Cytomegalovirus (CMV) causes significant morbidity and mortality following allogeneic haemopoietic stem cell transplantation. A pre-emptive strategy for ganciclovir therapy is widely used, where ...treatment is commenced on finding positive evidence of CMV replication. Surveillance by PCR has increased the sensitivity for CMV detection, but it is not known whether this may detect cases with evidence of CMV DNAemia who have a low probability of CMV disease. We reviewed our experience of CMV infection and disease since introducing CMV surveillance by PCR. All 30 allografts received bedside leucodepleted CMV-negative blood products. Seven of 10 CMV-positive recipients of a CMV-positive graft developed CMV DNAemia, with three developing clinical disease requiring ganciclovir treatment. In contrast, of 11 low risk patients (CMV-negative recipients of CMV-negative grafts), six developed evidence of CMV DNAemia although only one had clinical evidence of CMV disease requiring ganciclovir. Transfusion records confirmed that four of these had received exclusively CMV-negative blood products. The aetiology of the CMV DNAemia in these cases is unclear. It is suggested that before commencing ganciclovir therapy, confirmatory CMV antigenaemia testing is carried out on samples which test positive for CMV DNA, unless there is high clinical suspicion of CMV disease.
Previous work has demonstrated that psychosocial morbidity may occur following bone marrow transplantation (BMT), but few prospective quantitative data are available, especially in adults. We have ...conducted a prospective psychological assessment of 36 patients accepted onto our BMT programme, of whom 31 proceeded to transplant. Patients were assessed shortly before admission for BMT and again at about 4 and 8 months after the procedure, using the following tools: Hospital Anxiety and Depression Scale (HAD), Social Adjustment Scale-Self Report and the Present State Examination (PSE). A 54% incidence of psychosocial morbidity (as assessed by either an abnormal HAD or PSE result) was found among those cases assessed both before and at least once after BMT. Significant psychosocial morbidity was still present 6-9 months following BMT. Cases scoring abnormally following BMT in general also scored abnormally before transplant, suggesting a predictive value of pre-BMT psychological assessment. Psychological morbidity was unrelated to the type of transplant. Patients with chronic myeloid leukaemia had a higher incidence of post-BMT psychosocial morbidity than patients with other diagnoses; it is suggested that this may be due to their lack of previous experience of intensive haematological therapy. Psychological evaluation may help in identifying patients at risk of post-BMT psychosocial problems.
The effects of list composition and word frequency on cued recall, associative recognition, and item recognition were examined in three experiments. For pure-frequency lists, cued recall and ...associative recognition show better performance on common high-frequency (HF) words than on rare low-frequency (LF) words. Item recognition, however, shows an advantage for LF words. In mixed lists, consisting of half HF and half LF words, the HF advantage in cued recall disappeared; however, the word frequency effects in item and associative recognition were unchanged. These results are inconsistent with explanations based on differential attention or co-rehearsal of HF and LF words. However, the results are consistent with list strength results which show that recognition is insensitive to strength-based list composition, but that recall is sensitive to list composition.
Background. Botulinum toxin types A and B can improve the appearance of facial wrinkles. Differences in the time until onset and the degree of diffusion have been observed anecdotally, but no direct ...comparative studies have been done.
Objective. To compare the rate of onset and the radius of diffusion of botulinum toxin types A and B in the rhytides of the forehead.
Methods. Adults with symmetrical moderate to severe forehead wrinkles at full contracture received botulinum toxin type A (BOTOX; 5 U) on one side of the forehead and type B (MYOBLOC; 500 U) on the other side. Photographs taken at rest and full frontalis contracture were analyzed by computer, and a time‐lapse motion picture was created. Radius of diffusion and time until full effect were measured.
Results. Botulinum toxin type B had a slightly faster onset of action than type A. All patients responded to type B quickly, whereas some had a delayed response to type A. A greater radius of diffusion was consistently observed with botulinum toxin type B, as measured by the greater area of wrinkle reduction at the doses used.
Conclusions. In this comparative study of patients with symmetrical forehead wrinkles, botulinum toxin type B produced a greater area of diffusion and a more rapid onset of action than type A.
Interleukin-3 (IL-3) is a member of a family of growth factors, each of which supports the proliferation and development of hematopoietic precursors in culture. Although the biologic effects of the ...different hematopoietic growth factors have been well documented in different culture systems, it has only recently become possible to study the activities of these molecules in vivo. In comparison with the later acting hematopoietic growth factors granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor, IL-3 elicited a delayed and relatively modest leukocytosis when continuously infused intravenously in primates. The IL-3 infusion, however, greatly potentiated the responsiveness of the animal to subsequent administration of a low dose of GM-CSF. These results suggest that IL-3 expands an early cell population in vivo that subsequently requires the action of a later acting factor such as GM-CSF to complete its development. Optimal stimulation of hematopoiesis may be achieved with combinations of hematopoietic growth factors.
Human skin is believed to harbor a reservoir population of precursor melanocytes. It has been difficult to identify these putative cells experimentally, because they lack phenotypic features that ...define mature melanocytes. We have evaluated expression of the KIT tyrosine kinase receptor, which is critical for melanocyte development, as a possible marker of these cells. Sections of human skin were evaluated with single- and double-immunolabeling techniques. KIT-reactive dendritic cells were identified in the basal layer of the epithelia and were most numerous in the follicular infundibula and the rete ridges. These cells were located on the epithelial side of the basement membrane and lacked expression of cytokeratin and mast cell tryptase. The location of the KIT-reactive cells was distinctly different from that of Langerhans cells (identified with anti-CD1a) or Merkel cells (identified with CAM 5.2). Within the epidermis and upper follicular infundibulum the majority of the KIT-reactive dendritic cells also coexpressed TRP-1, a marker present in differentiated melanocytes. In the deeper follicular regions, the coexpression of TRP-1 in the KIT-reactive cells was absent. Throughout the epidermis and follicle, however, the KIT-reactive cells coexpressed BCL-2, a marker known to be increased in melanocytes. Thus, KIT expression reveals a population of intraepithelial cells that have immunophenotypic characteristics of mature melanocytes within the upper epithelial regions, but lack the differentiated Melanocytic phenotype within the deeper follicular regions. We propose that these KIT(+), BCL-2(+), and TRP-1(−) cells constitute a precursor melanocyte reservoir of human skin.
Ballistic-neutralized chamber transport of intense heavy ion beams Rose, D.V; Welch, D.R; Oliver, B.V ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2001, Letnik:
464, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Two-dimensional particle-in-cell simulations of intense heavy ion beams propagating in an inertial confinement fusion (ICF) reactor chamber are presented. The ballistic-neutralized transport scheme ...studied uses
4
GeV
Pb
+1 ion beams injected into a low-density, gas-filled reactor chamber and the beam is ballistically focused onto an ICF target before entering the chamber. Charge and current neutralization of the beam is provided by the low-density background gas. The ballistic-neutralized simulations include stripping of the beam ions as the beam traverses the chamber as well as ionization of the background plasma. In addition, a series of simulations are presented that explore the charge and current neutralization of the ion beam in an evacuated chamber. For this vacuum transport mode, neutralizing electrons are only drawn from sources near the chamber entrance.
Antisense oligodeoxynucleotides targeted to bcr-abl are potential ex vivo purging agents for use with autologous bone marrow transplantation in the treatment of chronic myeloid leukemia (CIVIL). We ...investigated, in a cell-free system, the activity and nuclease resistance of phosphodiester, phosphorothioate, chimeric methylphosphonate/phosphodiester, and chimeric methylphosphonate/phosphorothioate antisense octadecamers directed against either b2a2 or b3a2 bcr-abl breakpoint RNAs. Certain chimeric compounds were shown to possess targeted activity broadly equal to the parent phosphodiester or phosphorothioate forms and greater resistance to the nucleases present in cell extracts. Selected chimeric structures were compared with phosphodiester and phosphorothioate analogues for antisense activity in human CML cells containing either b2a2 or b3a2 bcr-abl breakpoint mRNAs. We present results showing that all four structures can suppress bcr-abl mRNA level in vivo. The rank of in vivo activity is chimeric methylphosphonate/phosphodiester ≥ phosphodiester > phosphorothioate > methylphosphonate/phosphorothioate. We show that b2a2 breakpoint RNAs can be more effectively targeted than b3a2 sequence RNAs both in vitro and in vivo and suggest that RNA secondary structure may be a possible explanation for this phenomenon.
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