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A Tichelli

Publications and source records attributed to A Tichelli.

At least 91 records · Page 5Linked to original sources
PubMed1996

[Bernard-Soulier thrombocytopenia: clinical significance of a rare disorder].

We present 5 cases with thrombocytopenia and abnormal platelet function. The diagnosis of Bernard-Soulier syndrome was suspected in some subjects of advanced age on the ground of morphologic changes in the thrombocytes and of low platelet counts with or without prolonged bleeding time. The platelets showed normal aggregation with adrenalin, ADP and collagen but abnormal agglutination with ristocetine. All patients had normal von Willebrand factor levels in plasma. Flow cytometry demonstrated on thrombocytes lack of GP Ib expression of varying degree in comparison to normal controls, using various anti-GP Ib-antibodies (CD42b). The combination of these findings confirmed the diagnosis of Bernard-Soulier syndrome with varying expression of GP Ib. Flow cytometry and the use of specific monoclonal antibodies may be a rapid and reliable diagnostic tool. Differential diagnosis and treatment strategies are discussed. A congenital thrombopathy should always be considered in patients with thrombocytopenia of unknown origin and abnormal platelet morphology.

Adult↗
PubMed1996

Frequent clonal loss of heterozygosity but scarcity of microsatellite instability at chromosomal breakpoint cluster regions in adult leukemias.

Microsatellites are important highly polymorphic genetic markers dispersed in the human genome. Using a panel of 22 (CA)n repeat microsatellite markers mapped to recurrent breakpoint cluster regions specifically involved in leukemia, we investigated 114 adult leukemias (25 acute lymphocytic leukemia [ALL], 32 acute myeloid leukemia [AML], 36 chronic lymphocytic leukemia [CLL], and 21 chronic myeloid leukemia [CML] in chronic phase) for somatic mutations at these loci. In each patient, DNA from fresh leukemia samples was analyzed alongside normal constitutive DNA from buccal epithelium. We detected loss of heterozygosity (LOH) in 81 of 114 patients (ALL 16/25, AML 25/32, CLL 30/36, CML 10/21). Deletions were most often seen in ALL at 11q23 and 19p13; in AML at 8q22 and 11q23; in CLL at 13q14.3, 11q13, and 11q23; and in CML at 3q26. Only six deletions were reported in 74 karyotypes analyzed, whereas in these same cases, 91 LOH events were detected by microsatellites. Of 26 leukemias with a normal karyotype, 16 nevertheless showed at least one LOH by microsatellite analysis. Replication errors were found in 10 of 114 patients (8.8%). Thus, microsatellite instability is rare in leukemia in contrast to many solid tumors. Our findings suggest that in adult leukemia, LOH may be an important genetic event in addition to typical chromosomal translocations. LOH may point to the existence of tumor suppressor genes involved in leukemogenesis to a degree that has hitherto been underestimated.

Adult↗
PubMed1996

[Transplantation of allogeneic peripheral hematopoietic progenitor cells instead of bone marrow].

In a pilot study we tested the feasibility and safety of peripheral blood precursor cells instead of bone marrow cells for allogeneic transplantation. 13 patients, 7 male and 6 female between 24 and 52 years of age with hematological malignancies (10 with acute leukemias, 3 with myeloproliferative syndromes-were conditioned for bone marrow transplantation with VP-16, cyclophosphamide and total body irradiation followed by graft-versus-host disease prophylaxis with cyclosporin and methotrexate. Precursor cells were mobilized in the donors by granulocyte colony stimulating factor (G-CSF, Neupogen) 10 micrograms/kg s.c. from day-5 on. A total of 14.05 x 10(8) nucleated cells/kg recipient body weight (range 9.52-20.23 x 10(8)/kg), corresponding 6.82 x 10(6)/kg CD 34+ cells (range 1.43-15.84 x 10(8)/kg) or 113.9 x 10(4) CFU/kg (range 45.15-431.64 x 10(4)/kg) were collected by 3 phereses (1 patient 5 phereses) of 27-45 liters and infused without further manipulation. All patients engrafted with a recovery of total white blood cell count > 1 x 10(9)/l on day 15 (day 10-26) and of platelets > 20 x 10(9)/l on day +18 (day 12-39). 11 of the 12 patients developed aGvHD, 8 with grade II, 3 with grade > or = II. 9 of 13 patients are alive and well +4 to +16 months posttransplant, 3 patients died of aGvHD, one of veno-occlusive disease. These preliminary results confirm the capacity of peripheral blood precursor cells for rapid and complete engraftment in the allogeneic setting. Whether they induce more or equal aGvHD is an open question. Their value in allogeneic transplantation is currently under investigation in prospective randomized trials.

Adult↗
PubMed1996

[Autologous transplantation of hematopoietic precursor cells following CD34 selection].

Peripheral blood is increasingly used instead of bone marrow as a source of hemopoietic precursor cells for transplantation. The optimal technique still needs to be defined. Selection of CD34+ cells in transplant material may be of benefit in allogeneic and autologous peripheral blood precursor cell transplantation (PBPCT), since it allows elimination of unwanted CD34-negative cells, such as T-cells and contaminating tumor cells. We have evaluated the feasibility of CD34 selection in PB transplants and studied hemopoietic reconstitution after autologous transplantation of CD34 selected precursor cells. Between August 1994 and June 1995 CD34 selection was performed on 12 transplants for 9 patients with malignant disease (non-Hodgkin lymphoma [n = 5]; Ewing sarcoma [n = 1]; chronic lymphocytic leukemia [n = 1]; breast cancer [n = 1]; multiple myeloma [n = 1]). PBPC were collected with a Fenwall CS 3000 harvester after stimulation with G-CSF. For selection of CD34+ cells the Ceprate LC34 system (CellPro) was used. A median CD34 purity of 73% (range 40-94%) was achieved. The median number of CD34 positive cells per transplant was 4.8 x 10(6)/kg body weight (range 0.7-15.8). The median number of colony forming cells per transplant was 31 x 10(4)/kg body weight (range 1.5-131.3). For autologous PBPCT the minimal number of CD34 positive cells required in the transplantate was arbitrarily set at 1.0 x 10(6)/kg body weight. This number was achieved in 10 of the 12 transplants. The median loss of CD34+ cells during selection was 1.5 x 10(6)/kg body weight (range 0.2-6.4). In 2 patients the total number was reduced to below the critical value of 1.0 x 10(6)/kg. 7 of the 9 patients received the CD34 selected transplant after intensive chemotherapy and irradiation. The median follow-up time after PBPCT was 196 days (range 62-278). All 7 patients are now alive and with normal hemopoietic function. A granulocyte count above 0.5 x 10(9)/l and a platelet count above 20 x 10(9)/l was achieved on day 14 (median), and on day 19 after PBPCT. We conclude that CD34 selection is technically feasible and that CD34 selected cells can be used for PBPCT. The procedure is time consuming and expensive; it requires complex organization at laboratory level, and the benefit of CD34 selection with regard to T-cell depletion and tumor purging still needs to be proven. However, CD34+ selection is likely to open new perspectives in transplantation medicine.

Adolescent↗
PubMed1996

Severe neutropenia in T-large granular lymphocyte leukemia corrected by intensive immunosuppression.

Optimum treatment of severe neutropenia, a major factor for morbidity and mortality in T-large granular lymphocyte (LGL) leukemia, is undefined. We observed a rapid improvement of the neutrophil count in a patient with T-LGL leukemia and severe neutropenia after the combined administration of antilymphocyte-globulin (ALG), cyclosporin A, prednisone, and granulocyte colony-stimulating factor (G-CSF). Although G-CSF treatment was terminated after 7 days, the neutrophil count has persisted above 1.0 x 10(9)/1 for up to 6 months now. Oral methotrexate is given continuously as treatment for T-LGL leukemia. The response to this immunosuppressive regimen suggests a T-cell-mediated mechanism as the underlying cause for neutropenia in T-LGL leukemia.

Humans↗
PubMed1996

Indications for haemopoietic precursor cell transplants in Europe. European Group for Blood and Marrow Transplantation (EBMT).

Information on 17,206 haemopoietic precursor cell transplants performed in 12 European countries between 1991 and 1993 was used to assess the number of transplants per million inhabitants per year by principal indication and donor source. 16.6 transplants were performed per million inhabitants per year with a range of 9.4-27.7. Differences between countries may be due to the availability of beds and resources or to divergent opinions about treatments. We used the coefficient of variation (CV) to assess the degree of agreement between clinicians with regard to different procedures and indications, with a cut-off of < or = 45% to indicate consensus. The rate of allogeneic transplantation between the 12 countries was more 'homogenous' than that of autologous transplantation (mean 6.8 per million inhabitants, range 5.2-9.5, CV 20% versus mean 9.8 per million inhabitants, range 3.6-18.4, CV 40%). Consensus was found for allografting in chronic myeloid leukaemia (CML) in first chronic phase (CV 19%), CML in later phases (CV 31%), acute myeloid leukaemia (AML) in first complete remission (CV 41%), AML beyond first complete remission (CV 34%), acute lymphoblastic leukaemia beyond first complete remission (23%), and severe aplastic anaemia (29%). Consensus for autografting was observed for Hodgkin's disease (CV 44%), non-Hodgkin's lymphoma (CV 44%), and AML beyond first remission (CV 41%). With this method an assessment of medical opinion can be made in spite of the different availabilities of resources. These data reflect the state of the art in haemopoietic precursor cell usage in Europe; they provide a basis for patient counselling and health-care planning.

Bone Marrow Transplantation↗
PubMed1996

Splenectomy as an adjuvant measure in the treatment of severe aplastic anaemia.

The role of splenectomy in aplastic anaemia (AA) is controversial. The hazards of operating on a severely pancytopenic patient, the fear of compromising the patient's immune function, and the improvement of non-surgical treatment have made splenectomy unpopular in this disease. We have evaluated positive and adverse effects of splenectomy in 80 patients with severe aplastic anaemia (SAA) treated with antilymphocyte globulin (ALG) (group A), using 52 nonsplenectomized ALG patients as controls (group B). All patients survived the operation. Nonfatal complications of surgery occurred in 10 (12.5%). Splenectomy induced a significant increase of peripheral blood neutrophils, reticulocytes and platelets within 2 weeks, followed by a continuous increase of all values over the following weeks. 28/132 patients (21%) developed a late clonal disorder of haemopoiesis, paroxysmal nocturnal haemoglobinuria (PNH) or myelodysplastic syndrome (MDS), or both. Their incidence was identical in groups A and B. 13/28 (59%) died, 10/17 (59%) in group A and 3/11 (27%) in group B (not significant (n.s.)). Overall probability of survival at 18 years after ALG was 51+/-6% for group A and 61+/-7% for group B (n.s.). We conclude that splenectomy in AA is safe. It induces an immediate increase of peripheral blood counts and, thereafter, a continuous improvement of haemopoiesis. It does not increase the incidence of late clonal complications but has a borderline effect on mortality from these disorders. Splenectomy should be reconsidered in selective nontransplanted patients who have prolonged transfusion requirements despite otherwise optimal treatment.

Adolescent↗
PubMed1996

Peripheral blood pressure cells transplants across a major histocompatibility barrier in rabbits: positive effects of a higher number of precursor cells?

Peripheral blood precursor cells (PBPCs) are used with increasing frequency for hematopoietic transplants and have more or less replaced autologous bone marrow transplants. First clinical and experimental reports document the feasibility of PBPCs as a source for allogeneic transplants. Few data exist on the optimal procedure and the ideal number of cells for the transplant. We have previously shown in rabbits that PBPCs can be used for transplants even across a major histocompatibility barrier. We used this model to test whether the number of transplanted precursor cells would influence graft outcome. Adult outbred Red Burgundy rabbits were used as donors, New Zealand White rabbits of the opposite sex as recipients. One individual donor was taken for one individual recipient. Conditioning consisted of single-dose total body irradiation of 10 Gy followed by a short course of cyclosporine to enhance engraftment. Donor animals were treated with recombinant human granulocyte-colony-stimulating factor, 10 micrograms/kg subcutaneously daily from day -2 until day +9. PBPCs were obtained from the artery of the donor animal by repetitive centrifugation of 2 x 40 ml heparinized blood on each day of donation, i.e. days 0, +2, +3, +6, +8, and +10 and infused without further manipulation. Eight animals underwent transplantation. Seven took the grafts, six died of graft-versus-host disease and pneumonia between days 12 and 55 (median survival of all animals: 34 days). One animal was still alive after 120 days. Transplanted nucleated cells varied from 7.3 to 15.4 x 10(8)/ kg (median 9.2 x 10(8)/kg) and CFU-GM from 12.3 to 176.8 x 10(4)/kg (median 42 x 10(4)/kg). Survival tended to increase with more CFU-GM) r = 0.716, p = 0.0704). These data confirm that allogeneic PBPCs can engraft across a major histocompatibility barrier and suggest that a higher number of CFU-GM might be advantageous.

Animals↗
PubMed1996

Fatal vascular leak syndrome with extensive hemorrhage, peripheral neuropathy and reactive erythrophagocytosis: an unusual complication of recombinant IL-3 therapy.

A 39-year-old patient with severe aplastic anemia (AA), resistant to therapy, received recombinant human IL-3 (rhIL-3) on a phase I/II trial. During treatment she developed disseminated skin lesions, suggestive of vasculitis, and severe progressive peripheral neuropathy culminating in complete paralysis. She died 25 days after beginning treatment from profuse bleeding. On autopsy, evidence of vascular leaks with widespread bleeding and extensive hemorrhagic involvement of peripheral nerves was found. An additional feature was massive reactive erythrophagocytosis in lymph nodes, spleen and bone marrow. The coincidence between rhIL-3 administration and the dramatic events suggest a causal relation. As a possible pathogenic mechanism, an rhIL-3 induced excessive stimulation of macrophages and production of secondary cytokines such as tumor necrosis factor (TNF) is suggested. TNF is considered as a major factor in the development of both a vascular leak and reactive erythrophagocytosis. This case report can be regarded as an example of the possible unusual pathologic phenomena we may expect to see in the near future with increasing use of growth factors.

Adult↗
PubMed1996

Treatment of Aplastic Anemia.

There is general agreement that in children and adolescents with an HLA-identical or syngeneic sibling, bone-marrow transplantation (BMT) should be performed without delay. More controversial are young-to-middle-aged adults with an HLA-identical sibling. Because of comparable survival rates, some centers advocate BMT; others advocate immunosuppression as primary treatment. BMT cures severe aplastic anemia (SAA), but has a higher early mortality. Immunosuppression usually induces hemopoietic improvement and has hardly any early mortality. However, there are late problems. After immunosuppression, there may be relapse and clonal hematopoietic disease. After BMT, there may be late graft failure, severe or even fatal chronic graft-versus-host-disease (GVHD). Both procedures are followed by a slight increase in second malignancies. Retrospective studies show no significant differences in long-term survival between the two treatment modalities. In patients over the age of 40, immunosuppression is favored by most centers because in this age group there is a very high transplant-related mortality with BMT. Androgens and hematopoietic growth factors have hardly any role in therapy of SAA. Splenectomy helps some patients with severe thrombocytopenia and problems with supportive care, but does not improve the overall prognosis. BMT with unrelated donors has usually been performed in late stages of the disease with disappointing results.

Journal Article↗
PubMed1996

Allogeneic peripheral blood precursor cell transplants in rabbits.

This report summarizes a series of experiments undertaken to evaluate the role of mobilized peripheral blood precursor cells (PBPC) for transplantation across a major histocompatibility barrier. Adult outbred red Burgundy rabbits were used as donors, New Zealand white rabbits of the opposite sex as recipients. Conditioning consisted of single dose total body irradiation (TBI) of 10 Gy supported by a short course of cyclosporine to enhance engraftment. Human recombinant G-CSF at a dose of 10 micrograms/kg was used for mobilization of precursor cells. Three methods of PBPC transplants were tested initially in 5 animals each. PBPC were collected and infused at once on day 0; collected initially, cryopreserved for one month, infused on day 0 and followed by 3 additional fresh donations or collected and infused on 6 occasions between days 0 and + 11. 13 animals engrafted, 2 became complete, longterm chimeras. Survival was best in the group given repetitive infusions (39 days median, 12 days to > 180 days, range). 10 additional animals were transplanted as in the last group and the number of transplanted nucleated cells (10.5 x 10(8)/kg median, 7.3 - 15.7 x 10(8)/kg range) and colony forming units CFU-GM (42 x 10(4)/kg median, 12.3 - 176.8 x 10(4)/kg range), were compared with outcome. Median survival of the 10 animals was 29 days (12 - 55 days range; 1 autologous reconstitution). Survival did not correlate with total nucleated cells per kg (r = 0.10; p = 0.79), but there was a trend to prolong survival with higher numbers of CFU-GM per kg (r = 0.47; p = 0.19). These data show that allogeneic PBPCT can engraft across a major histocompatibility barrier, that the high number of CFU-GM per kg might be advantageous, but also that additional methods are warranted to reduce acute GvHD.

Animals↗
PubMed1996

Randomized study of the combination of hydroxyurea and interferon alpha versus hydroxyurea monotherapy during the chronic phase of chronic myelogenous leukemia (CML Study II). The German CML Study Group.

It is the long-term goal of the German CML Study Group and of the Süddeutsche Hämoblastosegruppe (SHG) to improve survival of patients with chronic myelogenous leukemia (CML). In a first randomized study (CML Study I) monotherapies with hydroxyurea or interferon alpha (IFN-alpha) were compared with a standard busulfan regimen with regard to duration of the chronic phase and survival. The main results of this study were published, 1-3 and a long-term follow up is planned. In a second randomized study the effect of the combination of IFN-alpha and hydroxyurea versus hydroxyurea monotherapy on survival is being investigated. This paper provides a first preliminary report on the study concept, patient recruitment, state of documentation and initial patients' characteristics 9 months after closure of the study.

Adult↗
PubMed1996

Late-onset keratoconjunctivitis sicca syndrome after bone marrow transplantation: incidence and risk factors. European Group or Blood and Marrow Transplantation (EBMT) Working Party on Late Effects.

The incidence, time course and risk factors associated with late-onset keratoconjunctivitis sicca syndrome after bone marrow transplantation (BMT) was evaluated in a multicenter retrospective cohort study conducted by the European Group for Blood and Marrow Transplantation (EBMT) Working Party on Late Effects. Data were requested from participating European centers on all patients transplanted up to December 1980 and on all patients treated during the year of 1984. Twenty-eight centers reported data on 258 patients and 248 could be evaluated for keratoconjunctivitis. Forty-eight of the 248 (19%) patients developed a keratoconjunctivitis sicca syndrome between 3 and 127 months (13.8 months) after BMT. The actuarial probability of developing dry eyes was 21 +/- 3% at 15 years. Thirty-three of the 48 (69%) patients with sicca syndrome had graft-versus-host disease (GVHD) compared to 60 of 200 (30%) patients without keratoconjunctivitis (P < 0.0001). The probability of developing keratoconjunctivitis sicca syndrome at 15 years was 38 +/- 6% for patients with and 10 +/- 3% (P < 0.0001) for those without chronic GVHD. Factors associated with an increased risk for late-onset of keratoconjunctivitis are chronic GVHD (relative risk 3.5; CI, 1.9-6.9), female patients (5.6; CI, 1.6-18.8), age older than 20 years (3.1; CI, 1.6-5.6), single dose irradiation for preparation to BMT (3.8; CI, 1.3-11.3) and methotrexate for prevention of GVHD (3.6, CI, 1.05-12.8). Late-onset kerato- conjunctivitis is a frequent ocular complication of BMT. With adequate treatment, severe corneal defects can be avoided. It occurs more frequently in patients with chronic GVHD, but, independent of chronic GVHD, more frequently in older patients and in females as it is observed in de novo Sjögren's syndrome. These data support the current concept that chronic GVHD is a reaction of both, allo- and autoimmunity.

Adolescent↗
PubMed1996

Indicators of haematopoietic recovery after bone marrow transplantation: the role of reticulocyte measurements.

The aim of this project was to study haematological recovery in patients following different types of bone marrow transplantation (BMT). Forty-three patients were analysed. The duration of haematopoietic suppression following conditioning regimens was much shorter in 12 peripheral blood stem cell transplantation patients than in 19 allogeneic BMT patients and in 12 autologous BMT patients. Among 12 different variables, the parameters with the highest specificity or predictive value for monitoring recovery in these patients were the absolute neutrophil count (ANC) at the classical cut-off point of 0.5 x 10(9)/l, an absolute reticulocyte count (RET) above 20 x 10(9)/l and a high fluorescent reticulocyte fraction (HFR) above 5%,. It is suggested that these parameters be used as the reference measurements for monitoring haematological recovery in similar studies. Among these variables, the HFR fraction was the earliest and most sensitive index of engraftment in 79.1% of patients, HFR recovery requiring a median time of 13 days after infusion, in comparison with a median period of 19 and 18 days, respectively, for RET and ANC (P<0.0001).

Adolescent↗
PubMed1995

[Bone marrow transplantation].

Bone marrow transplantation (BMT) has evolved from an experimental undertaking to an established therapeutic strategy for hematological neoplasias, severe aplastic anemia, congenital immunological and metabolic disorders and some solid tumors. This report summarizes the main indications for autologous and allogenic transplants, the prerequisites and potential techniques, early and late complications as well as preventive and therapeutic strategies. The results of 397 BMT, 357 allogeneic and 40 autologous transplants, performed in Basel between 1973 and 1995, illustrate the present potential and main prognostic factors: stage of disease, age and histocompatibility. 50% of the patients treated with an allogeneic BMT from an HLA-identical sibling early in the disease are alive 15 years post BMT, 80% free of disease and reintegrated into work and family. New strategies are testing the use of unrelated HLA-compatible volunteer donors and the potential of mobilized peripheral blood precursor cells instead of bone marrow for allogeneic and autologous transplants.

Bone Marrow Transplantation↗
PubMed1995

[Flow cytometry identification of CD34-positive cells].

In the present study three clinical applications of flow-cytometric quantification of CD34-positive cells in the field of blood and marrow transplantation are evaluated. By daily determination of CD34-positive cells in the peripheral blood after mobilization of stem cells with chemotherapy or growth-factors it is possible to set the optimal time for collection of the transplant material. Thereafter the yield of CD34-positive cells within the harvested material is determined. Finally, the efficacy of positive CD34 selection using a biotin-avidin column is evaluated. Initial experience is presented here.

Antigens, CD↗
PubMed1995

[Hydroxyurea, erythrocyte volumes and hemoglobin F].

Hydroxyurea is used in the treatment of sickle cell anemia and beta-thalassemia major to increase the content of hemoglobin F (HbF) and presumably ameliorate clinical symptoms. Under therapy with hydroxyurea an increase of the mean corpuscular volume (MCV) of the erythrocytes can be observed. To evaluate a possible estimation of the content of HbF using the increase of MCV under treatment with hydroxyurea, we measured MCV and HbF during therapy with hydroxyurea. The median MCV before therapy was 87.8 fl (range 74.3-95.7) and under hydroxyurea 104.1 fl (81.0-139.5), and the median HbF 1.8% (0.1-5.4). Although both MCV and HbF increased under treatment with hydroxyurea, a linear correlation between these two parameters was not detectable. Therefore, MCV cannot replace the measurement of HbF.

Erythrocyte Indices↗