Comparison of forward and backward gait in males with and without intellectual disabilities.

BACKGROUND: Intellectual disabilities (ID) affect both cognitive and motor functions. The backward gait is a daily activity and its assessment is used for fall risk estimation and training in the general population. For proper use of backward gait as a rehabilitation tool and in fall prevention programmes for people with ID, it is necessary to determine the backward gait characteristics in the ID population. The aim of this study was to compare the differences between forward and backward gait in persons with nonsyndromic mild and moderate ID, persons with Down syndrome (DS) and a control group of healthy adults. METHODS: Fifty males divided into four groups (mild ID: n = 15, moderate ID: n = 19, DS: n = 6, controls: n = 10) participated in this study. All participants were asked to walk both forward and backward, barefooted and at their natural velocity on a Zebris FDM platform. The Kruskal-Wallis H test was used to compare differences between the analysed groups in forward and backward gait. The Mann-Whitney U test was used to compare the differences between forward and backward gait within each group. RESULTS: The velocity was significantly slower in moderate ID and DS compared to controls in forward and backward gait. When comparing forward and backward gait within each group, the gait velocity decreased in backward gait compared with forward gait by 21.80% in controls, by 33.89% in mild ID, by 34.45% in moderate ID, and by 40.32% in DS. In both moderate ID and DS, the mean backward velocity was slower than 2.16 km/h, the velocity used to identify elderly fallers in the general population. CONCLUSIONS: Gait velocity was especially affected in DS and moderate ID compared with controls. In both mentioned groups, the backward gait velocity suggests an increased risk of falling. Future studies are necessary to examine the possibility of improving balance control and leg muscle strength by backward walking training in the ID population.

Clinical presentation and natural history of patients with essential thrombocythemia and the Philadelphia chromosome.

Six women presented with the clinical picture of essential thrombocythemia (ET) without the anemia, marked splenomegaly, and extreme leukocytosis characteristic of chronic myelogenous leukemia (CML). All had the Philadelphia chromosome on karyotype analysis of the bone marrow. Peripheral basophilia was present in four cases, providing a clinical clue that the Philadelphia chromosome might be present. Marrow biopsy showed granulocytic hyperplasia and either small megakaryocytes or sheets of megakaryocytes with marked atypia, findings that are more typical of CML than ET. The clinical importance of finding the Philadelphia chromosome in patients who seem to have ET is in assessing prognosis. ET generally follows a chronic, indolent course. However, five of these six patients who had the Philadelphia chromosome underwent clinical transition to the accelerated phase of CML or blastic leukemia in 4-7 years.

Differences in nonspecific esterase from normal and leukemic monocytes.

Nonspecific esterase (NSE) is used to identify normal and leukemic mononuclear phagocytes cytochemically. It can be demonstrated by the hydrolysis of alpha-naphthyl acetate or butyrate. NSE from leukapheresed leukemic monocytes were extracted with several types of detergent and grouped into two isoelectric point (pl) categories based on the ease of solubility: pl 5.7-6.3 (8 bands) greater than or equal to pl 6.6-7.6 (6 bands). Normal monocytes yielded only the pl 5.7-6.3 isozymes. Isozymes from both leukemic and normal monocytes were inhibited similarly by sodium fluoride, pH less than 4.7, and a serine active site inhibitor. All isozymes were bound by Sepharose-concanavalin A (Con-A) and displayed similar substrate preferences and pH v activity slopes. Under the conditions of detergent solubilization, the smallest mol wt species retaining enzymatic activity was 50 +/- 5 kd. Despite these similarities, the isozymes of pl 5.7 through 6.3 and pl greater than 6.3 exhibited different degrees or types of inhibition by phenylmethylsulfonyl fluoride (PMSF), resistance to heat and antigenic character. Thus, the esterase isozymes represent two families of glycoproteins, both of them probable cell surface enzymes, resembling classical liver carboxyl or B-esterases (EC 3.1.1 1).

Fatal cardiac toxicity in bone marrow transplant patients receiving cytosine arabinoside, cyclophosphamide, and total body irradiation.

Three patients developed fatal cardiac toxicity from the combination of cytosine arabinoside, cyclophosphamide, and total body irradiation while undergoing preparation for a bone marrow transplant. The pattern of the toxicity was unique for this combination of ablative chemotherapy. All three patients had autopsies demonstrating characteristic myocardial and pericardial toxicity. The cardiotoxic effects of this combination may be averted by lowering the dose of the cyclophosphamide.

In vitro analysis of donor bone marrow following monoclonal antibody treatment for the prevention of acute graft versus host disease.

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality following bone marrow transplantation. The in vitro removal of the GVHD-causing T-lymphocytes from donor marrow is one approach which could control this complication. Treatment of the donor bone marrow with lectins and erythrocyte-forming rosette depletion, anti-T-cell antisera or monoclonal antibodies are methods currently being tested to accomplish this. CT-2 is an immunoglobulin monoclonal antibody specific for the T-cell erythrocyte-forming rosette receptor. Bone marrow from 23 consecutive donors was treated in vitro with CT-2 and complement, prior to infusion, as a potential means of controlling GVHD. Surface marker analysis using erythrocyte-forming rosetting, and OKT-3 and OKT-11 monoclonal antibodies on paired samples of treated and untreated marrow demonstrated a mean depletion to 1% of the original number of T-cells. Proliferative responses to alloantigens and mitogens as well as cytotoxic and natural killer cell function were tested and found to be markedly reduced. Despite these effects on T-lymphocytes, viable hematopoietic stem cell colonies were retained. Clinical results following the in vitro T-lymphocyte depletion of donor bone marrow for the 8 histocompatible and 15 nonhistocompatible bone marrow transplantation are reported. Prompt engraftment with minimal GVHD, despite no posttransplant GVHD prophylaxis, was seen in seven of the matched patients. In the nonhistocompatible bone marrow transplantation, failure of engraftment occurred in 11 patients. Grades III-IV GVHD were seen in two of the four patients that engrafted despite good T-lymphocyte depletion. No predictive correlation could be found between the in vitro analysis of marrow following CT-2 treatment and clinical outcome.

Depletion of T cells from bone marrow for allogeneic transplantation: method for treatment of bone marrow in bulk.

T lymphocytes were depleted from donor marrow for 23 patients undergoing allogeneic bone marrow transplantation using an anti-T-cell antibody, CT-2, and complement. The methodology is described in detail for in vitro depletion of large quantities of bone marrow. The extent of T-lymphocyte depletion using various T-cell markers, the percent of marrow lost in the processing and quantity of antibody, and complement needed are presented. These techniques for in vitro T-lymphocyte depletion were reproducible and did result in an average final yield of 47% of the harvested donor marrow.

Transplantation of HLA-haploidentical T-cell-depleted marrow for leukemia: addition of cytosine arabinoside to the pretransplant conditioning prevents rejection.

A total of 41 patients with hematologic malignancies (other than acute leukemia in relapse) received allogeneic bone marrow transplants at the University of Wisconsin from 1 April 1980 through 31 March 1984. In an effort to minimize graft-versus-host disease, marrow was depleted of T-lymphocytes in vitro with monoclonal anti-T-cell antibody and complement prior to infusion for seven of 19 recipients of marrow from HLA-identical, MLC-nonreactive siblings, and for all 22 recipients of marrow from MLC-reactive HLA-haploidentical donors. The recipients of HLA-identical T-depleted marrow all showed excellent engraftment following standard pre-BMT conditioning with cyclophosphamide and total body irradiation. In contrast, five of five recipients of T-depleted haploidentical marrow failed to engraft following this same conditioning regimen. The addition of cytosine arabinoside to the pretransplant conditioning appeared to correct this problem, allowing engraftment in 14 of 17 subsequent patients. These clinical results, coupled with prior in vitro data, demonstrate the need to adequately suppress residual host-versus-graft immunity in order to prevent the rejection of T-cell-depleted HLA-haploidentical bone marrow.

Relapse of host leukemic lymphoblasts following engraftment by an HLA-mismatched marrow transplant: mechanisms of escape from the "graft versus leukemia" effect.

Leukemic relapses and graft versus host disease (GvHD) remain major complications following allogeneic bone marrow transplantation for leukemia. We present clinical and laboratory details for an eight-year-old boy who received a T-cell-depleted HLA-mismatched marrow transplant as therapy for acute lymphoblastic leukemia (ALL) in second remission. Engraftment with donor marrow was prompt and without any acute GvHD. Nevertheless, the patient's original ALL recurred and proved fatal. The patient remained a chimera with persistent donor lymphocytes present at the time of posttransplant relapse and subsequent to treatment with unsuccessful reinduction chemotherapy. In vitro immune studies showed that these leukemic cells could be recognized and destroyed by the donor's lymphocytes. The relapse itself suggests, however, that the donor's lymphocytes did not effectively destroy the patient's histoincompatible ALL cells in vivo following establishment of the chimeric state. Potential mechanisms are presented to account for this presumed "escape" from the postulated "graft versus leukemia" effect.

Clinical trial depleting T lymphocytes from donor marrow for matched and mismatched allogeneic bone marrow transplants.

Nine patients received T-lymphocyte-depleted histocompatible bone marrow and 28 patients received T-lymphocyte-depleted histoincompatible bone marrow. Eight of nine patients receiving matched bone marrow quickly engrafted without severe graft-versus-host disease (GvHD). None of the eight patients received anti-GvHD prophylaxis medications. Two of these eight patients are currently alive. Nonengraftment and severe GvHD were problems seen in some of the patients given the histoincompatible bone marrow. Additional cytarabine pretransplant permitted engraftment in those patients undergoing histoincompatible transplants for treatment of malignancy, and prednisone and cyclosporine posttransplant reduced the incidence of acute GvHD in those given T-lymphocyte-depleted grafts. Seven of these 28 patients are currently alive. T-lymphocyte-depleted marrow can reduce the occurrence or prevent severe acute GvHD, especially when combined with additional prednisone and cyclosporine; however, the impact on relapse patterns and survival remains to be determined. The occurrence of nonengraftment and treatment-related lymphomas are formidable problems to overcome.

Depletion of T cells from human bone marrow with monoclonal antibody CT-2 and complement.

CT-2 mouse monoclonal antibody to the E-rosette receptor was used with complement to deplete bone marrow of E-rosette-positive cells (T cells). Depletion of E-rosette-positive cells was complete and nontoxic to hematopoietic progenitor cells. Depletion of E-rosette-positive cells with CT-2 may decrease the severity of graft-versus-host disease following bone marrow transplantation and extend the application of bone marrow transplantation to those without HLA-identical donors.

Late recurrences of histiocytic lymphoma after treatment.

Disease-free intervals of 2 to 3 years after treatment of histiocytic lymphoma are generally thought to represent cures; flat survival curves beyond 3 years in several studies support this notion. Four case reports of histiocytic lymphoma recurrences 25, 10, 9 and 6 years, respectively, after the initial diagnosis are presented. Histologic confirmation comparing primary and recurrent disease is presented. The potential biological significance of such patient reports is discussed.

A randomized study of the efficacy of consolidation therapy in adult acute nonlymphocytic leukemia.

The Eastern Cooperative Oncology Group conducted a randomized study to determine the efficacy of consolidation therapy in prolonging the duration of complete remission (CR) in adults with acute nonlymphocytic leukemia (ANLL). Induction chemotherapy with daunorubicin, cytosine arabinoside, and 6-thioguanine (DAT) yielded CR in 65% of 283 patients with ANLL, aged 16-69. For patients aged 60-69, the CR rate was 58%. Of 184 patients in CR, 146 patients were then randomized to receive either maintenance therapy with weekly cytosine arabinoside and 6-thioguanine alone (69 patients) or two courses of reduced doses of DAT 1 mo apart, before commencing the same maintenance program (77 patients). Consolidation therapy resulted in hematologic toxicity, but was not lethal in any of the eligible patients. Patients receiving consolidation plus maintenance therapy experienced a longer CR duration (40 wk) and disease-free survival at 2 yr (28%) than did those patients receiving maintenance therapy alone (34 wk and 14%, respectively). These differences are not statistically significant. These results suggest that approaches to consolidation therapy employing reduced doses of the induction therapy regimen can have, at best, only a small benefit. For consolidation therapy to provide substantial improvement in CR duration, intensive regimens with non-cross-resistant drugs will be required.

The in vivo distribution of indium-111 labeled in vitro alloactivated syngeneic lymphocytes in a patient with relapsed acute myelomonocytic leukemia: implications for adoptive chemoimmunotherapy.

A single patient who had a leukemic relapse six months after receiving a syngeneic bone marrow transplant was given "adoptive chemoimmunotherapy." Lymphocytes from the patients identical twin were alloactivated and grown in T cell growth factor in vitro. After receiving chemotherapy to reduce the number of relapsed leukemia cells, he received 1.1 X 10(10) in vitro alloactivated twin lymphocytes via intravenous and intraperitoneal injections. Although progressive Candidal pneumonia was fatal and prevented analysis of either efficacy or delayed toxicity of this potential form of therapy for this patient, radioactive 111In labelling and scanning showed dissemination of these lymphocytes following either injection route, with no clinical evidence of immediate toxicity.

Pediatric bone marrow transplantation: current progress and future prospects.

Ongoing clinical and laboratory research is being directed at the many problems and complications associated with clinical bone marrow transplantation. The most important goals are to increase the long-term survival of patients receiving bone marrow transplants, decrease the morbidity associated with the process, and extend this therapeutic modality to patients in need of a transplant, but without an HLA identical sibling. In addition, as these problems are resolved, and the toxicity of BMT is controlled, this form of therapy may become the treatment of choice for a number of inherited and acquired hematologic, immunologic, and metabolic disorders that are chronically progressive but ultimately fatal, yet are not now routinely treated with BMT due to the acute morbidity and mortality associated with this major procedure.

HLA identical leukemia cells and T cell growth factor activate cytotoxic T cell recognition of minor locus histocompatibility antigens in vitro.

Lymphocytes from a healthy HLA-identical bone marrow transplant donor were tested for their ability to destroy her brother's acute myelogenous leukemia blasts in vitro. Primary mixed lymphocyte culture (MLC) and cell-mediated lysis (CML) responses between the patient's remission (pretransplant) and donor's lymphocytes were negative. Stimulation of donor lymphocytes for 7 d in vitro with irradiated leukemia cells, leukemia cells plus allogeneic irradiated lymphocytes, or a pool of irradiated lymphocytes from 10 donors, did not activate any cytotoxic cells able to destroy the HLA identical leukemic blasts. Further culturing for 7 additional d in T cell growth factor (TCGF) generated lymphocytes that induced effective cytotoxicity against the leukemic blasts, but not against autologous lymphocytes. Effective killing against the leukemia was observed only in cultures initially stimulated with the irradiated leukemia cells. These cytotoxic cells were maintained in TCGF and mediated persistent killing against the leukemic target cells. They were also able to destroy lymphocytes from the patient's mother and father, but not from an unrelated cell donor. This suggested specific recognition of non-HLA antigens inherited by the patient, that were foreign to the HLA identical bone marrow donor. These lymphocytes were cloned by a limiting dilution technique and one clone maintained cytotoxicity to the AML blasts and the father's lymphocytes, but not lymphocytes from the mother or an HLA-identical donor. This cytotoxicity was inhibited by a monoclonal anti-HLA antibody. Thus, in vitro sensitization of this sibling's lymphocytes with AML blasts followed by TCGF expansion, and cloning, enabled the detection of HLA-restricted cytotoxic cells that recognize minor locus histocompatibility antigens. This immune recognition may be relevant to the "graft vs. leukemia" effect that has been observed in leukemic animals and patients following histocompatible hematopoietic transplants.