Biomedical subjects

Richard E Harris

Publications and source records attributed to Richard E Harris.

23 records · Page 2Linked to original sources

PubMed2003

Subgrouping of fibromyalgia patients on the basis of pressure-pain thresholds and psychological factors.

OBJECTIVE: Although the American College of Rheumatology (ACR) criteria for fibromyalgia are used to identify individuals with both widespread pain and tenderness, individuals who meet these criteria are not a homogeneous group. Patients differ in their accompanying clinical symptoms, as well as in the relative contributions of biologic, psychological, and cognitive factors to their symptom expression. Therefore, it seems useful to identify subsets of fibromyalgia patients on the basis of which of these factors are present. Previous attempts at identifying subsets have been based solely on psychological and cognitive features. In this study, we attempt to identify patient subsets by incorporating these features as well as the degree of hyperalgesia/tenderness, which is a key neurobiologic feature of this illness. METHODS: Ninety-seven individuals meeting the ACR criteria for fibromyalgia finished the same battery of self-report and evoked-pain testing. Analyzed variables were obtained from several domains, consisting of 1) mood (evaluated by the Center for Epidemiologic Studies Depression Scale [for depression] and the State-Trait Personality Inventory [for symptoms of trait-related anxiety]), 2) cognition (by the catastrophizing and control of pain subscales of the Coping Strategies Questionnaire), and 3) hyperalgesia/tenderness (by dolorimetry and random pressure-pain applied at suprathreshold values). Cluster analytic procedures were used to distinguish subgroups of fibromyalgia patients based on these domains. RESULTS: Three clusters best fit the data. Multivariate analysis of variance (ANOVA) confirmed that each variable was differentiated by the cluster solution (Wilks' lambda [degrees of freedom 6,89] = 0.123, P < 0.0001), with univariate ANOVAs also indicating significant differences (all P < 0.05). One subgroup of patients (n = 50) was characterized by moderate mood ratings, moderate levels of catastrophizing and perceived control over pain, and low levels of tenderness. A second subgroup (n = 31) displayed significantly elevated values on the mood assessments, the highest values on the catastrophizing subscale, the lowest values for perceived control over pain, and high levels of tenderness. The third group (n = 16) had normal mood ratings, very low levels of catastrophizing, and the highest level of perceived control over pain, but these subjects showed extreme tenderness on evoked-pain testing. CONCLUSION: These data help support the clinical impression that there are distinct subgroups of patients with fibromyalgia. There appears to be a group of fibromyalgia patients who exhibit extreme tenderness but lack any associated psychological/cognitive factors, an intermediate group who display moderate tenderness and have normal mood, and a group in whom mood and cognitive factors may be significantly influencing the symptom report.

Adolescent↗

PubMed2003

Low risk of graft-versus-host disease with transplantation of CD34 selected peripheral blood progenitor cells from alternative donors for Fanconi anemia.

OBJECTIVES: Transplant results for Fanconi anemia with alternative-donor bone marrow transplantation currently entail a high incidence of graft failure and graft-versus-host disease (GVHD). The authors sought to improve outcome in this disease category with alternative donors with a 5-6/6 antigen match by transplantation of highly purified peripheral blood progenitor cells (PBPC) using the Isolex 300i v2.5 device as a means of T-cell depletion to lessen the risk of GVHD. METHODS: All Fanconi anemia patients (n = 8) received the same preparative regimen that included total body irradiation (450 cGy), Cytoxan (20 mg/kg), ATGAM, and fludarabine (120 mg/m2). The cell dose of CD34+ cells was a median of 11.4 x 10(6)/kg; the cell dose of CD3+ cells was a median of 1.9 x 10(4)/kg. Primary engraftment was rapid in all patients, with neutrophil recovery occurring at a median of day 10 and platelet count more than 50,000 on day 27. Two patients subsequently had secondary graft failure. Despite lack of cyclosporine GVHD prophylaxis, only two patients developed acute GVHD (both grade I), and no patients developed chronic GVHD. Three patients died: one at day 59 secondary to disseminated fungal infection, the second at day 196 during a second transplant, and the third at day 202 due to graft failure. With a median follow-up of 12 months, the overall survival was 58 +/- 18%. CONCLUSIONS: Transplantation of CD34-selected PBPCs from alternative donors results in a very low risk of GVHD in patients with Fanconi anemia.

Adolescent↗

PubMed2002

A comparison of allogeneic and autologous bone marrow transplantation for lymphoblastic lymphoma.

Lymphoblastic lymphoma (LBL) is a rare, clinically aggressive neoplasm of the young that frequently involves the bone marrow (BM) and/or central nervous system. Because LBL is similar to acute lymphoblastic leukemia, some centers prefer allogeneic hematopoietic stem cell (SC) transplantation to autologous SC transplantation. We retrospectively analyzed outcomes for patients who underwent autologous (auto, n = 128) or HLA-identical sibling (allo, n = 76) SC transplantations from 1989 to 1998 and were reported to International Bone Marrow Transplant Registry (IBMTR) or Autologous Blood and Marrow Transplant Registry (ABMTR). Allo stem cell transplant (SCT) recipients had higher treatment-related mortality (TRM) at 6 months (18% versus 3%, P =.002), and this disadvantage persisted at 1 and 5 years. Early relapse rates after alloSC transplantation and autoSC transplantation were similar, but significantly lower relapse rates were observed in alloSCT recipients at 1 and 5 years (32% versus 46%, P =.05; and 34% versus 56%, P =.004, respectively). No differences were noted in lymphoma-free survival rates between alloSC transplantations and autoSC transplantations (5-year rates 36% versus 39%, P =.82). AutoSCT recipients had higher overall survival at 6 months (75% versus 59%, P =.01), but survival did not significantly differ between the 2 groups at 1 and 5 years (60% versus 49%, P =.09; 44% versus 39%, P =.47, respectively). Multivariate analyses to account for confounding factors confirmed these results. Independent of SCT type, BM involvement at the time of transplantation and disease status more advanced than first complete remission were associated with inferior outcomes. In summary, alloSC transplantation for LBL is associated with fewer relapses than with autoSC transplantation, but higher TRM offsets any potential survival benefit.

Adolescent↗

PubMed2002

Unrelated donor marrow transplantation for myelodysplastic syndromes: outcome analysis in 510 transplants facilitated by the National Marrow Donor Program.

Between April 1988 and July 1998, 510 patients with myelodysplastic syndromes (MDS) underwent unrelated donor bone marrow transplantation (BMT) facilitated by the National Marrow Donor Program. Median age was 38 years (range, <1-62 years). Several conditioning regimens and graft-versus-host disease (GVHD) prophylaxis methods were used, and T-cell depletion was used in 121 patients. Donors were serologically matched for HLA-A, -B, and -DRB1 antigens for 74% of patients. Of 437 patients evaluable for engraftment, 24 (5% cumulative incidence, with 95% confidence interval [CI] of 3%-7%) failed to engraft, and an additional 33 (8% cumulative incidence; 95% CI, 6%-10%) had late graft failure. Grades II to IV GVHD developed in 47% of patients (95% CI, 43%-49%), and limited and extensive chronic GVHD developed at 2 years in 27% (95% CI, 24%-30%). The incidence of relapse at 2 years was 14% (95% CI, 11%-17%). Greater relapse was independently associated with advanced MDS subtype and no acute GVHD. The estimated probability of disease-free survival (DFS) at 2 years was 29% (95% CI, 25%-33%). Improved DFS was independently associated with less advanced MDS subtype, higher cell dose, recipient cytomegalovirus (CMV) seronegativity, shorter interval from diagnosis to transplantation, and transplantation in recent years. Common causes of death were treatment-related complications accounting for 82% of fatalities. The 2-year cumulative incidence of treatment-related mortality (TRM) was 54% (95% CI, 53%-61%). Sixty-nine percent of TRM occurred within the first 100 days, and 93% occurred within the first year of transplantation. Higher TRM was independently associated with older recipient and donor age, HLA mismatch, and recipient CMV seropositivity. This study demonstrates that unrelated donor BMT cures a significant proportion of patients with MDS. TRM is the major problem limiting the success of unrelated donor BMT in MDS. The observations made in this study should facilitate the design of prospective trials aimed at improving the results of unrelated donor stem cell transplantation for MDS.

Adolescent↗

PubMed2002

Dissociated retinal neurons form periodically active synaptic circuits.

Throughout the developing nervous system, immature circuits generate rhythmic activity patterns that influence the formation of adult networks. The cellular mechanisms underlying this spontaneous, correlated activity can be studied in dissociated neuronal cultures. Using calcium imaging and whole cell recording, we showed that cultured dissociated mammalian retinal neurons form networks that produce spontaneous, correlated, highly periodic activity. As the culture matures, the spatial correlations of the periodic calcium transients evolve from being highly synchronized across neighboring cells to propagating across the culture in a wavelike manner reminiscent of retinal waves recorded in vivo. Spontaneous calcium transients and synaptic currents were blocked either by cadmium, tetrodotoxin, or the glutamate receptor antagonist 6,7-dinitroquinoxaline, indicating that the periodic activity was driven primarily by synaptic transmission between retinal ganglion cells. Evoked responses between pairs of ganglion cells exhibited paired-pulse synaptic depression, and the time constant of recovery from this depression was similar to the interval between periodic events. These results suggest that synaptic depression may regulate the frequency of network activity. Together, these findings provide insight into how networks containing primarily excitatory connections generate highly correlated activity.

Amacrine Cells↗