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Biomedical subjects

C Nissen

Publications and source records attributed to C Nissen.

At least 91 records · Page 5Linked to original sources

Endogenous megakaryocyte colonies from peripheral blood in precursor cell cultures of patients with myeloproliferative disorders.

Megakaryocyte colony formation, as identified by conventional techniques, was observed in precursor cell cultures from peripheral blood in 8 of 20 consecutive patients with diagnosis of myeloproliferative disease (4/11 patients with polycythemia vera, 3/5 with essential thrombocythemia, 1/2 with primary osteomyelofibrosis and 2 with a myeloproliferative syndrome not further assessable), but not in 50 healthy controls (p less than 0.0001). 7 cultures showed spontaneous erythroid colonies, but were negative for megakaryocyte colonies. Megakaryocyte colony formation was independent of added erythropoietin, plasma or human leukocyte-conditioned medium, but was dependent on the presence of accessory cells. The cells in megakaryocyte colonies had the characteristic morphology of megakaryocytes and stained positively with the IIIa/IIb monoclonal anti-platelet antibody. Thus, megakaryocyte colony formation by precursor cells from peripheral blood in the absence of exogenous stimulating factors seems to be a phenomenon specific for myeloproliferative disease. Differential diagnosis of thrombocythemia may be facilitated by demonstration of endogenous megakaryocyte colony formation, which does not occur in secondary disease.

Cell Nucleus↗

Bone marrow transplantation in Basel: single center experience from 1973 to 1989.

Bone marrow transplantation with a small to medium-sized single hospital team is feasible. It leads to results similar to those observed at large centers and with the same major risk factors: age, stage of the disease at the time of transplant, degree of histocompatibility, graft-versus-host disease prevention method, and selection. A single small to medium-sized center cannot conduct prospective randomized studies but it can pioneer new concepts. Bone marrow transplantation today offers a good choice for patients suffering from otherwise lethal bone marrow diseases. These include severe aplastic anemia, acute leukemias, chronic myeloid and chronic lymphoid leukemia, myelodysplastic syndrome, and congenital disorders. Changes in outcome are due to innovative steps, such as the introduction of CsA for GvHD prevention. In addition they are certainly influenced by unrecognized changes in the patient selection process.

Anemia, Aplastic↗

Misoprostol heals gastroduodenal injury in patients with rheumatoid arthritis receiving aspirin.

High-dose aspirin therapy for rheumatoid arthritis is frequently associated with severe gastrointestinal injury. To explore the possibility of reversing such damage, we conducted a double-blind, multicenter study with misoprostol, a prostaglandin E1 analog, which has demonstrated mucosal protective, gastric antisecretory, and ulcer healing properties. We also studied possible interference of misoprostol with continuing aspirin treatment in the management of patients with rheumatoid arthritis. Patients with confirmed rheumatoid arthritis and endoscopically documented gastroduodenal lesions were randomly assigned to receive 200 micrograms of misoprostol four times a day (123 patients) or placebo (116 patients). Each concurrently received 650 to 1300 mg of aspirin four times a day. After eight weeks of treatment, misoprostol was statistically superior to placebo in healing gastric mucosal injury (70% vs 25%) and duodenal mucosal injury (86% vs 53%). Patients with gastric or duodenal ulcers on admission had superior ulcer healing rates with misoprostol (67% vs 26%). There was no evidence of interference with the antirheumatic properties of aspirin. Mild to moderate adverse experiences were equally noted in misoprostol and placebo groups. Misoprostol, coadministered with aspirin, is well tolerated and highly effective in healing aspirin-associated gastroduodenal lesions in patients with rheumatoid arthritis without altering the therapeutic benefits of aspirin.

Adult↗

A double-blind placebo-controlled comparison of the efficacy and safety of 50, 100, and 200 micrograms of misoprostol QID in the prevention of ibuprofen-induced gastric and duodenal mucosal lesions and symptoms.

Ibuprofen, a commonly proscribed nonsteroidal anti-inflammatory drug that is also available in many countries, including the United States, without a prescription, is known to cause hemorrhage and erosion of the gastroduodenal mucosa. This study was conducted to compare the efficacy of 200, 100, and 50 micrograms of misoprostol and placebo administered qid for 6 days, with a final dose on the morning of the 7th day, in the prevention of gastric and duodenal lesions induced by the concurrent administration of 800 mg of ibuprofen qid. A total of 120 healthy subjects with endoscopically normal gastric and duodenal mucosae were enrolled in the study. The endoscopic examination was repeated 2 h after the final dose on day 7, and the mucosae were graded on a 0 to 4+ scale. In the stomach, all three misoprostol groups were significantly more protective than placebo and did not differ significantly from each other. In the duodenum, the endoscopic scores of the 200- and 100-micrograms misoprostol groups, but not the 50-micrograms group differed significantly from placebo. The 200- and 100-microgram groups did not differ significantly from each other, but both differed from the 50-micrograms group for duodenal mucosal injury. Subjective symptoms thought to be primarily attributable to the NSAID (e.g., pain, indigestion/heartburn and nausea) were recorded by each subject in a diary. Subjects in the 200-micrograms misoprostol group attained the greatest degree of mucosal protection and had a significantly higher incidence of indigestion/heartburn and abdominal pain than the placebo group. One can conclude that misoprostol in both antisecretory (200- and 100-micrograms) and non-antisecretory (50-micrograms) doses protects the gastric mucosa from injury from high anti-inflammatory doses of ibuprofen (3200 mg/day). Only the antisecretory doses (100 and 200 micrograms qid) were effective in the duodenum, suggesting that acid suppression is necessary for mucosal protection to occur in the duodenum.

Adult↗

Allogeneic bone marrow transplantation (BMT) for acquired severe aplastic anaemia (SAA) in children.

The SAA Registry of the EBMT now contains data on 171 children younger than 15 years of age with acquired SAA and undergoing BMT between 1970 and 1988. The overall actuarial survival is 63% at 10 years. In a multivariate Cox analysis, the year of transplant was the most important prognostic factor with a significant advantage for children grafted in 1984-88 (81%) vs 1981-83 (67%) and 1970-80 (41%) (p = 0.02). Cyclosporine A given for GVHD prophylaxis, no treatment before transplant and an interval less than 90 days from diagnosis to BMT were all favourable variables in univariate analysis. As regard to transplant procedures, the better results were obtained using Cyclophosphamide and Cyclosporine A (78%) followed by Cyclophosphamide plus irradiation plus Cyclosporine A (77%). Sex, etiology and the severity of the aplasia had no impact on survival in both uni and multivariate analysis.

Adolescent↗

[Comparative study on in vitro lymphocytotoxicity and mitogenicity of different antilymphocyte globulin (ALG) preparations].

The lymphocytotoxicity and mitogenicity between six different ALG preparations on the clinical use world wide were compared. No significant difference in the lympholytic activity was observed between preparations and 100% cell lysis was achieved at a concentration of 50 micrograms/ml in the presence of complement. On the other hand, four preparations now in use in European countries and USA showed variable mitogenic activities on lymphocytes in the absence of complement, whereas two ALGs used in Japan did not. As the stimulatory effects of ALG on lymphocytes may contribute to the clinical outcome in the treatment of severe aplastic anemia (Kawano et al, 1988), these date can explain the poor clinical results of ALG therapy with those two preparations in Japan. Careful measures should be paid in the construction of treatment protocol and selection of ALG preparations to yield the best results.

Antilymphocyte Serum↗

[Late complications in patients with aplastic anemia].

Of 145 patients with severe aplastic anemia (SAA) treated in Basel from 1976 to 1987, 34 underwent bone marrow transplantation (BMT) and 111 received ALG therapy. We have analyzed the incidence of late complications in both groups of patients. 34 patients treated with ALG developed a hematological complication, 10 a myelodysplastic syndrome (MDS) and 18 paroxysmal nocturnal hemoglobinuria (PNH) associated with clinical symptoms in 12. Two patients had both MDS and PNH. Eight suffered relapse of SAA. After BMT neither of these complications occurred. Most of the non-hematological problems were associated with therapy. In the ALG group androgens were responsible for impotence and gynecomastia in men, deep voice in women and liver tumors in 4 patients. Four other patients developed aseptic necrosis of the hip and one carcinoma of the breast. The most severe late complication after BMT was chronic graft-versus-host disease (GvHD), occurring in patients still receiving methotrexate for prophylaxis of GvHD.

Anemia, Aplastic↗

Abundant macrophage growth in culture from patients with chronic myelogenous leukemia: a risk factor for graft-versus-host disease after bone marrow transplantation.

Peripheral blood cultures of hemopoietic precursor cells from 30 patients with chronic myelogenous leukemia showed different growth patterns before bone marrow transplantation. A strong increase of free and clustered macrophages was seen in 11/30. Of these 11 patients, 10 developed Graft-versus-Host Disease (GvHD). Of 19 patients without the macrophage pattern, 4 developed GvHD (p = 0.004). Of 14 patients with GvHD, 10 had shown the macrophage pattern before bone marrow transplantation, compared to 1/19 without GvHD (p = 0.004). We postulate that excess macrophages in the bone marrow recipient trigger GvHD by enhancing presentation of recipient antigens to donor T-lymphocytes, and that their presence is predictive of GvHD in CML.

Bone Marrow Transplantation↗

Secondary leukemia after severe aplastic anemia.

We describe a patient with acute myeloid leukemia (AML) occurring 5 years after successful treatment of severe aplastic anemia (SAA) with antilymphocyte globulin (ALG). Four years after ALG, SAA had relapsed. A second remission of SAA was achieved, but was followed by transformation of the myelodysplastic syndrome into overt AML. After 2 courses of high-dose cytosine arabinoside and VP-16 complete remission occurred. This case shows that chemotherapy of secondary leukemia after SAA is feasible, and that ex-aplastic bone marrow is capable of complete recovery from chemotherapy-induced aplasia. Morphological anomalies of bone marrow noticed early during remission of SAA might predict a late transformation in leukemia.

Adolescent↗

Testosterone reduces complement sensitivity of precursor cells in aplastic anaemia patients treated with antilymphocyte globulin.

Of 53 consecutive patients with aplastic anaemia who were re-examined at various intervals after treatment with antilymphocyte globulin, 30 had sufficient bone marrow colony forming capacity to permit evaluation of androgen effects in vitro. In 22 patients, precursor cells of the myeloid and erythroid line were abnormally sensitive to a preincubation in isosmolar sucrose with 5% fresh autologous serum compared to heat-inactivated autologous serum. This phenomenon was interpreted as excess complement sensitivity. This inhibitory effect of fresh serum in the bone marrow sucrose test was abrogated by addition of 10(-6) M testosterone to the preincubation phase in 15 of the 22 patients. In six of these 15, 10(-7) M dexamethasone had a similar effect; in the other nine patients only testosterone rendered the bone marrow sucrose test negative. This effect of testosterone on colony growth was indirect, since addition of 10(-9)-10(-5) M testosterone to primary bone marrow cultures from the same patients had no effect. We propose that testosterone in these experiments interacted with the complement system. In patients who have complement sensitive precursor cells, androgens might thus prevent complement mediated lysis of haemopoietic cells to some extent. The test described could help identification of patients in autologous bone marrow remission who are likely to benefit from androgen treatment.

Adolescent↗

Late haematological complications in severe aplastic anaemia.

137 patients with severe aplastic anaemia (SAA) were treated in Basel from 1976 to 1986. 34 underwent bone marrow transplantation (BMT) and 103 received antilymphocyte globulin (ALG) therapy. We have analysed the incidence of late haematological complications in both groups of patients. 20 patients treated with ALG developed a late haematological complication. A myelodysplastic syndrome or frank leukaemia occurred in eight and paroxysmal nocturnal haemoglobinuria (PNH) in 13 patients. Nine of the 13 patients with PNH had clinical signs of haemolysis, four only had positive laboratory tests. One patient had PNH and acute leukaemia. The risk of developing a haematological complication increased continuously and reached 57% at 8 years. Neither PNH nor leukaemia occurred in patients treated with BMT. The increased survival rate and the long observation time after ALG therapy have revealed a new perspective of the prognosis of aplastic anaemia. Patients treated with BMT appear to be cured whereas those treated with ALG remain at risk for late complications.

Adolescent↗

Bone marrow transplantation (BMT) versus immunosuppression for the treatment of severe aplastic anaemia (SAA): a report of the EBMT SAA working party.

This is an analysis of 509 patients with severe aplastic anaemia (SAA) treated in Europe between 1981 and 1986; 218 patients were treated by allogeneic bone marrow transplantation (BMT) from HLA identical sibling donors and 291 with immunosuppressive therapy (IS) with antilymphocyte globulin (ALG). The overall actuarial survival was 63% after BMT and 61% after IS therapy at 6 years. All patients fulfilled the criteria of SAA; however, most patients with a neutrophil count of less than 0.2 x 10(9)/l also had infections and haemorrhages. Therefore a further subclassification was defined by pretreatment peripheral blood neutrophil count: very severe aplastic anaemia (vSAA) (less than 0.2 x 10(9)/l neutrophils) and moderately severe aplastic anaemia (mSAA) (0.2-0.5 x 10(9)/l neutrophils). A Cox regression analysis showed that the only significant pre-treatment variables were a low neutrophil count (P = 0.001) and increasing age (P = 0.05). Thus it seemed reasonable to analyse survival data after combined stratification for neutrophils (vSAA versus mSAA) and age (cut off at 20 years). BMT was superior to IS in patients with vSAA under 20 years of age (64% v. 38%; P = 0.01). IS was superior to BMT in patients with mSAA aged 20 or more (82% v. 62%; P = 0.002). The two treatments gave comparable results in young patients with mSAA (BMT = 58%, IS = 62%; P = 0.1), and in older patients with vSAA (BMT = 44%, IS = 43%; P = 0.06). Overall 75/218 and 87/291 patients, given BMT or IS respectively, died. The major cause of failure in BMT patients was graft rejection (n = 22) or problems associated with graft-versus-host disease. For ALG patients the major problem was persistence of the aplasia with haemorrhage (n = 32) or infections (n = 46). This study indicates that over 60% of patients with SAA can be successfully treated with either BMT or IS. Overall survival does not differ in the two groups, though significant differences emerge after stratification for severity of the aplasia and age.

Adolescent↗

Immunostimulatory effects of different antilymphocyte globulin preparations: a possible clue to their clinical effect.

Antilymphocyte globulin (ALG) and antithymocyte globulin (ATG) have an established role in the treatment of severe aplastic anaemia. The response rate ranges from 40% to 80%. Its mode of action is believed to be complement dependent lysis of immunocompetent cells which inhibit haemopoietic maturation. This might not be the sole mechanism. We have tested four different preparations of ALG/ATG for their mitogenic effect on normal peripheral blood cells and on enriched T-cells in vitro by 3H-thymidine incorporation. We found marked differences between the four preparations. One was strongly mitogenic and able to induce profound release of haemopoietic growth factors. This mitogenic effect could be detected in the serum of patients during ALG treatment. Clinical response rates of this preparation are about 80%. Three other preparations were of lower or no stimulatory effect. Clinical response rates with these preparations vary between 40% and 60%. From our results, we postulate that the beneficial effect of ALG could be partially due to its ability to stimulate release of haemopoietic growth factors. The mitogenicity of different ALG/ATG preparations should be tested as an in vitro parameter of clinical efficacy.

Adjuvants, Immunologic↗

Repair of UV-induced DNA damage in aplastic anaemia: changes after treatment with antilymphocyte globulin (ALG).

The extent of DNA-repair induced by UV-C irradiation was measured in peripheral unstimulated lymphocytes of 24 patients with aplastic anaemia at different stages of disease and compared with the results obtained in 92 controls. As parameter of the DNA-repair synthesis, the incorporation of (3H)thymidine in the presence of 2 mmol/l hydroxyurea (HU) was taken. Of 19 patients tested after treatment with antilymphocyte globulin (ALG), 5 were in complete autologous haemopoietic remission, defined as greater than 1000 granulocytes/mm3, greater than 100,000 platelets/mm3 and a nontransfused haemoglobin value greater than 10 g%. 14 patients were in partial remission, defined as improvement of haemopoietic function, not meeting the criteria for complete remission. 4/5 patients in complete remission had normal DNA-repair synthesis, compared to 4/14 patients in partial remission. In 92 controls, a normal level was found in 70 cases. In 4/5 patients examined at diagnosis and at various intervals after ALG-treatment, DNA-repair synthesis was low at diagnosis. It increased after therapy and paralleled improvement of haemopoietic function to some extent. It is suggested that in aplastic anaemia there are different populations of lymphocytes with differing DNA-repair capacity; ALG treatment seems to favour expansion of the normal population, which is associated with improvement of haemopoietic function.

Adolescent↗

Necrotizing tracheobronchitis following high-frequency ventilation: effect of lung deflation.

A piglet model of acute respiratory failure was used to determine whether necrotizing tracheobronchitis (NTB) reported during high-frequency pneumatic flow interrupter (HFFI) ventilation could be minimized by a different ventilatory strategy. Twenty-one piglets (mean age 3.8 days, average weight 1.4 kg) were anesthetized with ketamine and given Pavulon prior to saline lung lavage. Femoral vessels were cannulated for measurements of blood pressures, arterial blood gases (ABG), and fluid administration. Airway pressures were measured 5 mm above the endotracheal tube tip. To allow for lung deflation, HFFI (10 Hz) was programmed to pause for 1 sec either 5 (HFFI5) or 12 times per min (HFFI12). Seven animals were assigned to each of the treatment groups and to a conventional mechanical ventilation (CMV) control. All animals were kept on 1.0 FIO2 with ventilators adjusted to maintain ABG (pO2 = 50-100 mmHg and pCO2 = 30-40 mmHg). After 6 h of ventilation, the animals were sacrificed and their lungs inflated with formalin to 40 cm H2O. Sections were obtained from trachea, carina, mainstem, and hilar bronchi. An airway injury score (AIS) was calculated after "blinded" microscopic evaluation. There was no difference in total AIS between CMV (2.4) and HFFI12 (8.6) but a statistically significant difference (p less than 0.05) existed between CMV and HFFI5 (14.1). NTB was limited to the trachea during HFFI12 but extended down to the hilar bronchi during HFFI5. More frequent lung deflations reduce the severity and distribution of NTB during HFFI ventilation.

Animals↗