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91.
Bodine  DM; Seidel  NE; Gale  MS; Nienhuis  AW; Orlic  D 《Blood》1994,84(5):1482-1491
Cytokine-mobilized peripheral blood cells have been shown to participate in hematopoietic recovery after bone marrow (BM) transplantation, and are proposed to be useful targets for retrovirus- mediated gene transfer protocols. We treated mice with granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF) to mobilize hematopoietic progenitor cells into the peripheral blood. These cells were analyzed for the number and frequency of pluripotent hematopoietic stem cells (PHSC). We found that splenectomized animals treated for 5 days with G-CSF and SCF showed a threefold increase in the absolute number of PHSC over normal mice. The number of peripheral- blood PHSC increased 250-fold from 29 per untreated mouse to 7,200 in peripheral-blood PHSC in splenectomized animals treated for 5 days with G-CSF and SCF. Peripheral blood PHSC mobilized by treatment with G-CSF and SCF were analyzed for their ability to be transduced by retroviral vectors. Peripheral-blood PHSC from splenectomized animals G-CSF and SCF were transduced with a recombinant retrovirus containing the human MDR-1 gene. The frequency of gene transfer into peripheral blood PHSC from animals treated for 5 and 7 days was two-fold and threefold higher than gene transfer into PHSC from the BM of 5-fluorouracil-treated mice (P < .01). We conclude that peripheral blood stem cells mobilized by treatment with G-CSF and SCF are excellent targets for retrovirus- mediated gene transfer.  相似文献   
92.
LeMarbre  P; Rinehart  JJ; Kay  NE; Vesella  R; Jacob  HS 《Blood》1981,58(5):994-999
The mononuclear phagocyte is well established as an in vitro cytotoxic effector cell for certain human tumors. The mechanism(s) for this action remains unclear. Increased levels of lysozyme, a cationic enzyme synthesized in large amounts by mononuclear phagocytes, are associated with increased resistance to transplantable animal tumors. In this study, we provide evidence that human lysozyme, isolated from the urine of leukemic patients, has marked potentiating effects on human monocyte- tumor-cell cytocidal activity. In addition, lysozyme-exposed monocytes incorporate increased quantities of leucine, suggesting that monocytes are capable of amplifying their own metabolic activation by secreting an endogenous constituent. Tri-N-acetyl-glucosamine, a competitive inhibitor for the active site of lysozyme, inhibits cytocidal activity. Conversely, protamine, an extraneous albeit similarly positively charged molecule, increases monocyte-mediated tumor cytotoxicity; this protamine effect is negated by heparin. We conclude that lysozyme, at least partially by its positive charge, is capable of enhancing in vitro monocyte tumor cell cytotoxicity; its in vivo secretion may potentiate monocyte-tumor-cell interaction.  相似文献   
93.
BACKGROUND AND OBJECTIVE: Based on our preliminary experience, we have further evaluated the capacity of the paclitaxel/epirubicin combination (at the dose of 175 and 90 mg/m(2), respectively) plus G-CSF to mobilize hematopoietic progenitors into the circulation. DESIGN AND METHODS: The study was conducted in a homogeneous cohort of 25 stage IV breast cancer patients showing response to three cycles of the same chemotherapy regimen and who were included in a high-dose chemotherapy program. RESULTS: In most cases (68%) more than 5_10(6) CD34+ cells/kg b.w. (the threshold fixed in our study) were collected by a single leukapheresis, 28% and 4% of patients requiring 2 and 3 procedures, respectively. Based on the CD34+ cell count in the peripheral blood, most of the leukaphereses (53%) were performed on day 11 after chemotherapy. More than 50 CD34+ cells/mL along with a preleukapheresis WBC count between 10 and 20_10(9)/L predicted that only a single harvest would be required in 100% of cases. The evaluation of the clonogenic potential of collected cells showed that a large number of committed colony-forming cells (CFCs) and more primitive long-term culture-initiating cell (LTC-IC) hematopoietic progenitors were present in 20 harvests studied. INTERPRETATION AND CONCLUSIONS: These data demonstrate that the epirubicin/paclitaxel combination followed by G-CSF, besides being a very active regimen in MBC, is effective in releasing large amounts of progenitor cells into the circulation which can then be safely employed to support myeloablative regimens.  相似文献   
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Orbital reconstruction in cases of trauma is usually performed using the unaffected side orbital volume as a reference, but this measurement does not fully consider the anatomical characteristics of orbital surfaces.We propose a novel procedure based on the registration of 3D orbital segmented surfaces. Reconstructed orbits from 20 patients and healthy orbits from 13 control subjects were segmented from the post-operative CT-scans. The 3D orbital model from the unaffected orbit was “mirrored” according to the sagittal plane and superimposed onto the reconstructed one, with calculation of volumes, asymmetry index and point-to-point RMS (root mean square) distances. Inter- and intra-observer errors were tested through Bland–Altman plot. Differences in volume, asymmetry index and RMS value between the control group and the treated patients were assessed through two-way ANOVA and Student's t-test (p < 0.05).According to Bland–Altman test, intra- and inter-operator repeatability was respectively 87% and 89%. No significant differences in volume or asymmetry index between the control group and the treated patients were observed (p > 0.05), but the RMS value was significantly larger in the latter ones (on average, 0.90 ± 0.26 mm vs. 0.67 ± 0.17 mm, p < 0.05).Results show that the reconstructed orbits present a morphologically different surface from the unaffected ones.  相似文献   
98.

Purpose

Surgical reconstruction of zygomatic bones in cases of traumatic injuries is a frequent event: assessment of symmetry is mandatory for a correct restoration of zygomatic shape, but the literature is discordant about its quantification. The purpose of this study is to show a novel method for assessing symmetry of zygomatic bone through mirroring of 3D models segmented on CT-scan.

Materials and methods

A total of 100 patients (50 male and 50 female), divided into two age groups (18–49 years and 50–92 years) were selected from the computed tomography (CT) scan database of a hospital in northern Italy. Zygomatic bones from each patient were segmented, and the left bone was automatically mirrored and registered on the right one according to the least point-to-point distance between the two surfaces. The mean and root mean square (RMS) distance between the two models was then calculated. Statistically significant differences according to sex and age groups were assessed through two-way analysis of variance (p < 0.05). In addition, the effect size of differences was calculated.

Results

The method proved to be repeatable, with inter- and intraoperator errors lower than 5%. Overall, mean and RMS point-to-point distances were respectively 0.01 mm and 0.84 mm, without statistically significant differences according to sex or age (p > 0.05), and with negligible effect size.

Conclusion

This study provides an innovative method for assessing the symmetry of the zygomatic bone based on surface analysis. Results may provide useful indications for the reconstruction of zygomatic bones in maxillofacial surgery.  相似文献   
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PURPOSE: To evaluate the incidence of thyroid disorders and dose distribution to the thyroid in patients treated with radiotherapy for head-and-neck carcinomas. METHODS AND MATERIALS: A retrospective evaluation of data from 73 patients treated for head-and-neck cancers in our department was performed. Thyroid function was evaluated mainly by the measurement of thyrotropin (thyroid stimulating hormone [TSH]). A retrospective analysis of treatment plans was performed for 57 patients. Percentages of thyroid glandular volume absorbing 10, 30, and 50 Gy (V10, V30, and V50 respectively) were considered for statistical analysis. RESULTS: A majority of patients (61%) had a normal thyroid function whereas 19 patients (26%) had hypothyroidism. Mean thyroid volume was 30.39 cc. Point 3 (located at isthmus) absorbed lower doses compared with other points (p < 0.0001). Median values of V10, V30, and V50 were 92% (range, 57-100%), 75% (range, 28.5-100%), and 35% (range, 3-83%) respectively. Gender was associated with toxicity (presence of any kind of thyroid disorders) (p < 0.05), with females displaying higher levels of TSHr (relative TSH = patient's value/maximum value of the laboratory range) (p = 0.0005) and smaller thyroid volume (p = 0.0012) compared with male population. TSHr values were associated with thyroid volume, and the presence of midline shielding block in the anterior field was associated with relative free thyroxine (FT4r = patient's value/maximum value of the laboratory range) values. CONCLUSIONS: Gender and thyroid volume seem to play an important role in the occurrence of thyroid toxicity, but further studies on dose-effect relationship for radiotherapy-induced thyroid toxicity are needed.  相似文献   
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