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Charles Nelson

Publications and source records attributed to Charles Nelson.

10 recordsLinked to original sources
PubMed2006

Transcriptomics tool for the human Schistosoma blood flukes using microarray gene expression profiling.

We report the design, fabrication, and validation of a microarray covering the majority of the Schistosoma japonicum and Schistosoma mansoni transcriptomes. The oligonucleotide microarray contains 12,166 S. mansoni and 7055 S. japonicum target sequences. A confidence threshold of <or=0.001 (P value) was used in all analyses. The cross hybridization potential of the microarray was representative of 10,362 probes detected in both channels, while 12,052 probes hybridised to S. japonicum and 11,254 probes hybridised to S. mansoni. Differential hybridisation consisted of 3422 probes to S. mansoni mRNA and 3103 probes to S. japonicum mRNA. Important biological functions, such as transport, metabolism, immune evasion and host-parasite immunological interplay, cell communication, and sexual maturation are represented on this microarray. This is the first microarray commercially manufactured for studying schistosomes, and the large size and verified quality of the resource demonstrate its power for characterising the schistosome transcriptome.

Animals↗
PubMed2006

Comparison of fluorodeoxyglucose positron emission tomography and (111)indium-white blood cell imaging in the diagnosis of periprosthetic infection of the hip.

We aimed to compare the accuracy of fluorodeoxyglucose positron emission tomography (FDG-PET) with technetium-99m sulfur colloid (111)indium-labeled white blood cell scintigraphy (TcSC-Ind BM/WBC) in diagnosis of periprosthetic infection. Eighty-nine patients with 92 painful hip prostheses were recruited prospectively and given the option of undergoing either combined FDG-PET and TcSC-Ind BM/WBC or FDG-PET only. FDG-PET correctly diagnosed 20 of the 21 infected cases (sensitivity, 95.2%) and ruled out infection in 66 of the 71 aseptic hips (specificity, 93%) corresponding to a positive predictive value of 80% (20/25) and a negative predictive value of 98.5% (66/67). TcSC-Ind BM/WBC correctly identified 5 of the 10 infected cases (sensitivity, 50%) and 39 of 41 aseptic cases (specificity, 95.1%) corresponding to a positive and negative predictive values of 41.7% (5/12 cases) and 88.6% (39/44 cases), respectively. Based on these preliminary results, FDG-PET appears to be a promising diagnostic tool for distinguishing septic from aseptic painful hip prostheses.

Adult↗
PubMed2005

The influence of hostility and family history of cardiovascular disease on autonomic activation in response to controllable versus noncontrollable stress, anger imagery induction, and relaxation imagery.

Autonomic activation in response to controllable versus noncontrollable stress, anger imagery induction, and relaxation imagery was studied among 80 participants between the ages of 18 and 34 years. Participants differed in level of trait hostility and family history of cardiovascular disease. Results were obtained through power spectral analyses of electrocardiograph R-R intervals, which produced an index of autonomic nervous system activation. For both male and female populations, parasympathetic regulation was diminished during anger induction for individuals with high levels of trait hostility and having a family history of cardiovascular disease. Similar results were obtained for women during the uncontrolled stress condition. Based on family history of cardiovascular disease and trait hostility, men responded differentially to relaxation imagery induction, whereas no differences were found among females.

Adult↗
PubMed2004

Transcriptional profiling of genes responsive to abscisic acid and gibberellin in rice: phenotyping and comparative analysis between rice and Arabidopsis.

We collected and completely sequenced 32,127 full-length complementary DNA clones from Oryza sativa L. ssp. japonica cv. "Nipponbare." Mapping of these clones to genomic DNA revealed approximately 20,500 transcriptional units (TUs) in the rice genome. For each TU, we selected 60-mers using an algorithm that took into account some DNA conditions such as base composition and sequence complexity. Using in situ synthesis technology, we constructed oligonucleotide arrays with these TUs on glass slides. We targeted RNAs prepared from normally grown rice callus and from callus treated with abscisic acid (ABA) or gibberellin (GA). We identified 200 ABA-responsive and 301 GA-responsive genes, many of which had never before been annotated as ABA or GA responsive in other expression analysis. Comparison of these genes revealed antagonistic regulation of almost all by both hormones; these had previously been annotated as being responsible for protein storage and defense against pathogens. Comparison of the cis-elements of genes responsive to one or antagonistic to both hormones revealed that the antagonistic genes had cis-elements related to ABA and GA responses. The genes responsive to only one hormone were rich in cis-elements that supported ABA and GA responses. In a search for the phenotypes of mutants in which a retrotransposon was inserted in these hormone-responsive genes, we identified phenotypes related to seed formation or plant height, including sterility, vivipary, and dwarfism. In comparison of cis-elements for hormone response genes between rice and Arabidopsis thaliana, we identified cis-elements for dehydration-stress response as Arabidopsis specific and for protein storage as rice specific.

Abscisic Acid↗
PubMed2004

Impact of scar thickness on the assessment of viability using dobutamine echocardiography and thallium single-photon emission computed tomography: a comparison with contrast-enhanced magnetic resonance imaging.

OBJECTIVES: We sought to determine whether the transmural extent of scar (TES) explains discordances between dobutamine echocardiography (DbE) and thallium single-photon emission computed tomography (Tl-SPECT) in the detection of viable myocardium (VM). BACKGROUND: Discrepancies between DbE and Tl-SPECT are often attributed to differences between contractile reserve and membrane integrity, but may also reflect a disproportionate influence of nontransmural scar on thickening at DbE. METHODS: Sixty patients (age 62 +/- 12 years; 10 women and 50 men) with postinfarction left ventricular dysfunction underwent standard rest-late redistribution Tl-SPECT and DbE. Viable myocardium was identified when dysfunctional segments showed Tl activity >60% on the late-redistribution image or by low-dose augmentation at DbE. Contrast-enhanced magnetic resonance imaging (ceMRI) was used to divide TES into five groups: 0%, <25%, 26% to 50%, 51% to 75%, and >75% of the wall thickness replaced by scar. RESULTS: As TES increased, both the mean Tl uptake and change in wall motion score decreased significantly (both p < 0.001). However, the presence of subendocardial scar was insufficient to prevent thickening; >50% of segments still showed contractile function with TES of 25% to 75%, although residual function was uncommon with TES >75%. The relationship of both tests to increasing TES was similar, but Tl-SPECT identified VM more frequently than DbE in all groups. Among segments without scar or with small amounts of scar (<25% TES), >50% were viable by SPECT. CONCLUSIONS: Both contractile reserve and perfusion are sensitive to the extent of scar. However, contractile reserve may be impaired in the face of no or minor scar, and thickening may still occur with extensive scar.

Adrenergic beta-Agonists↗
PubMed2004

Total knee arthroplasty in patients on workers' compensation: a matched cohort study with an average follow-up of 4.5 years.

Little information in the literature exists regarding the outcome of total knee arthroplasty (TKA) in patients who are on workers' compensation (WC). Twenty-one WC patients who underwent 23 TKA procedures (cases) were compared with 16 randomly selected, age-matched control patients (controls) undergoing 21 TKA procedures. The mean follow-up was 56 months (34-112 months) for both groups. The results were evaluated using the scoring system of the Knee Society (KSS). Significant improvements in KSS were noted in both groups, and all subjects indicated that they would undergo the procedure again. The KSS were statistically better in the control group relative to the WC group. There was no difference in range of motion, stability, or radiographic alignment. Despite high satisfaction with the results of surgery in both groups, only 5 of 21 patients in the WC group returned to their previous occupation. TKA improves pain and function scores in WC patients with end-stage knee disease. Understanding how WC issues affect the results of TKA is critical to the selection of appropriate surgical candidates.

Arthroplasty, Replacement, Knee↗
PubMed2002

Corepressor-dependent silencing of chromosomal regions encoding neuronal genes.

The molecular mechanisms by which central nervous system-specific genes are expressed only in the nervous system and repressed in other tissues remain a central issue in developmental and regulatory biology. Here, we report that the zinc-finger gene-specific repressor element RE-1 silencing transcription factor/neuronal restricted silencing factor (REST/NRSF) can mediate extraneuronal restriction by imposing either active repression via histone deacetylase recruitment or long-term gene silencing using a distinct functional complex. Silencing of neuronal-specific genes requires the recruitment of an associated corepressor, CoREST, that serves as a functional molecular beacon for the recruitment of molecular machinery that imposes silencing across a chromosomal interval, including transcriptional units that do not themselves contain REST/NRSF response elements.

Animals↗
PubMed2002

Impaction grafting and wire mesh for uncontained defects in revision knee arthroplasty.

The current authors review the results of 17 revision total knee arthroplasties in 14 patients in whom large uncontained defects were treated with impaction allografting and molded wire mesh for containment. Knee Society clinical scores increased from an average of 47 points to 95 points and function scores increased from 48 points to 73 points at the most recent followup. No patients required revision surgery, although, nonprogressive tibial radiolucency has been observed in three patients. One patient required open reduction and internal fixation of a periprosthetic supracondylar femur fracture. One patient with an acute postoperative infection with Staphylococcus epidermidis was treated successfully with irrigation and debridement with retention of the implant. Impaction grafting with wire mesh containment for large uncontained defects in revision total knee arthroplasty is an effective method of treating massive uncontained bone loss in revision total knee arthroplasty.

Aged↗
PubMed2002

Relations of intrinsic spirituality with health status and symptom interference.

The purpose of this study was to examine the relationships between spiritual experience and current health status and between spiritual experience and subjective experience of symptom interference. Symptom interference is the extent to which symptoms of physical or psychological illness limited participants' activities of daily living. Participants were 49 volunteers who were enrolled in a spiritual fitness class at a variety of denominational Christian churches in Plano, Texas. The sample ranged in age from 22 to 65 years, and 84% were women. The Index of Core Spiritual Experiences and the Medical Symptoms Checklist were administered. Current health status and symptom interference were utilized from the self-report checklist. It was predicted that Index scores would be significantly different based on participants' health status and that Index scores would correlate significantly with participants' ratings of symptom interference. Analysis indicated that Index scores were significantly higher (p = .02) for participants with no current medical diagnosis than for those currently experiencing either a life-threatening or a chronic medical or psychological disorder. Also, the percentage-bend correlation between Index scores and scores for interference of symptoms in daily life was significant ((r)Pb = -.33, p = .02). These results suggest that the report of core spiritual experiences may be related to better current health status. These findings have implications for understanding the role of spirituality in the prevention of illness and in an individual's ability to cope with illness.

Adaptation, Psychological↗