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Background and Purpose: Head down tilt 15° (HDT15°), applied before recanalization, increases collateral flow and improves outcome in experimental ischemic stroke. For its simplicity and low cost, HDT15° holds considerable potential to be developed as an emergency treatment of acute stroke in the prehospital setting, where hemorrhagic stroke is the major mimic of ischemic stroke. In this study, we assessed safety of HDT15° in the acute phase of experimental intracerebral hemorrhage., Methods: Intracerebral hemorrhage was produced by stereotaxic injection of collagenase in Wistar rats. A randomized noninferiority trial design was used to assign rats to HDT15° or flat position (n = 64). HDT15° was applied for 1 h during the time window of hematoma expansion. The primary outcome was hematoma volume at 24 h. Secondary outcomes were mass effect, mortality, and functional deficit in the main study and acute changes of intracranial pressure, hematoma growth, and cardiorespiratory parameters in separate sets of randomized animals (n = 32)., Results: HDT15° achieved the specified criteria of noninferiority for hematoma volume at 24 h. Mass effect, mortality, and functional deficit at 24 h showed no difference in the two groups. HDT15° induced a mild increase in intracranial pressure with respect to the pretreatment values (+2.91 ± 1.76 mmHg). HDT15° had a neutral effect on MRI-based analysis of hematoma growth and cardiorespiratory parameters., Conclusions: Application of HDT15° in the hyperacute phase of experimental intracerebral hemorrhage does not worsen early outcome. Further research is needed to implement HDT15° as an emergency collateral therapeutic for acute stroke., (© 2020 European Academy of Neurology.)

Background: Granulocyte-macrophage-colony stimulating factor (GM-CSF) administration stimulates the proliferation of hemopoietic progenitors. Shortly (48-96 hours) after its discontinuation, feedback phenomena occur and the progenitor proliferation rate drops below baseline levels. As the quiescence of hyperplastic bone marrow suggests that hemopoietic cells may be refractory to the toxic effects of cytostatic drugs, the decision was made to test the hypothesis that GM-CSF given before chemotherapy may be myeloprotective., Methods: Fifty-six patients with newly diagnosed Stage II-IV Hodgkin disease, ages 18-77 years, were randomized to receive GM-CSF (5 microg/kg subcutaneously) or placebo from Day 7 to Day 4 before each chemotherapy administration (6 cycles of a hybrid of mechlorethamine, vincristine, procarbazine, and prednisone with doxorubicin, bleomycin, vinblastine, and dacarbazine). The treatment was considered a success if the delivery rate of chemotherapy was >90% after 3 cycles and >80% after 6 cycles., Results: Thirty patients received GM-CSF and 26 placebo. The dose intensity (85.2% vs. 79.6%) and the overall success in terms of delivery rate (56.7% vs. 50%) were higher in the GM-CSF group, although these differences were not statistically significant. The neutrophil nadirs were higher in the GM-CSF group during the first three cycles and subsequently similar in both groups., Conclusions: No significant differences in terms of myelotoxicity or drug delivery were observed between the two treatment arms. Although the myeloprotective effect of the prechemotherapy administration of GM-CSF seems to be minimal, the data indicate a safe timing between GM-CSF discontinuation and further chemotherapy. Because cumulative myelotoxicity has been observed with other growth factors, given in the interval between the chemotherapy cycles, this may be relevant to the planning of rapid cycling., (Copyright 2000 American Cancer Society.)

Background: To study the correlation of environmental exposure to potentially mutagenic agents and the clinicopathologic picture in acute myeloid leukemia (AML), clinical features, morphologic characteristics, immunophenotype, and cytogenetics were studied in 59 patients with newly diagnosed AML., Methods: Based on interviews on occupational hazards and hobbies showing prolonged contact with pesticides (18 patients) and organic solvents (7 patients), 25 patients were categorized as "exposed". Thirty-four patients were categorized as "unexposed,", based on anamnestic findings., Results: Light microscopic studies showed myelodysplasia involving multiple cell lineages in all assessable patients with professional exposure to pesticides and organic solvents, whereas morphologic aberrations of the non-blast cell population were confined to a minority of cells in unexposed patients. These findings were confirmed by electron microscopic studies in 31 patients. Immunologic analysis showed the presence of a minor megakaryoblastic component in six exposed patients and showed positive findings for the CD34 stem cell marker in 85% of exposed patients, a figure significantly higher as compared with that for unexposed subjects. Cytogenetic studies confirmed the frequent occurrence of 5q and/or 7q aberrations in patients occupationally exposed (10 of 25 cases). Other recurring chromosome aberrations in the exposed group were 17p-, trisomy 11q, and translocation of 16q, 6p, 7p, and 11p, whereas the classic AML-specific translocations (i.e., t[15;17]; t[8;21]) were detected only in unexposed subjects. Conventional chemotherapy achieved complete remission in 1 of 19 exposed patients, as opposed to 14 of 29 unexposed patients, with a median survival of 2 months in the former group and 8 months in the latter., Conclusions: Taken together, these findings document that AML in patients professionally exposed to toxic substances may represent a distinct cytogenetic and clinicopathologic entity. The clinicobiologic characteristics in these exposed patients are similar to the features of AML arising in patients with prior chemotherapy for another tumor, thus suggesting that similar transformation pathways may underlie leukemogenesis induced by cytotoxic drugs and by environmental exposure to some pesticides or organic solvents.

A case of acute myelomonocytic leukemia terminating in histiocytic medullary reticulosis is reported. The evolution of a single cellular clone presenting with progressive change of the morphological features of the leukemic cells towards more anaplastic elements endowed with prominent phagocytic properties is suggested on the basis of both cytochemical and chromosomal data. The histiocytic nature of the malignant proliferating cells and platelet phagocytosis has been confirmed by electron microscopic investigation. The main pathogenetic explanations of the evolutionary patterns of the disease are discussed with relation to: a) involvement of a common stem cell giving rise to different proliferative patterns of cells in a multiphasic sequence; b) release of dysplastic platelets and defective erythrocytes with massive sequestration by histioid phagocytic cells; and c) coexistence of two different disorders.