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Biomedical subjects

A Rambaldi

Publications and source records attributed to A Rambaldi.

173 records · Page 10Linked to original sources

Organ-specific growth of a murine lymphoma of spontaneous origin in nude mice.

The MOC-25 tumour arose spontaneously in a female nude mouse and was established as a continuous line intraperitoneally in nude mice, where it reproduces the topological features of its origin, growing preferentially in the uterus, ovaries and liver. Karyotype analysis showed that MOC-25 cells are hyperdiploid. Tumorigenicity and malignant behaviour were studied by transplanting tumour cells into different sites in nude mice. The comparison of tumour take after i.p. and s.c. injections of scaled concentrations of MOC-25 cell suspension showed preferential growth in the peritoneum. Regardless of the route of implantation (s.c., i.v., i.p.), this tumour rapidly and preferentially disseminated to the liver, uterus, ovaries, spleen and bone marrow. No significant differences in tumour growth and metastatic behaviour were observed when MOC-25 was injected in ovariectomized nude mice or in male nude mice. Morphology studies using light and electron microscopy, immunophenotyping and molecular analysis indicated a B-lymphoid origin of the MOC-25 tumour.

Animals↗

Visceral leishmaniasis during pregnancy treated with meglumine antimoniate.

Data on the efficacy and safety of pentavalent antimony in the treatment of visceral leishmaniasis during pregnancy are scanty. A case of visceral leishmaniasis in a 39-year-old woman in the second trimester of pregnancy is reported here. The patient was hospitalized in poor condition with high fever and pancytopenia which had lasted for 6 weeks. A bone marrow aspirate revealed numerous amastigotes and serodiagnosis for Leishmania was positive at a high titer. The patient was successfully treated with meglumine antimoniate at a daily dose of 850 mg of antimony for 20 days. She delivered at term a healthy female baby who remains in good condition at 18 months of age. Thus a dose of 850 mg of antimony, which is lower than that presently recommended, seems to be effective and non toxic to the fetus when administered at the second trimester of pregnancy.

Adult↗

Immunological and genotypic analysis of human T gamma-lymphoproliferative disorders.

T gamma-lymphoproliferative disorders (T gamma-LPD) are rare diseases characterized by expansion of circulating elements with resemblance to large granular lymphocytes (LGL). We have studied 12 patients with T gamma-LPD. Morphological evaluation revealed 79-88% of LGL in non-adherent peripheral blood lymphocytes as assessed by light and electron microscopy. The most common features of the membrane phenotype included expression of T3, HNK-1 and AB8.28 (anti-Fc gamma); other surface markers of LGL (OKM1, B73.1, N901) were variably expressed or absent. Patients' LGL usually had little or no NK activity, with the exception of two patients who had values comparable to those of normal donors; in addition, cell preparations from all patients mediated antibody-dependent cellular cytotoxicity. The recent availability of the T cell receptor beta chain probes allowed us to investigate the lineage and the clonality of T gamma-LPD. Of the 12 patients analyzed, 10 displayed clonal rearrangements of T beta locus and expression of the T3 antigen, whereas the two remaining cases displayed a germ-line configuration of the T beta gene and no expression of the T3 antigen. We suggest that individual T gamma-LPD cases represent the clonal expansion of cells frozen at different stages of differentiation/activation within an individual hematopoietic LGL/NK lineage. These data suggest that either a subset of LGL or a particular step of differentiation may be related to the T cell lineage.

Antibody-Dependent Cell Cytotoxicity↗

A human acute lymphoblastic leukemia line with the T(4;11) translocation as a model of minimal residual disease in SCID mice.

This study describes a new human acute lymphoblastic leukemia (ALL) cell line (ALL-PO) with the t(4;11) translocation established in SCID mice. The ALL-PO line can be maintained by serial transplant in SCID mice with stable immunophenotypic, molecular and karyotypic features. After intravenous (i.v.) injection ALL-PO spread systemically involving the hematopoietic organs and the central nervous system (CNS) of all mice. The homing and the progression of the disease are evaluated by histological analysis and reverse-transcriptase polymerase chain reaction (RT-PCR) amplification of the t(4;11) translocation in the bone marrow, spleen and CNS of SCID mice at different times after engraftment. Occult leukemia was detectable by PCR in the bone marrow of SCID mice as early as three days after the i.v. injection of leukemic cells whereas the first signs of involvement of the spleen and CNS appeared after 14 days; after 24 days all the mice were euthanized because they were moribund and the bone marrow, spleen and CNS showed ample infiltration by leukemic cells. The sensitivity to conventional chemotherapy was tested in this model. ALL-PO in SCID mice did not respond to treatment with vincristine or idarubicin but cyclophosphamide (150 mg kg(-1) i.v., single injection) significantly increased the survival of the mice. The efficacy of such a treatment was more evident when cyclophosphamide was given in the early stages of the disease (detectable only by molecular analysis) but much less effective when the drug was administered when the disease could be detected by conventional histological analysis. The biological behavior and molecular characteristics of ALL-PO make it a good model for studying novel therapeutic strategies for a better control of minimal residual disease.

Animals↗

Interleukin-1 and glomerular mesangial cells.

Our previous in vitro study demonstrated that interleukin-1 (IL-1) stimulates gene expression and production of leukocyte chemotactic factors, colony-stimulating factors and interleukin-6 in human mesangial cells in culture. Here we investigated whether IL-1 regulates its own gene expression in human mesangial cells. Northern blot experiments showed that IL-1 induced IL-1 mRNA expression in a dose-dependent manner. The action of IL-1 on mesangial cells was mediated through the IL-1 receptor type I, which is constitutively expressed by mesangial cells. Recombinant IL-1 receptor antagonist blocked the IL-1 mRNA as well as interleukin-6 and interleukin-8 gene expression induced by IL-1. These data support the crucial role played by IL-1 in regulating mesangial cell cytokine genes within the glomerulus during immunological or inflammatory processes.

Blotting, Northern↗

The chronic proliferative disease of large granular lymphocytes.

This review deals with the chronic lymphoproliferative disease of large granular lymphocytes endowed with T and natural killer cell characteristics. The disease is sufficiently characterized to allow its distinction from other lymphoproliferative disorders of the T cell type. The heterogeneous clinical course and laboratory findings illustrate the complexity of the interaction between proliferating large granular lymphocytes and other haematopoietic cells.

Antigens, Differentiation, T-Lymphocyte↗

Integrated use of morphology, cytochemistry, and immune marker analysis to identify acute leukaemia subtypes.

One hundred and thirty-three acute leukaemia cases were evaluated by using a simplified sequence of morphological, cytochemical, and immunological investigations in order to obtain a correct leukaemia characterization that could have clinical relevance, rather than look for FAB-immunophenotype correlates. This approach offered an effective support to immediate therapeutic decisions and further investigations.

Acute Disease↗

The use of anthracyclines in adult acute lymphoblastic leukemia.

A critical review of the role of anthracyclines in the management of adult patients with acute lymphoblastic leukemia was performed to define current indications for their use. Major pertinent clinical series were reviewed with reference to anthracycline type, cumulative dosage and dose intensity, and administration schedule during both induction therapy and postremission consolidation, comparing results, whenever possible, with non-anthracycline treatment groups. A subgroup analysis was performed to evidentiate disease subtypes likely associated with a favorable outcome to anthracycline treatment. The results indicated that anthracyclines may still play a primary role in this setting. In particular, anthracyclines should be used at full therapeutic doses, especially during induction and early consolidation; idarubicin could be a better choice than daunorubicin or adriamycin; finally, an early brief intensive treatment with anthracyclines may provide an excellent probability of long-term disease-free survival in CD10+ t(9;22)-negative B-precursor adult ALL, obviating the need for prolonged maintenance or late reinduction therapy.

Adult↗

Effects of dexamethasone on pro-inflammatory cytokine expression, cell growth and maturation during granulocytic differentiation of acute promyelocytic leukemia cells.

In basal conditions, NB4 and HL-60, two acute promyelocytic leukemia cell lines, express high levels of tumor necrosis factor (TNF-alpha) mRNA, whereas they do not synthesize appreciable amounts of the transcripts coding for interleukin-1 beta (IL-1 beta) or interleukin-8 (IL-8). Upon granulocytic differentiation with all-trans retinoic acid (ATRA) or the combination of ATRA and granulocyte-colony-stimulating factor (G-CSF), significant amounts of IL-1 beta and IL-8 mRNAs accumulated in both cell types. These changes in mRNA levels were parallelled by the increased secretion of the two cytokines. Dexamethasone (DEX) had no effect on the induction of IL-1 beta mRNA, while it enhanced the G-CSF-, ATRA- and (ATRA+G-CSF) dependent secretion of the cytokine. In combination with ATRA and G-CSF, the corticosteroid increased the expression of leukocyte alkaline phosphatase, a late marker of granulocytic differentiation.

Alkaline Phosphatase↗

Therapeutic impact of adult-type acute lymphoblastic leukemia regimens in B-cell/L3 acute leukemia and advanced-stage Burkitt's lymphoma.

BACKGROUND: Adult B/L3-ALL is a rare disease subset characterized by an aggressive clinical course and a poor response to conventional adult ALL-type chemotherapy. Recent data from the GMALL Group showed that prognosis can be improved with an innovative treatment regimen. In the current retrospective survey we focus on therapeutic results obtained at our Institutions during a 15-year period with ALL-type regimens in 34 adults with either B/L3-ALL or advanced-stage Burkitt's lymphoma. METHODS: Five successive ALL treatment programs were developed. They included a homogeneous induction phase with early intrathecal chemoprophylaxis, multidrug postremission consolidation followed by cranial irradiation (4 trials), high-dose chemotherapy plus autografting (2 trials), late consolidation (2 trials), and variable-length maintenance (4 trials). Early response and prolonged disease-free survival rates were analyzed according to selected clinical and therapeutic variables. RESULTS: Overall, a complete remission was achieved in 62%, with a median duration of 1.6 years and a 10-year remission rate of 49%. A diagnosis of B/L3-ALL (p = 0.007), the use of idarubicin instead of adriamycin during induction (p = 0.018), a serum creatinine < 1.6 mg/dL, and an uninvolved central nervous system were associated with higher response rates. As regards long-term disease-free survival, results were significantly better in patients with < 1 x 10(9)/L L3/blast cells in the peripheral blood (p = 0.0029) and/or aged < 50 years (p = 0.04), and in those consolidated with the most recent rotational high-dose plus peripheral blood stem cell autotransplant regimen. CONCLUSIONS: According to the results presented, ALL-like regimens may still represent a worthwhile therapeutic choice. The use of idarubicin during induction, the prognostic subclassification of patients, a careful control of dysmetabolic complications, the selection of the proper chemo-radioprevention for meningeal disease and perhaps the introduction of high-dose chemotherapy supported by autologous stem cell rescue appear to be the mainstay of further improvements.

Adolescent↗

Mobilization and collection of PBSC in healthy donors: a retrospective analysis of the Italian Bone Marrow Transplantation Group (GITMO).

BACKGROUND AND OBJECTIVE: The number of allogeneic transplants of peripheral blood stem cells (PBSC) is rapidly increasing. Collection of PBSC in healthy subjects currently implies the administration of G-CSF or GM-CSF and, of course, the use of apheretic devices. These procedures involve potential risks, in particular the risk of leukemia secondary to growth-factor treatment. To evaluate the current practice of PBSC mobilization and collection, and initially assess the short-term side effects and efficiency of procedures, the GITMO (Gruppo Italiano Trapianti di Midollo Osseo) promoted a retrospective cooperative study among the Italian centers. METHODS: Seventy-six healthy individuals donating to their HLA-identical or partially matched sibling recipients in seven Italian centers form the basis of the present analysis. The data were retrospectively collected by proper forms, pooled and analyzed by means of a commercially available statistical soft package. RESULTS: All donors received G-CSF as mobilizing agent with different schedules according to each single center policy. A median of 2.5 (range 1-4) aphereses per donor were run. The most frequent side effect was bone pain. In no case did the medium term follow-up reveal subjective complaints or laboratory modifications. After G-CSF mobilization, WBC and lymphocytes counts increased to a maximum of (mean +/- SD) 48.1 +/- 15.6 x 10(9)/L and 4.2 +/- 1.5 x 10(9)/L, respectively. The peak was reached on day 5 in both cases. Platelets decreased after the apheretic procedures, reaching a minimum of (mean +/- SD) 77 +/- 26 x 10(9)/L on day 8 and returning to normal values on day 11. Overall, the apheretic collection yielded (mean +/- SD) 18.6 +/- 19.2 x 10(8)/kg donor body weight MNC; 10.4 +/- 5.7 x 10(6)/kg CD34+ cells; 90.6 +/- 75.9 x 10(4)/kg CFU-GM and 4.3 +/- 1.8 x 10(8)/kg CD3+ cells. The target dose of 4 x 10(6)/kg CD34+ cells was harvested in 51.3% donors after a single apheresis, in 85.5% after the second, and in nearly 100% after a maximum of 3 aphereses. INTERPRETATION AND CONCLUSIONS: These data demonstrate that collection of adequate numbers of circulating progenitors is feasible and well tolerated in healthy donors. However, only careful monitoring of donors and international cooperation will help to definitively assess the long-term safety of G-CSF for mobilization of PBSC.

Adolescent↗