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1.
Nat Commun ; 13(1): 7390, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36450728

ABSTRACT

Mercury's southern inner magnetosphere is an unexplored region as it was not observed by earlier space missions. In October 2021, BepiColombo mission has passed through this region during its first Mercury flyby. Here, we describe the observations of SERENA ion sensors nearby and inside Mercury's magnetosphere. An intermittent high-energy signal, possibly due to an interplanetary magnetic flux rope, has been observed downstream Mercury, together with low energy solar wind. Low energy ions, possibly due to satellite outgassing, were detected outside the magnetosphere. The dayside magnetopause and bow-shock crossing were much closer to the planet than expected, signature of a highly eroded magnetosphere. Different ion populations have been observed inside the magnetosphere, like low latitude boundary layer at magnetopause inbound and partial ring current at dawn close to the planet. These observations are important for understanding the weak magnetosphere behavior so close to the Sun, revealing details never reached before.

2.
Space Sci Rev ; 217(1): 11, 2021.
Article in English | MEDLINE | ID: mdl-33487762

ABSTRACT

The ESA-JAXA BepiColombo mission to Mercury will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric particle dynamics at Mercury as well as their interactions with solar wind, solar radiation, and interplanetary dust. The particle instrument suite SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) is flying in space on-board the BepiColombo Mercury Planetary Orbiter (MPO) and is the only instrument for ion and neutral particle detection aboard the MPO. It comprises four independent sensors: ELENA for neutral particle flow detection, Strofio for neutral gas detection, PICAM for planetary ions observations, and MIPA, mostly for solar wind ion measurements. SERENA is managed by a System Control Unit located inside the ELENA box. In the present paper the scientific goals of this suite are described, and then the four units are detailed, as well as their major features and calibration results. Finally, the SERENA operational activities are shown during the orbital path around Mercury, with also some reference to the activities planned during the long cruise phase.

4.
Bone Marrow Transplant ; 27(2): 145-53, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11281383

ABSTRACT

In an attempt to reduce the high relapse rate associated with ABMT, five children with high-risk first CR and 19 in second or subsequent CR lacking matched family allogeneic donors underwent ABMT with chemopurged bone marrow utilizing verapamil (VPL), vincristine, and VP-16. Patients were conditioned with TBI, VPL bolus and infusion with VP-16 and cyclophosphamide. The first cohort of patients (n = 4) received only cyclosporin A (CsA). The second cohort (n = 7) received CsA and alpha interferon (total = 11 with post-transplant immunotherapy alone.) The third cohort (n = 13) received CsA and six alternating cycles of alphaIFN and chemotherapy and six additional cycles of chemotherapy (vincristine, VP-16, Ara-C, prednisone) followed by G-CSF (post-transplant immune chemotherapy (PTIC)). The 2-year DFS is 42+/-10% (90% confidence interval (CI) is 26.5-58.5%) and 2-year overall survival is 54+/-10% (90% CI is 37.5-70.5%). Furthermore, patients receiving PTIC (n = 13) vs immunotherapy alone (CsA+/-aIFN) (n = 11) had a substantially better 2 year DFS and OS: 69+/-13% vs 13+/-12% and 85+/-10% vs 25+/-15% (P = 0.008 and P = 0.06, respectively). These results suggest that the use of ABMT with chemopurging, combined with PTIC is well tolerated and may be an alternative new approach in the treatment of a subset of children with high-risk first CR or > or = second CR ALL who lack closely matched family-related allogeneic donors.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Bone Marrow Purging , Bone Marrow Transplantation , Graft vs Leukemia Effect , Immunotherapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Adolescent , Adult , Child , Child, Preschool , Combined Modality Therapy , Cyclosporine/administration & dosage , Female , Granulocyte Colony-Stimulating Factor/administration & dosage , Humans , Immunosuppressive Agents/administration & dosage , Male , Transplantation, Autologous , Treatment Outcome
5.
Nature ; 404(6774): 159-61, 2000 Mar 09.
Article in English | MEDLINE | ID: mdl-10724161

ABSTRACT

The composition and evolutionary history of Mercury's crust are not well determined. The planet as a whole has been predicted to have a refractory, anhydrous composition: rich in Ca, Al, Mg and Fe, but poor in Na, K, OH, and S. Its atmosphere is believed to be derived in large part from the surface materials. A combination of effects that include impact vaporization (from infalling material), volatile evaporation, photon-stimulated desorption and sputtering releases material from the surface to form the atmosphere. Sodium and potassium have already been observed in Mercury's atmosphere, with abundances that require a volatile-rich crust. The sodium probably results from photon-stimulated desorption, and has a temperature of 1,500 K (ref. 10). Here we report the discovery of calcium in the atmosphere near Mercury's poles. The column density is very low and the temperature is apparently very high (12,000 K). The localized distribution and high temperature, if confirmed, suggest that the atmospheric calcium may arise from surface sputtering by ions, which enter Mercury's auroral zone. The low abundance of atmospheric Ca may indicate that the regolith is rarefied in calcium.


Subject(s)
Calcium/analysis , Extraterrestrial Environment , Mercury, Planet , Atmosphere , Spectrum Analysis
6.
Bone Marrow Transplant ; 19(3): 197-204, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9028545

ABSTRACT

Fifteen children 4 years of age or under (8-46 months), weight 7.8 to 17 kg, underwent 44 peripheral blood stem cell (PBSC) collections. Diagnoses included PNET/medulloblastoma (five), neuroblastoma (five), and others (five). PBSCs were collected following G-CSF/GM-CSF or chemotherapy plus G-CSF/GM-CSF mobilization. All PBSC collections were well tolerated. The average yield per collection was 6.80 x 10(8) mononuclear cells/kg (1.1-30 x 10(8)/kg) or 57.60 x 10(6) CD34+/kg (1.37 to 480 x 10(6)/kg). Eight patients underwent stem cell transplantation following myeloablative chemotherapy. Six of the eight children who received PBSC following myeloablative therapy also received autologous bone marrow (0.7 to 3.6 x 10(8) MNC/kg). One heavily pretreated patient experienced delayed hematologic reconstitution, while the remaining seven patients had a median ANC recovery to > 0.5 x 10(3)/microliter by day +10 (9-11 days) and platelets > 50 x 10(3)/microliter by day +15 (12-17 days). Seven patients received PBSCs following repetitive submyeloablative chemotherapy (ICE: ifosfamide 1.8 g/m2/day, etoposide 100 mg/m2/day x 5, carboplatin 400 mg/m2/day x 2) or other similar combination chemotherapy. Median days to recover ANC > or = 1 x 10(3)/microliter and platelets > or = 100 x 10(3)/microliter in children receiving ICE + PBSCs were 10 and 14 days, respectively, compared with 16 and 22 days in children receiving ICE + G-CSF in historical controls. In conclusion, collection and use of PBSCs to support either myeloablative chemotherapy or multicycle submyeloablative chemotherapy is well tolerated and may enhance hematological recovery in young children and infants.


Subject(s)
Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/pathology , Neoplasms/therapy , Blood Component Removal , Cell Separation , Child, Preschool , Humans , Infant , Treatment Outcome
7.
J Pediatr Nurs ; 11(6): 359-67, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8991336

ABSTRACT

Constructive, therapeutic play is an essential part of the care of children with long-term hospitalizations. The O'Connor theoretical framework supports the importance of play in ensuring the emotional, developmental, and physical health of children. The negative effects of long-term hospitalization are particularly evident for children who have undergone bone marrow transplants and must be kept in germ-free environment and isolation for extended periods of time. This article describes a successful play therapy program in a Bone Marrow Transplant Unit, using a play cabinet designed to provide readily available, sterilized toys that are appropriate for each of four age groups. Two cases are presented that show the efficacy of the use of the play cabinet in play therapy programs.


Subject(s)
Bone Marrow Transplantation/nursing , Bone Marrow Transplantation/psychology , Child, Hospitalized/psychology , Play Therapy/organization & administration , Child , Child Development , Child, Preschool , Female , Humans , Infant , Male , Models, Psychological , Pediatric Nursing , Play and Playthings
8.
Bone Marrow Transplant ; 18(1): 185-91, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8832013

ABSTRACT

Veno-occlusive disease (VOD) of the liver is an early complication of bone marrow transplantation (BMT). The initial event has been hypothesized to be an injury to the endothelial cells eventually resulting in post-sinusoidal obstruction and hepatic failure. The role of anticoagulants for the prevention of VOD is controversial. Continuous infusion of heparin has been reported to be effective in preventing VOD in adults undergoing myeloablative therapy and BMT. An unblinded, historical controlled study was carried out to assess the safety and efficacy of continuous infusion of low-dose heparin in prevention of VOD in children undergoing BMT following myeloablative therapy. Fifty consecutively BMT-treated children (10 months to 18 years 7 months) were enrolled into the study group and received continuous heparin infusion (100 units/kg/day) from the first day of the preparative regimen to day +30 or until discharge, whichever occurred earlier. These were compared with a control group of 70 patients who received BMT for a variety of disorders. Patient groups were similar with respect to primary diagnosis, age, sex, and baseline organ functions. Heparin was well-tolerated, with only minor grade I-II hemorrhagic episodes occurring in 28 patients (56%), compared to 50 patients in the control group (71%) (P = 0.184). Bleeding was significantly less following autologous BMT compared to allogeneic BMT (P < 0.05). VOD was diagnosed in five patients (10%) compared to 18 of 70 in the control group (25.7%) (P < 0.05). Analysis of risk factors demonstrated a significantly higher incidence of VOD in patients undergoing allogeneic BMT (matched related, mismatched related and matched unrelated), patients older than 15 years of age, and patients with advanced disease (> or = 2 CR). In summary, this phase II trial has demonstrated that continuous heparin infusion can be safely used prophylactically in children undergoing myeloablative therapy and BMT. The incidence of moderate and serious VOD was significantly less compared to historical controls. A future randomized, double-blinded, placebo-controlled phase III trial is, however, required to determine the efficacy of heparin in preventing VOD in children undergoing myeloablative therapy and BMT.


Subject(s)
Anticoagulants/therapeutic use , Bone Marrow Transplantation/adverse effects , Heparin/therapeutic use , Hepatic Veno-Occlusive Disease/prevention & control , Adolescent , Anticoagulants/administration & dosage , Anticoagulants/pharmacology , Child , Child, Preschool , Female , Hemorrhage/chemically induced , Heparin/administration & dosage , Heparin/pharmacology , Hepatic Veno-Occlusive Disease/epidemiology , Hepatic Veno-Occlusive Disease/etiology , Humans , Incidence , Infant , Infusions, Intravenous , Male , Prospective Studies , Risk Factors , Safety , Transplantation Conditioning/adverse effects , Treatment Outcome
9.
Science ; 252(5008): 974-5, 1991 May 17.
Article in English | MEDLINE | ID: mdl-17843230
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