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S McCann

Publications and source records attributed to S McCann.

At least 19 recordsLinked to original sources
PubMed2001

Changes in regional brain glucose metabolism measured with positron emission tomography after paroxetine treatment of major depression.

OBJECTIVE: Depression is commonly associated with frontal hypometabolic activity accompanied by hypermetabolism in certain limbic regions. It is unclear whether successful antidepressant treatments reverse these abnormalities or create new resting levels of metabolism. The aim of the present study was to assess the effects of successful paroxetine treatment on regional glucose metabolism in patients with major depression. METHOD: Positron emission tomography with [(18)F]fluorodeoxyglucose was performed on 13 male patients before and after 6 weeks of paroxetine therapy. Resting state scans were also acquired under similar conditions in 24 healthy male subjects for comparison. RESULTS: After successful paroxetine therapy, increased glucose metabolism occurred in dorsolateral, ventrolateral, and medial aspects of the prefrontal cortex (left greater than right), parietal cortex, and dorsal anterior cingulate. Areas of decreased metabolism were noted in both anterior and posterior insular regions (left) as well as right hippocampal and parahippocampal regions. In comparison to metabolism levels in a group of healthy volunteers, the increase in prefrontal metabolic activity represented a normalization of previously reduced metabolic activity, whereas the reduction in pregenual anterior cingulate activity represented a decrease from previously elevated metabolic levels. CONCLUSIONS: These results provide further support for a dysfunction in cortical-limbic circuitry in depression, which is at least partly reversed after successful paroxetine treatment.

Adult↗
PubMed2000

Cyclosporin A and short-term methotrexate versus cyclosporin A as graft versus host disease prophylaxis in patients with severe aplastic anemia given allogeneic bone marrow transplantation from an HLA-identical sibling: results of a GITMO/EBMT randomized trial.

A randomized trial was carried out comparing cyclosporin A (CsA) and short-term methotrexate (MTX) versus CsA alone for graft versus host disease (GVHD) prophylaxis in patients with severe aplastic anemia (SAA) undergoing allogeneic bone marrow transplantation (BMT) from a compatible sibling. Seventy-one patients (median age, 19 years; range, 4-46 years) were randomized to receive either CsA and MTX or CsA alone for the first 3 weeks after BMT. Subsequently, both groups received CsA orally, with gradual drug reduction until discontinuation 8 to 12 months after BMT. Patients randomized in both arms had comparable characteristics and received the same preparative regimen (ie, cyclophosphamide 200 mg/kg over 4 days). The median time for neutrophil engraftment was 17 days (range, 11-31 days) and 12 days (range, 4-45 days) for patients in the CsA/MTX group and the CsA alone group, respectively (P =.01). No significant difference was observed in the probability of either grade 2, grade 3, or grade 4 acute GVHD or chronic GVHD developing in the 2 groups. The Kaplan-Meier estimates of 1-year transplantation-related mortality rates for patients given either CsA/MTX or CsA alone were 3% and 15%, respectively (P =.07). With a median follow-up of 48 months from BMT, the 5-year survival probability is 94% for patients in the CsA/MTX group and 78% for those in the CsA alone group (P =. 05). These data indicate that the use of CsA with MTX is associated with improved survival in patients with SAA who receive transplants from compatible siblings. (Blood. 2000;96:1690-1697)

Adolescent↗
PubMed2000

Treatment of acquired severe aplastic anemia: bone marrow transplantation compared with immunosuppressive therapy--The European Group for Blood and Marrow Transplantation experience.

Patients with severe aplastic anemia (SAA) can be successfully treated with bone marrow transplantation (BMT) or immunosuppressive therapy (IS). The current outcome using both forms of therapy among 3,669 patients treated in Europe between 1976 and 1998 is reviewed. Significant progress has been made and the overall risk of failure is now low, with survival rates greater than 80% for both treatments. Chronic graft-versus-host disease (GvHD) remains a problem for BMT patients, and carries a high risk of lethal complications. On the other hand, IS patients are exposed to late failure due to relapse or clonal/malignant diseases. First-line BMT from identical siblings is compared with IS therapy in an intent-to-treat analysis of 1,765 patients, regardless of subsequent transplant status. The outcome of SAA patients has improved considerably over time and is influenced by patient variables such as severity of the disease and age, but also by the choice of the initial treatment.

Anemia, Aplastic↗
PubMed2000

Lipopolysaccharide-induced leptin release is not mediated by nitric oxide, but is blocked by dexamethasone.

The adipocyte hormone, leptin, has homology with tumor necrosis factor-alpha (TNF-alpha) and the leptin receptor (OB-Rb) has homology with the interleukin(IL)-6 receptor. Lipopolysaccharide (LPS) from gram-negative bacteria stimulates the release of many pro-inflammatory cytokines, such as TNF-alpha, IL-1 and IL-6, among others. To test the hypothesis that LPS would also stimulate the release of leptin, LPS (0.6 mg/kg) was injected intravenously into conscious male rats bearing external jugular venous catheters. Vehicle (0.9% NaCl) was injected into control animals. Blood samples (0.3 ml) were drawn immediately before injection and every 10 min afterwards for 120 min. Plasma leptin concentrations increased gradually in the LPS-treated rats, reaching a peak at 120 min of nearly twice the starting level. To determine if this release was mediated by nitric oxide (NO), nitroarginine methyl ester (NAME), an inhibitor of NO synthase, was injected at doses of 11 or 23 mg/kg (i. v.). The lower dose decreased plasma leptin slightly, whereas the higher dose of NAME increased plasma leptin at 110 min but had no effect on LPS-induced leptin release. On the other hand, dexamethasone (DEX) (0.85 mg/kg), a synthetic glucocorticoid, injected 15 min before LPS, decreased LPS-induced leptin release by 80% (p < 0.001). The results indicate that LPS is a stimulant of leptin release, that NO has little control over basal or LPS-induced leptin release, but that glucocorticoids, epitomized by DEX, largely block LPS-induced leptin release. Increased release of leptin during infection may contribute to the decreased feeding, altered hormonal release and metabolic changes that occur during infection.

Animals↗
PubMed2000

Current results of bone marrow transplantation in patients with acquired severe aplastic anemia. Report of the European Group for Blood and Marrow transplantation. On behalf of the Working Party on Severe Aplastic Anemia of the European Group for Blood and Marrow Transplantation.

We have analyzed 2,002 patients grafted in Europe between 1976 and 1998 from an identical twin (n = 34), from an HLA-identical sibling (n = 1,699) or from an alternative donor (n = 269), which included unrelated and family mismatched donors. The proportions of patients surviving in these three groups are, respectively, 91, 66 and 37%: major causes of failure were acute graft-versus host disease (GvHD) (11%), infection (12%), pneumonitis (4%), rejection (4%). In multivariate Cox analysis, factors predicting outcome were patient's age (p < 0.0001), donor type (p < 0.0001), interval between diagnosis and bone marrow transplantation (BMT) (p < 0.0005), year of BMT (p = 0.0005) and female donor for a male recipient (p = 0.02). Patients were then divided in two groups according to the year of BMT: up to or after 1990. The overall death rate dropped from 43 to 24% (p < 0.00001). Improvements were seen mostly for grafts from identical siblings (from 54 to 75%, p < 0.0001), and less so for alternative-donor grafts (from 28 to 35%; p = 0.07). Major changes have occurred in the BMT protocol: decreasing use of radiotherapy in the conditioning regimen (from 35 to 24%; p < 0.0001) and increasing use of cyclosporin (with or without methotrexate) for GvHD prophylaxis (from 70 to 98%; p < 0.0001). In conclusion, the outcome of allogeneic BMT for patients with severe aplastic anemia has considerably improved over the past two decades: young patients, grafted early after diagnosis from an identical sibling, have currently an over 80% chance of long-term survival. Transplants from twins are very successful as well. The risk of complications with alternative donor transplants is still high.

Acute Disease↗
PubMed1999

Prospective randomized multicenter study comparing cyclosporin alone versus the combination of antithymocyte globulin and cyclosporin for treatment of patients with nonsevere aplastic anemia: a report from the European Blood and Marrow Transplant (EBMT) Severe Aplastic Anaemia Working Party.

We report the results of the first prospective randomized multicenter study of immunosuppressive treatment in patients with previously untreated nonsevere aplastic anemia (AA) as defined by a neutrophil count of at least 0.5 x 10(9)/L and transfusion dependence. Patients were randomized to receive cyclosporin (CSA) alone or the combination of horse antithymocyte globulin ([ATG] Lymphoglobuline; Merieux, Lyon, France) and CSA. The endpoint of the study was the hematologic response at 6 months. One hundred fifteen patients were randomized and assessable with a median follow-up period of 36 months; 61 received CSA and 54 ATG and CSA. In the CSA group, the percentage of complete and partial responders was 23% and 23%, respectively, for an overall response rate of 46%. A significantly higher overall response rate of 74% was found in the ATG and CSA group, with 57% complete and 17% partial responders (P =. 02). Compared with CSA alone, the combination of ATG and CSA resulted in a significantly higher median hemoglobin level and platelet count at 6 months. Fewer patients required a second course of treatment before 6 months due to a nonresponse. In the CSA group, 15 of 61 (25%) patients required a course of ATG before 6 months because of disease progression, compared with only 3 of 54 (6%) in the ATG and CSA group. The survival probabilities for the two groups were comparable, 93% (CSA group) and 91% (ATG and CSA group), but at 180 days, the prevalence of patients surviving free of transfusions, which excluded patients requiring second treatment because of nonresponse, death, disease progression, or relapse, was 67% in the CSA group and 90% in the ATG and CSA group (P =.001). We conclude that the combination of ATG and CSA is superior to CSA alone in terms of the hematologic response, the quality of response, and early mortality, and a second course of immunosuppression is less frequently required.

Adolescent↗
PubMed1999

Effectiveness of immunosuppressive therapy in older patients with aplastic anemia. European Group for Blood and Marrow Transplantation Severe Aplastic Anaemia Working Party.

BACKGROUND: Immunosuppressive therapy has been used for successful treatment of severe aplastic anemia, but little information is available on outcome in older patients. OBJECTIVE: To evaluate outcome in patients older than 50 years of age who received immunosuppressive therapy for aplastic anemia. DESIGN: Retrospective cohort study. SETTING: 56 centers of the European Group for Blood and Marrow Transplantation (EBMT). PATIENTS: 810 patients with aplastic anemia reported between 1974 and 1997. Patients were evaluated according to age group: 60 years of age or older (n = 127), 50 to 59 years of age (n = 115), and 20 to 49 years of age (n = 568; reference group). INTERVENTION: Antilymphocyte globulin, cyclosporine, or both. MEASUREMENTS: Survival, cause of death, response to treatment, relapse rate, and risk for late complications were analyzed in all patients and by age group. RESULTS: The 5-year survival rate was 57% (95% CI, 46% to 66%) in patients 50 to 59 years of age and 50% (CI, 39% to 60%) in patients 60 years of age or older compared with 72% (CI, 68% to 76%) in patients younger than 50 years of age (P < 0.001). Response to therapy, relapse rate, and risk for clonal complications were similar in all three age groups (P > 0.2). Age was significantly associated with an increased risk for death (relative risk compared with patients 20 to 49 years of age, 1.80 [CI, 1.29 to 2.52] for patients 50 to 59 years of age and 2.57 [CI, 1.87 to 3.53] for patients > or = 60 years of age), mainly because of bleeding or infection (P = 0.02). Response to immunosuppressive therapy in all patients at 12 months was 62% (CI, 58% to 66%); no difference was seen among the age groups in multivariate analysis (P > 0.2). Sixty-six of the 379 responding patients (17%) subsequently had relapse. The risk for clonal disorders at 10 years was 20% (CI, 15% to 27%). CONCLUSIONS: Response to immunosuppression in aplastic anemia is independent of age, but treatment is associated with increased mortality in older patients.

Adult↗
PubMed1999

Web PCR.

Explore the source record for details and available documents.

DNA Primers↗
PubMed1999

Liposomal amphotericin (AmBisome) in the prophylaxis of fungal infections in neutropenic patients: a randomised, double-blind, placebo-controlled study.

Liposomal amphotericin (AmBisome) 2 mg/kg three times weekly was compared with placebo as prophylaxis against fungal infection in patients undergoing chemotherapy or bone marrow transplantation (BMT) for haematological malignancies. Prophylaxis began on day 1 of chemotherapy and continued until neutrophils regenerated or infection was suspected. Of 161 evaluable patients, 74 received AmBisome and 87 received placebo. Proven fungal infections developed in no patients on AmBisome and in three on placebo (3.4%) (P = NS). Suspected fungal infections requiring intervention with systemic antifungal therapy (usually amphotericin B) occurred in 31 patients on AmBisome (42%) and in 40 on placebo (46%) (P = NS). Suspected deep-seated infections developed in 21 (28.3%) and 31 (35.6%) patients, respectively (P = NS). Time to develop a suspected or proven deep-seated infection showed a trend in favour of AmBisome (P = 0.11). Fifty patients had fungal colonisation (48 with Candida spp, two with Aspergillus spp) of at least one body site during prophylaxis; 15 patients while receiving AmBisome (20%) and 35 while on placebo (40%) (P < 0.01). Time to colonisation was significantly delayed in the group receiving AmBisome (P < 0.05). Treatment-related toxicity was modest and no additional toxicity was observed in patients receiving AmBisome. AmBisome 2 mg/kg three times weekly is safe and reduces fungal colonisation in patients receiving intensive chemotherapy or BMT. However, despite encouraging trends, prophylactic AmBisome did not lead to a significant reduction in fungal infection or in requirement for systemic antifungal therapy.

Adult↗
PubMed1998

Identification of Mexican Leishmania species by analysis of PCR amplified DNA.

Leishmania parasites isolated into culture from patients with LCL or DCL from four different Mexican states were characterised using polymerase chain reaction (PCR), hybridisation with specific probes, and isoenzymes. PCR of the parasites showed that 10 of 11 of those isolates were members of the mexicana complex. This was confirmed in seven cases by isoenzymes. Restriction enzyme digests of PCR products of Mexican isolates showed the isolates to be different from the L.(L.) mexicana reference strain BEL21. Two (C2 and AM) of the isolates were shown to be a possible mixed infection between mexicana and braziliensis complex members. With a second set of samples from different patients from Campeche state, PCR of 14 biopsies indicated the presence of braziliensis complex members in six of the samples. The results showed that most of our isolates of Leishmania which come from the states of Tabasco and Veracruz are members of the Leishmania mexicana complex, but they seem to be different from the L.(L.) mexicana BEL21 reference strain. By hybridisation most of the biopsies (seven out of 14) from Campeche belong to the L. braziliensis complex and two out of 14 to L. mexicana complex and three out of 14 hybridised with both complexes, and two biopsies were negative. In Campeche, which is very close to Tabasco state and has border with Guatemala, we found members of the L. mexicana and L. braziliensis complexes.

Animals↗
PubMed1998

Correlation of platelet Fc gammaRIIA polymorphism in refractory idiopathic (immune) thrombocytopenic purpura.

Fc gammaRIIA, a low affinity receptor for IgG, is a polymorphic molecule: Fc gammaRIIA-HH131, Fc gammaRIIA-HR131 and Fc gammaRIIA-RR131. This polymorphism influences the efficiency of the receptor to bind with IgG2. Recent reports on altered distribution amongst individuals with heparin-induced thrombocytopenia (HIT) prompted us to examine the Fc gammaRIIA polymorphism in a cohort of patients with refractory idiopathic (immune) thrombocytopenic purpura (ITP), in whom severe disease had required them to undergo splenectomy. 29 post splenectomy ITP individuals and 61 normal controls were investigated. Polymerase chain reaction (PCR) and a Southern blotting technique were used to determine the Fc gammaRII polymorphism. Although the distribution of the allotypes of Fc gammaRIIA in the control population was similar to that found in other European studies of Caucasian populations (15 (25%) HH131; 35 (57%) HR131; 11 (18%) RR131), the patient group was skewed towards the RR131 allotype which has least efficiency for IgG2 binding (3 (10%) HH131; 12 (42%) HR131; 14 (48%) RR131; P<0.005). These findings suggest that Fc gammaRIIA polymorphisms may be implicated in the pathophysiology of ITP or may be responsible for modulating the immune response in this heterogeneous autoimmune disease.

Adolescent↗
PubMed1998

Myb-related Schizosaccharomyces pombe cdc5p is structurally and functionally conserved in eukaryotes.

Schizosaccharomyces pombe cdc5p is a Myb-related protein that is essential for G2/M progression. To explore the structural and functional conservation of Cdc5 throughout evolution, we isolated Cdc5-related genes and cDNAs from Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila melanogaster, and Homo sapiens. Supporting the notion that these Cdc5 gene family members are functionally homologous to S. pombe cdc5(+), human and fly Cdc5 cDNAs are capable of complementing the temperature-sensitive lethality of the S. pombe cdc5-120 mutant. Furthermore, S. cerevisiae CEF1 (S. cerevisiae homolog of cdc5(+)), like S. pombe cdc5(+), is essential during G2/M. The location of the cdc5-120 mutation, as well as mutational analyses of Cef1p, indicate that the Myb repeats of cdc5p and Cef1p are important for their function in vivo. However, we found that unlike in c-Myb, single residue substitutions of glycines for hydrophobic residues within the Myb repeats of Cef1p, which are essential for maintaining structure of the Myb domain, did not impair Cef1p function in vivo. Rather, multiple W-to-G substitutions were required to inactivate Cef1p, and many of the substitution mutants were found to confer temperature sensitivity. Although it is possible that Cef1p acts as a transcriptional activator, we have demonstrated that Cef1p is not involved in transcriptional activation of a class of G2/M-regulated genes typified by SWI5. Collectively, these results suggest that Cdc5 family members participate in a novel pathway to regulate G2/M progression.

Amino Acid Sequence↗
PubMed1998

High frequency of donor chimerism after allogeneic transplantation of CD34+-selected peripheral blood cells.

Ex vivo T cell depletion of allogeneic grafts is associated with a high (up to 80%) rate of mixed chimerism (MC) posttransplantation. The number of transplanted progenitor cells is an important factor in achieving complete donor chimerism in the T cell depletion setting. Use of granulocyte colony-stimulating factor (G-CSF) peripheral blood allografts allows the administration of large numbers of CD34+ cells. We studied the chimeric status of 13 patients who received allogeneic CD34+-selected peripheral blood progenitor cell transplants (allo-PBPCTs/CD34+) from HLA-identical sibling donors. Patients were conditioned with cyclophosphamide (120 mg/kg) and total-body irradiation (13 Gy in four fractions). Apheresis products were T cell-depleted by the immunoadsorption avidin-biotin method. The median number of CD34+ and CD3+ cells infused was 2.8x10(6)/kg (range 1.9-8.6x10(6)/kg) and 0.4x10(6)/kg (range 0.3-1x10(6)/kg), respectively. Molecular analysis of the engraftment was performed using polymerase chain reaction (PCR) amplification of highly polymorphic short tandem repeat (PCR-STR) sequences in peripheral blood samples. MC was detected in two (15%) of 13 patients. These two patients relapsed at 8 and 10 months after transplant, respectively. The remaining 11 patients showed complete donor chimerism and were in clinical remission after a maximum follow-up period of 24 months (range 6-24 months). These results were compared with those obtained in 10 patients who were treated with T cell-depleted bone marrow transplantation by means of elutriation and who received the same conditioning treatment and similar amounts of CD3+ cells (median 0.45x10(6)/kg; not significant) but a lower number of CD34+ cells (median 0.8x10(6)/kg; p = 0.001). MC was documented in six of 10 patients (60%), which was significantly higher than in the allo-PBPCT/CD34+ group (p = 0.04). We conclude that a high frequency of complete donor chimerism is achieved in patients receiving allo-PBPCT/CD34+ and that this is most likely due to the high number of progenitor cells administered.

Adult↗