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91.
Neonates, especially those of very low birthweight (VLBW), have an increased risk of nosocomial infections secondary to deficiencies in development. We previously demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) production and mRNA expression from stimulated neonatal mononuclear cells are significantly less than that from adult cells. Recombinant murine GM-CSF administration to neonatal rats has resulted in neutrophilia, increased neutrophil production, and increased survival of pups during experimental Staphylococcus aureus sepsis. In the present study, we sought to determine the safety and biologic response of recombinant human (rhu) GM-CSF in VLBW neonates. Twenty VLBW neonates (500 to 1,500 g), aged < 72 hours, were randomized to receive either placebo (n = 5) or rhuGM-CSF at 5.0 micrograms/kg once per day (n = 5), 5.0 micrograms/kg twice per day (n = 5), or 10 micrograms/kg once per day (n = 5) given via 2-hour intravenous infusion for 7 days. Complete blood counts, differential, and platelet counts were obtained, and tibial bone marrow aspirate was performed on day 8. Neutrophil C3bi receptor expression was measured at 0 and 24 hours. GM-CSF levels were measured by a sandwich enzyme-linked immunosorbent assay at 2, 4, 6, 12, and 24 hours after the first dose of rhuGM-CSF. At all doses, rhuGM-CSF was well tolerated, and there was no evidence of grade III or IV toxicity. Within 48 hours of administration, there was a significant increase in the circulating absolute neutrophil count (ANC) at 5.0 micrograms/kg twice per day and 10.0 micrograms/kg once per day, which continued for at least 24 hours after discontinuation of rhuGM-CSF. When the ANC was normalized for each patient's first ANC, there was a significant increase in the ANC on days 6 and 7 at each dose level. By day 7, all tested doses of rhuGM- CSF resulted in an increase in the absolute monocyte count (AMC) compared with placebo-treated neonates. In those receiving rhuGM-CSF 5.0 micrograms/kg twice per day, there was additionally a significant increase in the day 7 and 8 platelet count. Tibial bone marrow aspirates demonstrated a significant increase in the bone marrow neutrophil storage pool (BM NSP) at 5.0 micrograms/kg twice per day and 10.0 micrograms/kg once per day. Neutrophil C3bi receptor expression was significantly increased 24 hours after the first dose of rhuGM-CSF at 5.0 micrograms/kg once per day. The elimination half-life (T1/2) of rhuGM-CSF was 1.4 +/- 0.8 to 3.9 +/- 2.8 hours.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
92.
Thein  SL; Hesketh  C; Brown  JM; Anstey  AV; Weatherall  DJ 《Blood》1989,73(4):924-930
Two families, one of Anglo-Saxon-Dutch descent, and the other, West Indian black, have an atypical beta thalassemia characterized by an unusually high level of Hb A2 in the heterozygous state. Restriction endonuclease mapping showed a deletion of about 1.35 kilobase (kb) in the 5' region of the beta globin gene. Direct sequencing of a specific region of genomic DNA amplified by a new modification of the polymerase chain reaction defined the deletion to be 1,393 base pairs (bp) and to be the same in both families. The deletion extends from 485 bp 5' to the mRNA CAP site to the middle of the second intervening sequence. This deletion, together with three others previously described that remove the 5' end of the beta gene but leave the delta gene intact, are all associated with unusually high levels of Hb A2 in the heterozygous state.  相似文献   
93.
High-dose chemoradiotherapy conditioning regimens for autologous stem cell transplantation (ASCT) are generally held to give similar results in multiple myeloma (MM), but no specific comparative study has been published. We addressed this issue by comparing the main high-dose chemoradiotherapy regimens used in the Spanish Registry. Patient cohorts included 315 cases treated with 200 mg/m2 melphalan (MEL200), 127 patients with 140 mg/m2 melphalan plus total body irradiation (MEL140 + TBI) and 121 cases with 12 mg/kg busulphan plus 140 mg/m2 melphalan (BUMEL). After ASCT, granulocyte and platelet recovery time was similar in all conditioning groups. There were no differences in transplant-related mortality. All regimens yielded a similar response in reference to pre-ASCT MM status, although BUMEL produced a slightly better overall response when compared with the other regimens (97% vs. 89% and 92%, P = 0.003). The 5-year overall survival (OS) with BUMEL was 47% [95% confidence interval (CI) 26-68] compared with 43% (CI 31-54) for MEL140 + TBI and 37% (CI: 18-56) for MEL200. The median survival for the BUMEL group was 64 months compared with 45 and 37 months for the MEL200 and MEL140 + TBI groups respectively. These differences were non-significant (P = 0.2). The median event-free survival (EFS) was better for BUMEL (32 months) than for MEL200 (22 months) or for MEL140 + TBI (20 months). The differences in EFS between BUMEL and the other conditioning regimens reached statistical significance (P = 0.01). Nevertheless, the adjusted multivariate analysis for OS and EFS revealed that the conditioning regimens had no independent prognostic value. We concluded that three different conditioning regimens, commonly used for ASCT in MM, have a similar antimyeloma effect. However, the trend for better results observed in our series with BUMEL requires a prospective trial.  相似文献   
94.
Although the life-threatening cytomegalovirus (CMV) disease is a well known complication following allogeneic hematopoietic stem cell transplantation (HSCT), it has been considered infrequent after autologous peripheral blood stem cell transplantation (PBSCT). On the other hand, the massive involvement of the gastrointestinal (GI) tract as the primary site of fatal CMV disease is particularly rare after autologous PBSCT. We present the case of a woman who suffered from CMV disease after high-dose busulphan/melphalan/thiotepa (BuMelTT) and autologous PBSCT. The primary site of infection was the GI tract, which was extensively affected. During the fifth week post-transplant the patient started with epigastralgia, diarrhea, fever, GI bleeding, and thrombocytopenia, and she died on day +52. Another case of fatal CMV disease among the few patients treated with BuMelTT has been recently reported, which suggests that the immunodeficiency associated with that regimen can be as intense as that occurring after allogeneic BMT.  相似文献   
95.
Ganesan  TS; Min  GL; Goldman  JM; Young  BD 《Blood》1987,70(3):873-876
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone.  相似文献   
96.
97.
Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo.  相似文献   
98.
99.
Keratinocyte migration is a mandatory aspect of wound healing. We have previously shown that amniotic membrane (AM) applied to chronic wounds assists healing through a process resulting in the overexpression of c‐Jun at the wound's leading edge. We have also demonstrated that AM modifies the genetic programme induced by transforming growth factor‐ß (TGF‐ß) in chronic wounds. Here we used a scratch assay of mink lung epithelial cells (Mv1Lu) and a spontaneously immortalized human keratinocyte cell line (HaCaT) cells to examine the influence of AM application on the underlying signalling during scratch closure. AM application induced c‐Jun phosphorylation at the leading edge of scratch wounds in a process dependent on MAPK and JNK signalling. Strikingly, when the TGF‐ß‐dependent Smad‐activation inhibitor SB431542 was used together with AM, migration improvement was partially restrained, whereas the addition of TGF‐ß had a synergistic effect on the AM‐induced cell migration. Moreover, antagonizing TGF‐ß with specific antibodies in both cell lines or knocking out TGF‐ß receptors in Mv1Lu cells had similar effects on cell migration as using SB431542. Furthermore, we found that AM was able to attenuate TGF‐ß‐Smad signalling specifically at the migrating edge; AM treatment abated Smad2 and Smad3 nuclear localization in response to TGF‐ß in a process dependent on mitogen‐activated protein kinase kinase 1 (MEK1) activation but independent of EGF receptor or JNK activation. The involvement of Smad signalling on AM effects on HaCaT keratinocytes was further corroborated by overexpression of either Smad2 or Smad3 and the use of Smad phosphorylation‐specific inhibitors, revealing a differential influence on AM‐induced migration for each Smad. Thus, AM TGF‐ß‐Smad signalling abating is essential for optimal cell migration and wound closure.  相似文献   
100.
In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus.  相似文献   
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