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Biomedical subjects

G Leone

Publications and source records attributed to G Leone.

At least 289 records · Page 16Linked to original sources
PubMed1993

Replacement therapy with a purified protein C concentrate during initiation of oral anticoagulation in severe protein C congenital deficiency.

The case of an adult patient with moderately severe protein C deficiency (antigen 16%, activity 12%) is reported. Both parents had protein C levels compatible with heterozygous deficiency. Unlike other reported cases of severe protein C deficiency in adults, the onset of thrombotic symptoms occurred at 1 month of age; however, a symptom-free period until age 17 followed. Replacement therapy with a monoclonal antibody purified protein C concentrate was carried out during the initiation of oral anticoagulation after a course of i.v. heparin for deep vein thrombosis. The administration of the concentrate allowed maintenance of protein C above 50% until a stable therapeutic anticoagulation level could be obtained. This was reached within a short time, thus allowing safe administration of a loading dose of warfarin. We conclude that this approach to the prevention of skin necrosis seems more rapid and safer than previous schedules of oral anticoagulation in protein C-deficient patients.

Administration, Oral↗
PubMed1993

Blood pressure 24-hour pattern in two industrialized countries (Italy and Japan) with a different culture in salt intake.

This study investigates the blood pressure (BP) 24-hour pattern in representative samples of 2 industrialized countries, Italy and Japan, showing different cultures in salt intake. BP was monitored by means of a noninvasive ambulatory device whose readings were analyzed by means of chronobiometric procedures. The results show that the 24-hour BP pattern is not substantially different in Italian and Japanese subjects. In particular, the expected lower BP in the Italians was not detected despite their lower salt intake. Because the 24-hour mean BP value was seen not to be proportional to salt intake, the hypothesis is formulated that maintenance of the pressure regimen within a given range of variability is a principle of human physiology. To comply with this rule the Japanese people are supposed to have ethnically developed a certain resistance to dietary salt for which their cardiovascular apparatus is protected (phyletic escape to dietary sodium excess).

Adult↗
PubMed1993

Complete nucleotide sequence of the antithrombin gene: evidence for homologous recombination causing thrombophilia.

Antithrombin is the principle regulator of thrombin and other blood coagulation proteinases. It is a member of the serpin family of proteinase inhibitors. The genomic sequence of the antithrombin locus has been completed, revealing a gene spanning 13,477 base pairs from the transcription start site to the poly(A) addition signal. Nine complete and one partial Alu repeat elements were identified within the introns of the gene, with all but one orientated in the reverse direction. Inherited deficiency of antithrombin is associated with a venous thrombotic tendency. Restriction fragment mapping of the antithrombin genes in an individual with type I antithrombin deficiency identified an intragenic deletion in one allele. Localization of the deletion breakpoints involved restriction analysis and direct sequencing of amplified DNA spanning the deletion site. The deletion removed 2761 base pairs, affecting exon 5 and flanking introns, with the deletion ends contained within the left components of two Alu elements. It is likely, therefore, that the deletion arose by homologous recombination between the two Alu elements.

Adolescent↗
PubMed1993

Evidence of a hypercoagulable state in patients with acute lymphoblastic leukemia treated with low dose of E. coli L-asparaginase: a GIMEMA study.

Blood coagulation abnormalities induced by administration of E. coli L-asparaginase were investigated in 25 patients with acute lymphoblastic leukemia treated according to the GIMEMA ALL 0288 trial. Dosage of L-asparaginase was relatively low (6,000 U/m2/day for 7 days total dose 42,000 U/m2) as compared to the conventional dosages (120,000-140,000 U/m2 over 10-14 days). A significant decrease in fibronogen, plasminogen, alpha2-antiplasmin and antithrombin III was observed from day IV of L-asparaginase and it was maximum on day VIII, with return to the baseline levels on day XV. Protein C levels had only a borderline reduction, while no modification of protein S or factor VII was observed. Two of the patients investigated developed thrombosis. The presence of a prothrombotic state induced even by this low dosage of E. coli L-asparaginase was suggested by a significant increase of sensitive markers of hypercoagulability such as fibrinopeptide A, thrombin-antithrombin complexes, and prothrombin fragment F1 + 2.

Adolescent↗
PubMed1993

Trisomy 4 in acute myeloblastic and acute lymphoblastic leukemia.

We report three cases of trisomy 4 in acute leukemia. This alteration was detected as the sole cytogenetic abnormality in a case of FAB M4 leukemia; it occurred in association with 5q deletion in a case of M1, and concomitant with Ph chromosome and trisomy 17 in a case of L2 leukemia. The latter case represents the fourth report of trisomy 4 in acute lymphoblastic leukemia.

Adult↗
PubMed1993

The influence of long-term practice on mental rotation of 3-D objects.

We evaluated the influence of long-term practice on the performance of a mental rotation task in which subjects judged whether two 3-D objects presented in different orientations were identical. Stimuli and experimental conditions were analogous to those used by Shepard and Metzler. Sixteen subjects were selected, to test the influence of aptitude for mental imagery on this learning process. Subjects participated in 12 to 15 sessions over 6 weeks. Two catalogues of different stimuli were alternatively used during three (or six) consecutive sessions to determine the influence of complexity and familiarity of figures. For all subjects, the inverse of the velocity of mental rotation along the sessions was adequately fitted by a decreasing exponential curve. However, evidence for mental rotation did not disappear, even after 15 sessions. Asymptotic variations can be attributed to differences in stimuli as well as imaging skills of subjects. Our results lead to a new interpretation of the mental rotation process.

Adult↗
PubMed1993

Further investigations on the expression of HLA-DR, CD33 and CD13 surface antigens in purified bone marrow and peripheral blood CD34+ haematopoietic progenitor cells.

We evaluated the HLA-DR, CD33 and CD13 antigen expression on CD34+ haematopoietic progenitor cells (HPC) isolated from the bone marrow (BM) and peripheral blood (PB) of normal donors. The majority of both BM and PB CD34+ HPC expressed CD13 and HLA-DR. The coexpression of CD34 and CD33 was found in a minor CD34+ subset. After 7 d of culture in the presence of interleukin-3 and granulocyte-macrophage colony-stimulating factor, CD33 expression was detected in about 50% of HPC. At this point CD34 antigen expression was lost and CD13 and HLA-DR expression was partially lost. After 14 d of culture, the majority of HPC were CD33+. HPC maintained the capacity to generate colony forming unit granulocyte-macrophage but they lost the capacity to generate burst forming unit-erythroid. A correlation was found between the percentage of CD34+/HLA-DR+ cells and the total number of colony forming cells in unfractionated samples from BM and PB of patients with malignancies. These studies demonstrate that, in normal conditions, only a minor subset of CD34+ cells coexpress CD33 antigen either in BM or in PB and CD33 antigen is a lineage marker which is coexpressed with HLA-DR and CD13 on a progenitor committed to the granulocytic-macrophagic lineage.

Antigens, CD↗
PubMed1993

Haemopoietic CD34+ progenitor cells are not infected by HIV-1 in vivo but show impaired clonogenesis.

We evaluated the role of CD34+ bone marrow progenitor cells in vivo, in the pathogenesis of AIDS-related haematological abnormalities. The clonogenic activity of CD34+ cells from seven patients with HIV-1 infection, without bone marrow involving opportunistic infections or neoplasms, was assessed in semisolid cultures. The number of CFU-GM was significantly reduced as compared to the controls (P = 0.017), independently from myelotoxic therapy, while the number of BFU-E was not. The presence of retroviral sequences in CFU-GM colonies from four patients and in the total population of CD34+ cells from six patients with advanced stage HIV infection was investigated using the polymerase chain reaction. The presence of HIV-1 sequences was also searched for in a purified suspension of CD34+ cells after 3 weeks liquid culture. All these cells were always HIV-1 negative, while viral sequences were always detected in bone marrow mononuclear cells from these and other patients. The number of HIV-1 DNA copies decreased with increasing enrichment. At most 1:10,000 CD34+ cells are infected in vivo. Other mechanisms than direct viral infection of progenitor cells must account for the defective haemopoiesis in HIV-1 infected patients.

Adult↗
PubMed1993

Circadian rhythm of cardiac output, peripheral vascular resistance, and related variables by a beat-to-beat monitoring.

This study aimed to explore the 24-h patterns of stroke volume, cardiac output, and peripheral vascular resistance along with other correlated variables, such as left ventricular ejection time, ejection velocity index, thoracic fluid index, heart rate, and blood pressure. The study was performed on 12 clinically healthy subjects by means of a noninvasive beat-to-beat monitoring using the thoracic electric bioimpedance technique associated with the automated sphygmomanometric recording. Time data series were analyzed by means of chronobiological procedures. The results documented the occurrence of a circadian rhythm for all the variables investigated, giving relevance to the beat-to-beat bioperiodicity of cardiac output and peripheral vascular resistance. Temporal quantification of the investigated variables may be useful for a better insight of the chronophysiology of the cardiovascular apparatus.

Adult↗
PubMed1993

Anthracycline containing regimens in intermediate grade lymphoma. Italian Cooperative Study Group on Intermediate Grade Malignant Lymphoma.

From March 1991 to April 1992, 44 previously untreated patients with stage II to IV intermediate-grade non-Hodgkin's lymphoma (according to the Kiel classification) were entered in a phase III comparative trial. The objectives of the study were to compare the efficacy and safety of using idarubicin instead of doxorubicin in the combination chemotherapeutic regimen CHOP (cyclophosphamide, doxorubicin, vincristine, prednisolone). Forty-four patients were randomly assigned to receive either CI(idarubicin)OP or CH(doxorubicin)OP. The study is ongoing and so far no significant differences in complete response rate and (non-)hematologic toxicity have been observed.

Adult↗
PubMed1993

Treatment of multiple myeloma with autologous blood stem cell transplantation. Preliminary results of an Italian multicentric pilot study.

Starting from May, 1991, 35 untreated myeloma patients entered a multicentric pilot study to evaluate the feasibility of a program of PBSC transplantation for previously untreated myeloma patients. The schedule was as follows: 2 cycles of VAD followed by CY, 7 g/mq+G-CSF (Granulokine, Roche) for 14 days, to increase and collect PBSC. The subsequent conditioning regimen was Melphalan+Busulfan followed by G-CSF. As maintenance R alpha-2 IFN was given, until relapse. The median follow-up is 14 months (4-22). On April 1993, 34 patients received at least 2 cycles of VAD, 27 were submitted to PBSC collection, 22 received conditioning regimen plus PBSC and 16 of them are in the maintenance treatment with IFN. Considering 28 patients for an intention to treat evaluation (35-7 in treatment), responding patients are 71% with 46% who achieved CR. White cells and platelets raised to > 1000/mmc and > 50,000/mmc after a median period of 10 and 13 days, from CY, and 11 and 14 days from transplant, respectively. Two patients relapsed, 2 others died while in PR because of CMV epatitis and candida pneumonia. The median number of CD34+ cells and CFU-GM was 24.75 x 10(6)/kg b.w. and 28.1 x 10(4)/kg b.w. respectively. In conclusion this treatment seems to be feasible and with low toxicity, but a longer follow-up is needed to evaluate the progression free survival of the high proportion of responding patients that we observed.

Adult↗
PubMed1993

In vitro expansion of CD34+ cells mobilized with chemotherapy and G-CSF.

Hemopoietic CD34+ progenitors were isolated by immunomagnetic method from normal bone marrow (BM) or from peripheral blood (PB) of patients with non-Hodgkin's lymphoma treated with chemotherapy and granulocyte colony-stimulating factor (GCSF). Aliquots were seeded in long-term cultures (LTC) on bone marrow-derived stromal layers; non-adherent and adherent clonogenic content of the cultures was assayed weekly. The final recovery and the clonogenic efficiency of the CD34+ cells were slightly higher in PB samples than in BM controls. In long term cultures PB cells sustained hemopoiesis as much as BM cells; at week 3 and 4 PB total mononuclear cells and CD34+ cells showed a non-adherent cell recovery higher than the respective BM controls. Furthermore, PB CD34+ cells were expanded in liquid culture in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF alone or combined with interleukin 3 (IL3), stem cell factor (SCF), interleukin 1 (IL1), interleukin 6 (IL6). The combination of GM-CSF, IL3, SCF, IL1 and IL6 produced the maximum increase of both mononuclear cells (30-fold) and granulocyte-macrophage colony forming units (CFU-GM) (4.6-fold) after 7 days of cultures; yet after 14 days a strong decrease of the CFU-GM occurred. These data suggest that G-CSF following chemotherapy mobilizes both early and committed hemopoietic progenitors.

Antigens, CD↗
PubMed1993

Five-year experience in PBSC collection: results of the Catholic University of Rome.

Several authors have reported a faster immunological and hemopoietic post-transplant reconstitution using autologous peripheral blood stem cell (PBSC) than using autologous bone marrow stem cells. A large number of PBSC can be collected by leukapheresis during the hematological recovery after induction or salvage chemotherapy. In our experience we demonstrated that several separators, even if they have different results in mononuclear cell (MNC) yields, red blood cell and platelet contaminations, are able to collect PBSC for autotransplantation in patients with several malignant diseases and different status of disease. Eighty three patients were submitted to 590 leukapheresis procedures using 4 different blood cell separators: the results showed that all employed protocols are efficient in the collection of peripheral MNC even if after the widespread use of granulocytecolony stimulating factor (G-CSF) in the harvesting phase, the blood cell separator efficiency in terms of MNC is reduced. The use of GCSF in combination with other growth factors, during chemotherapy mobilization could simplify, in the future, this therapeutical program even if improvements in the efficiency of PBSC collection protocols are required.

Adolescent↗
PubMed1993

Survival after PBSC transplantation and comparison of engraftment speed with autologous and allogeneic marrow transplantation: results of a multicenter study.

We have analyzed the results of a multicenter study on peripheral blood stem cell transplantation (PBSCT) performed on 55 patients suffering from various neoplastic diseases. After myeloablative therapy, they received a median of 6.8 x 10(8)/kg MNC and 11.4 x 10(4)/kg CFU-GM harvested by a median of 9 apheresis after mobilization with chemotherapy alone. As of date, 34 of the 55 patients are alive and 28 of them are in continuous complete remission after a follow-up of 30 months. The probability of survival was related to the disease status at transplant, CR/PR vs. PD (p = 0.0001) and the bone marrow involvement, BM-vs. BM+ (P = 0.009). Furthermore, a comparative study on speed of engraftment and clinical management was conducted on the 55 PBSCT patients as well as on 41 autoBMT and 52 alloBMT patients. Days to reach WBC > 1.0 x 10(9)/L, PMN > 0.5 x 10(9)/L and PLT > 50 x 10(9)/L was 12/14/33 for PBSCT, 17/20/23 for ABMT and 15/16.5/18 for BMT, respectively. Days with fever > 38 degrees C, systemic antibiotic therapy and length of hospitalization was 3/12/36 for PBSCT, 5/18.5/42 for ABMT and 9/25/46 for BMT respectively.

Bone Marrow Transplantation↗
PubMed1993

Evaluation of a new whole blood cytometric lymphocyte transformation test for immunological screening.

Lymphocyte transformation test (LTT) is usually performed by 3H-thymidine (3H-TdR) incorporation of phytohemagglutinin stimulated lymphocytes. This test presents a lack of standardization as well as a great variability of results making it difficult to compare the results carried out by different laboratories. Flow cytometry (FCM) can precisely evaluate cell kinetics by measuring the DNA content of stained nuclei. We tested a new ready-to-use kit for the blastogenic response of mitogen stimulated lymphocytes in FCM for clinical immunological screening (Blastest, Ylem). Separated peripheral blood lymphocytes from the same donors were also tested with the 3H-TdR method at 72h and results compared to FCM. Our results show a significant correlation between data obtained from FCM and 3H-TdR method. We show that there are no differences in results between different cytometers if CVs are low. Flow cytometry is more precise and reproducible and makes a better standardization feasible, it also offers a simpler and faster way for routine LTT enabling a wider clinical use.

Adolescent↗
PubMed1993

Granuloblastic masses in the breast: report of two cases.

Two patients with granuloblastic masses of the breast, onsetting at diagnosis and as first relapse site of acute myeloid leukemia are reported. The first case had been diagnosed initially as a carcinoma, and the patient underwent bilateral mastectomy. Acute leukemia was only revealed by histology of the surgical specimen. In the second case a second neoplasia, occurring during acute leukemia, was suspected: a fine needle aspirate of the breast mass showed a leukemic infiltrate. Involvement of breast during acute myeloid leukemia is a rare event and, in our experience, of bad prognostic significance. Mammary glands may be a sanctuary for leukemic cells, contributing to unresponsiveness to chemotherapeutic agents.

Acute Disease↗