed in a standardized manner using the uniform slow flow rate produced by the Wand Local Anesthetic System through a 30-gauge needle. Pain response was measured by subject self-report using the visual analogue scale (VAS), a quantified verbal descriptor scale (Gracely), and a comparison to prior injection experience, as well as the operator's global assessment of the subject's pain response. RESULTS: All recorded pain measurements failed to demonstrate statistical differences for the various site preparations tested. The scores for the VAS and the Gracely scales were statistically in agreement. When administering a slow flow rate of anesthetic solution at the palatal site, this study demonstrated that the intensity of pain reported by adult subjects was minimal. The low intensity of reported pain, measured in several different ways, failed to discriminate among the various site preparation methods tested.

Administration, Topical↗
PubMed2003

All-ceramic restorative system for esthetic implant-supported crowns: in vitro evaluations and clinical case report.

Patient demands for improved esthetics have prompted the development of all-ceramic restorative systems for dental implants, but material strength and restorative costs have presented clinical challenges. Therefore, a new restorative system with tooth-shaped ceramic copings for the anterior and premolar jaw regions has been introduced to address these problems. Fatigue and 17o. compression tests were conducted in vitro to assess the mechanical strength of the 6 tooth-shaped copings and several luting agents of the system. A case report on the clinical use of the components is presented. All 6 tooth-shaped copings significantly exceeded the range of forces associated with restoration in the anterior jaw. Crown-endurance limits for fatigue and 17o. compression were 70% higher and 46% higher, respectively, than the established minimum-fatigue-endurance limits in those categories. In clinical evaluation, the ceramic restorative system performed well and produced excellent results; it has potential for implant restorations in the anterior and premolar regions of the jaw.

Aluminum Oxide↗
PubMed2002

Phytanic acid, a natural peroxisome proliferator-activated receptor (PPAR) agonist, regulates glucose metabolism in rat primary hepatocytes.

Phytanic acid, a metabolite of the chlorophyll molecule, is part of the human diet and is present in normal human serum at low micromolar concentrations. It was previously shown to be a ligand of the 9-cis-retinoic acid receptor and peroxisome proliferator-activated receptor (PPAR) a. PPAR agonists are widely used in the treatment of type 2 diabetes. Here, we report that phytanic acid is not only a transactivator of PPARa, but it also acts via PPARb and PPARg in CV-1 cells that have been cotransfected with the respective full-length receptor and an acyl-CoA oxidase-PPAR-responsive element-luciferase construct. We observed that, in contrast to other fatty acids, phytanic acid at physiological concentrations enhances uptake of 2-deoxy-D-glucose in rat primary hepatocytes. This result could be explained by the increase in mRNA expression of glucose transporters-1 and -2 and glucokinase, as determined by quantitative real-time reverse transcriptase-polymerase chain reaction. Compared with the PPARg-specific agonist ciglitazone, phytanic acid exerts only minor effects on the differentiation of C3H10T1/2 cells into mature adipocytes. These results clearly demonstrate that phytanic acid acts via different PPAR isoforms to modulate expression of genes involved in glucose metabolism, thus suggesting a potential role of phytanic acid in the management of insulin resistance.

Adipocytes↗
PubMed2002

The Management Academy for Public Health: a new paradigm for public health management development.

Research has established a need to develop management skills among public health professionals. The University of North Carolina-Chapel Hill created the Management Academy for Public Health as a pilot program for this specialized training need. This article describes why a management academy for public health managers was formed, its curriculum and instructional methods, and the evaluation findings from its first year. The program sponsors hope to effect individual and organization level change, eventually leading to improved community health. Results suggest that this innovative program gives public health professionals needed skills and improves their job performance.

Curriculum↗
PubMed2002

Acyclovir cream for treatment of herpes simplex labialis: results of two randomized, double-blind, vehicle-controlled, multicenter clinical trials.

Acyclovir cream has been available for the treatment of herpes labialis in numerous countries outside the United States for over a decade. Evidence for its efficacy comes from a few small clinical trials conducted in the 1980s. To examine more comprehensively the efficacy and safety of this formulation, we conducted two independent, identical, parallel, randomized, double-blind, vehicle-controlled, large-scale multicenter clinical trials. Healthy adults with a history of frequent herpes labialis were recruited from the general population, screened for eligibility, randomized equally to 5% acyclovir cream or vehicle control, given study medication, and told to self-initiate treatment five times daily for 4 days beginning within 1 h of the onset of a recurrent episode. The number of patients who treated a lesion was 686 in study 1 and 699 in study 2. In study 1, the mean duration of episodes was 4.3 days for patients treated with acyclovir cream and 4.8 days for those treated with the vehicle control (hazards ratio [HR] = 1.23; 95% confidence interval [CI], 1.06 to 1.44; P = 0.007). In study 2, the mean duration of episodes was 4.6 days for patients treated with acyclovir cream and 5.2 days for those treated with the vehicle control (HR = 1.24; 95% CI, 1.06 to 1.44; P = 0.006). Efficacy was apparent whether therapy was initiated "early" (prodrome or erythema lesion stage) or "late" (papule or vesicle stage). There was a statistically significant reduction in the duration of lesion pain in both studies. Acyclovir cream did not prevent the development of classical lesions (progression to vesicles, ulcers, and/or crusts). Adverse events were mild and infrequent.

Acyclovir↗
PubMed2002

Surveillance for unexplained deaths and critical illnesses due to possibly infectious causes, United States, 1995-1998.

Population-based surveillance for unexplained death and critical illness possibly due to infectious causes (UNEX) was conducted in four U.S. Emerging Infections Program sites (population 7.7 million) from May 1, 1995, to December 31, 1998, to define the incidence, epidemiologic features, and etiology of this syndrome. A case was defined as death or critical illness in a hospitalized, previously healthy person, 1 to 49 years of age, with infection hallmarks but no cause identified after routine testing. A total of 137 cases were identified (incidence rate 0.5 per 100,000 per year). Patients' median age was 20 years, 72 (53%) were female, 112 (82%) were white, and 41 (30%) died. The most common clinical presentations were neurologic (29%), respiratory (27%), and cardiac (21%). Infectious causes were identified for 34 cases (28% of the 122 cases with clinical specimens); 23 (68%) were diagnosed by reference serologic tests, and 11 (32%) by polymerase chain reaction-based methods. The UNEX network model would improve U.S. diagnostic capacities and preparedness for emerging infections.

Adolescent↗
PubMed1998

Reactivity of the Verdoheme Analogues, 5-Oxaporphyrin Complexes of Cobalt(II) and Zinc(II), with Nucleophiles: Opening of the Planar Macrocycle by Alkoxide Addition To Form Helical Complexes.

The 5-oxaporphyrin macrocycle is a modified porphyrin (with an oxygen atom replacing a meso-methine unit) that is produced during heme degradation in biological and chemical systems. We have undertaken an investigation into the chemical reactivity of metal complexes of this macrocycle. Here we report that the diamagnetic zinc(II) and paramagnetic cobalt(II) verdoheme analogues, [Zn(II)(OEOP)](O(2)CCH(3)) and [Co(II)(OEOP)](PF(6)) (OEOP is the monoanion of octaethyl-5-oxaporphyrin), undergo ring opening when treated with alkoxide ions. The zinc(II) complex Zn(II)(OEBOMe), where OEBOMe is the dianion of octaethylmethoxybiliverdin, is sufficiently stable to be isolated in crystalline form, but the cobalt(II) analogue, Co(II)(OEBOMe), is less stable and has been characterized primarily by (1)H NMR spectroscopy in solution. The reactions are accompanied by a color change from blue-green for the verdoheme complexes to yellow-green for the ring-opened compounds. The ring-opened product Zn(II)(OEBOMe) has been subjected to a crystallographic study which reveals that the complex contains a four-coordinate zinc(II) ion whose geometry is significantly controlled by the helical tetrapyrrole ligand so that tetrahedral coordination is not achieved. The structure of this complex is compared to that of a closely related free ligand and those of copper and cobalt complexes of tetrapyrrole ligands that also form helical complexes.

Journal Article↗
PubMedDate not supplied

Meniscal ossicles in large non-domestic cats.

Radiographs of the stifles of 6 species of 34 large, non-domestic cats were reviewed foremost for the presence of meniscal ossicles and then for the presence of the other potential four sesamoids. The animals in the review included 12 lions, 7 tigers, 7 cougars, 3 leopards, 3 bobcats, and 2 jaguars. Fluoroscopy, arthrography, computed tomography, necropsy, and histology were also used to evaluate the stifles of one tiger after euthanasia. Ossicles were found in the region of the cranial horn of the medial meniscus in most of the lions, tigers, leopards, and jaguars. These ossicles were found in half of the cougars but in none of the bobcats. Among the large, non-domestic cats, meniscal ossicles had been reported previously only in Bengal tigers. The lions, tigers, and leopards having meniscal ossicles appeared to have a lateral but often not a medial fabella of the gastrocnemius muscle, an observation previously unreported. Popliteal sesamoids and patellas were present in all the skeletally mature cats.

Animals↗