Characterisation of kilo electron volt neutron fluence standard with the 45Sc(p,n)45Ti reaction at NMIJ.

We are developing a national standard of a monoenergetic kilo electron volt neutron field with the (45)Sc(p,n)(45)Ti resonance reaction. A wide resonance yields 27.4 keV neutrons at 0 degrees with respect to the proton beam. The proton energy was precisely determined in the measurement of the relative neutron yield as a function of the proton energy from the threshold energy to 2.942 MeV. Absolute measurement of the monoenergetic neutron fluence was performed using a (3)He proportional counter. Relative measurement was also carried out using a Bonner sphere calibrated at our 144 keV standard neutron field. Calibration factors were obtained between the count of a neutron monitor and the neutron fluence. A silicon-surface barrier detector with a (6)LiF foil converter was also being developed for the neutron fluence measurement. Successful results were obtained in the tests in the 144 keV standard neutron field.

Development of the fast neutron standard using a Be({alpha},n) reaction at the National Metrology Institute of Japan.

This paper describes the 8-MeV neutron field where the neutrons are generated in the (9)Be(alpha,n)(12)C reaction by bombardment of a beryllium target with a 2.4-MeV (4)He(+) beam from a Van de Graaff accelerator. The neutron field is being prepared for a new national standard on neutron fluence in Japan. Absolute measurement of the neutron fluence was taken using a proton recoil neutron detector, consisting of a silicon surface barrier detector with a polyethylene radiator. Neutron spectra were measured using a newly developed recoil proton spectrometer and a liquid organic scintillation detector. The gamma rays existing in the field were also characterised using a liquid organic scintillation detector. The ambient dose equivalents of the gamma rays were estimated to be <100 microSv at the neutron fluence of 10(7) neutrons cm(-2).

Liver function tests of recipients with hepatitis C virus infection after bone marrow transplantation.

We used the polymerase chain reaction (PCR) to determine the presence of hepatitis C virus (HCV)-RNA in serum samples obtained from 19 patients with leukaemia or severe aplastic anaemia and investigated the correlation between HCV status and the results of liver function tests after bone marrow transplantation. PCR analysis of serum samples obtained before transplant showed that 10 of 18 patients were HCV-RNA-positive; 5 of these patients had developed acute post-transfusion hepatitis 1-11 months before transplant. An additional patient was HCV-RNA-positive on post-transplant day 62. Eight HCV-RNA-positive patients had pre-transplant GPT levels above the upper limit of normal. In these patients the GPT decreased significantly from a median of 104 IU/l (54-822 IU/l) pre-transplant to 23 IU/l (15-56 IU/l) on post-transplant days 8-12. In 9 of 11 HCV-RNA-positive patients, the GPT increased transiently from days 40 to 50 and again increased after day 100. Two of these patients died from hepatic failure; the GPT levels normalised in 3 patients after day 300 but continued to fluctuate in 4 patients. In the remaining 2 HCV-RNA-positive patients, the GPT remained close to the normal range throughout the follow-up period. Three HCV-RNA-positive patients became HCV-RNA-negative after 1-3 years. In these patients, the GPT remained normal for > 3 years after day 300.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of chimerism after bone marrow transplantation with single locus minisatellite DNA probes.

The origin of cells in almost all allogeneic donor-recipient pairs can be determined through the use of highly polymorphic minisatellite DNA probes. Single-locus probes were cloned from hypervariable fragments in a human DNA fingerprint detected with a multi-locus probe. While each probe is highly polymorphic and locus specific, they all contain repetitive sequences. The properties of single-locus probes have improved the sensitivity of detecting mixed chimerism in comparison with multi-locus probes. The use of single-locus probes permitted detection of mixed chimerism (MC) at levels as low as 0.625%, approaching that obtained by PCR methods. In the present study, five patients who received allogeneic BMT for hematologic malignancies were analyzed. Two patients exhibited MC after BMT. One developed acute GVHD and chronic GVHD and remained in CR while the second patient who had no signs of GVHD suffered a relapse.

Donor-HLA-incompatible marrow transplantation with an anti-donor cytotoxic antibody in the serum of the patient.

A 42-year-old female with acute mixed lineage leukemia received a marrow transplantation from an HLA non-identical sibling. The serum of the patient showed a positive crossmatch for anti-donor lymphocytotoxic antibody and exhibited a complement-mediated cytotoxicity to donor hematopoietic progenitor cells. In an attempt to reduce the risk of graft rejection, a large volume plasma exchange was performed, which was followed by an infusion of irradiated donor lymphocytes to eliminate remaining antibodies from her serum. The level of anti-donor antibody fell below the sensitivity of the anti-human immunoglobulin lymphocytotoxicity test after the infusion of donor lymphocytes. The cytotoxic activity against donor progenitor cells also disappeared from the serum. Cyclosporin had been administered for 2 weeks before marrow infusion, and methylprednisolone and prednisolone for 1 week before the initiation of conditioning chemoradiotherapy. Conditioning comprised cytosine arabinoside 5.6 g/m2, cyclophosphamide 4500 mg/m2 and fractionated total body irradiation with 15 Gy followed by an infusion of 4.0 x 10(8) cells/kg of unmodified marrow cells. Engraftment of donor cells was documented by HLA typing of peripheral lymphocytes. A sustained engraftment may be obtained in a donor-incompatible HLA non-identical marrow transplantation with anti-donor antibody by elimination of the antibody and achieving an intensive immunosuppression in the recipient before marrow infusion.

Diagnostic value of hemostatic parameters in bone marrow transplant-associated thrombotic microangiopathy.

We investigated hemostatic parameters in a prospective study of 16 patients who received bone marrow transplants (BMT). We found a significant rise in the levels of fibrinogen, plasmin-alpha2 antiplasmin inhibitor complex, tissue-plasminogen activator.plasminogen activator inhibitor complex (t-PA.PAI), von Willebrand factor antigen, and thrombomodulin on day 14 after transplant compared with values before transplant. Protein C and thrombin-antithrombin III levels did not change significantly. No significant changes in prothrombin time ratio, activated partial thromboplastin time, or protein S were detected. Patients who had grades II-IV graft-versus-host disease (GVHD) (n = 6) showed a significantly higher level of t-PA.PAI on day 14 compared with those with grades 0-I GVHD (n = 10) (P = 0.0062). Three patients with grades II-IV GVHD developed thrombotic microangiopathy (TMA) on days 19, 19 and 62. In these patients, we noted significantly lower levels of fibrinogen (P = 0.0383), and significantly higher levels of t-PA.PAI (P = 0.0008) and thrombomodulin (P = 0.0001) on day 14 compared with those patients who did not develop TMA. These results suggest that prothrombotic states and endothelial damage may be caused by the conditioning regimen and/or acute GVHD during BMT; thrombomodulin values on day 14 post BMT may be useful in surveillance for TMA because of endothelial cell injury.

Predicting relapse of chronic myelogenous leukemia after allogeneic bone marrow transplantation by bcr-abl mRNA and DNA fingerprinting.

Fourteen patients treated by allogeneic bone marrow transplantation for chronic myelogenous leukemia (CML) were evaluated by the polymerase chain reaction (PCR) for bcr-abl-specific transcripts. Nine patients were transplanted in the first chronic phase, three in the second chronic phase, and two in the accelerated phase. All patients achieved a complete cytogenetic and hematologic remission after bone marrow transplantation. Twelve patients are alive (median, 18 months; range, 5-54 months) and two patients died early. bcr-abl mRNA was persistently detectable for 6 to 54 months in four patients (patients 1, 3, 4, 6). From two of them, DNA fingerprint analysis showed only donor type DNA although bcr-abl mRNA was detectable. bcr-abl mRNA was never detectable posttransplant in three patients (patients 2, 5, 13). Six patients had detectable bcr-abl mRNA (patients 8-12, 14): by 6 months, all of these patients were bcr-abl mRNA negative. One patient (patient 7) had detectable full bcr-abl mRNA again at 12 months, but was then negative at 20 months. Ten patients (patients 2, 4-8, 10-13) had never detectable Philadelphia (Ph1) chromosome t(9.22) translocation, whereas four patients had detectable Ph1 (patient 1, 3, 9, 14); by 6 months, three of four cases were negative. One patient (patient 1) had detectable Ph1 at 44 months, but was negative at 50 months. Three of six patients who initially had bcr-abl mRNA detectable posttransplant (patient 7-9) became negative for bcr-abl mRNA at the time of development of chronic graft-versus-host disease (GVHD). These results suggest that the detection of subclinical Ph1 positive cells by PCR is not associated with imminent clinical or cytogenetic relapse. Moreover, graft-versus-leukemia (GVL) activity may contribute to the treatment of minimal residual disease in CML after allogeneic bone marrow transplantation.

Acute minimally differentiated myeloid leukemia (M0) with inv(3)(q21q26).

We describe a 55-year-old Japanese man with acute minimally differentiated myeloid leukemia (M0) with an inversion in the long arm of chromosome 3, i.e., inv(3)(q21q26). Patients with this chromosomal abnormality usually show normal or elevated platelet counts. However, our case had a low platelet count with megakaryocytic dysplasia at diagnosis. Furthermore, the 3q21q26 aberration is generally detected in patients with acute myelogenous leukemia (AML) or myelodysplastic syndrome. To the best of our knowledge, it has also been reported in two cases of AML-M0 with 3q21q26 and this is the third case of AML-M0 with 3q21q26. Thus it is suggested that there is some relationship between this type of karyotype abnormality and leukemogenesis and/or thrombopoiesis.

Residual leukemic cell counts in the bone marrow at the end point of intensive induction therapy may be a prognostic factor for acute myeloblastic leukemia in adults.

Between January 1990 and May 1994, 59 previously untreated adult patients with acute myeloblastic leukemia (AML) were treated with a combination of behenoyl-cytosine-arabinoside (BHAC), daunorubicin (DNR), 6-mercaptopurine (6-MP) and prednisolone (PSL). Forty one patients (69.5%) achieved complete remission (CR). The Kaplan-Meier analysis revealed an actuarial probability for remaining in remission of 36% in patients who achieved remission and a survival of 29% in all patients at 5 years. A favorable factor relative to achieving CR was performance status (P=0.04). In addition the presence of 300 cells/microl or less of residual leukemic cell counts in the bone marrow at the end point of induction therapy tended to favor remission (P=0.06) using the multivariate analysis with a multiple logistic regression model. In addition the residual leukemic cells counts of less than 300/microl in the bone marrow at the end point of induction therapy was the most significant factor for durable remission (P=0.05) by the Cox's proportional hazard model. We concluded that residual leukemic cells counts in the bone marrow at the end point of intensive induction therapy is a valuable prognostic factor for adults receiving response-oriented individualized induction therapy for AML.

Predictive factors for central nervous system involvement in non-Hodgkin's lymphoma: significance of very high serum LDH concentrations.

Factors predictive for central nervous system (CNS) involvement at presentation were investigated in 152 patients with non-Hodgkin's lymphoma (NHL) except for lymphoblastic cell lymphoma and small noncleaved cell lymphoma. Twelve patients developed CNS involvement during their disease course. The incidence was 7.9% of all the patients studied and 17.0% of the patients with serum LDH concentration > or = two times the upper limit of normal (2N). By univariate analysis, stage IV disease (P = .023), a serum LDH concentration > or = 2 N (P = .009), and bone marrow involvement (P = .016) were risk factors for CNS involvement. Multivariate logistic regression analysis identified a serum LDH concentration > or = 2 N (P = .032) as an independent predictor for CNS involvement. All 12 patients who developed CNS involvement were among the 126 patients with diffuse lymphoma, whereas none of the 17 patients with follicular lymphoma developed CNS involvement, although the difference was not statistically significant. The median survival of the patients with CNS involvement was only 4.5 months. We conclude that a serum LDH concentration > or = 2N at presentation is a significant predictive factor for CNS involvement for NHL patients without lymphoblastic lymphoma and small noncleaved cell lymphoma. Therefore, we would suggest that CNS prophylaxis should be considered for patients with a serum LDH concentration > or = 2N at presentation and diffuse lymphoma once a complete remission is achieved.

Variant of intron 22 inversions in the factor VIII gene in severe hemophilia A.

Recurrent DNA inversions, which disrupt the factor VIII (FVIII) gene, generally occur between a region of intron 22 (int22h) and one of two homologous copies of this region, located 300 to 400 kb telomeric to the FVIII gene. This report describes a patient with severe hemophilia A and a high level inhibitor with atypical hybridization patterns. A Bcl I Southern blot assay was altered to 17.5, 16, and 14 kb. His mother and two out of four aunts tested had normal and abnormal restriction patterns which led to a total of five different fragments, suggesting that they were carriers. The Xba I plus Kpn I restriction fragment-length polymorphism in intron 22 by Southern blotting using the same probe (probe a) yielded the 6.2 kb polymorphic band, with a clearly separated 6.6 kb band from the non-factor VIII region; an alternative int22h hybridization probe (probe x) detected no additional fragment. These results suggest that probe a as well as probe x could recognize an intron-22-sized fragment. This report shows a variation in the number of int22h copies although we could not find the inversion junction.

Chronic myelomonocytic leukemia with t(1;3)(p36;q21) and a synchronous gastric cancer.

The translocation t(1;3)(p36;q21) has been reported previously in patients with the myelodysplastic syndrome and with acute nonlymphocytic leukemia. It has been reported in only 5 cases of chronic myelomonocytic leukemia and t(1;3)(p36;q21). We observed a case of chronic myelomonocytic leukemia with t(1;3)(p36;q21) complicated by a gastric cancer at the time of diagnosis.

Case report: inhalation therapy of paromomycin is effective for respiratory infection and hypoxia by cryptosporidium with AIDS.

A 24-year-old man with AIDS and hemophilia A had intractable diarrhea and fever. Upon examination of stool and of a sigmoidal biopsy specimen, cryptosporidium was revealed. Approximately 2 months after admission, respiratory infection with hypoxia due to cryptosporidium developed. Paromomycin inhalation was effective therapy. To the authors' knowledge, this is the first case of respiratory cryptosporidiosis treated successfully by paromomycin inhalation.

Case report: fulminant hepatitis C viral infection after allogeneic bone marrow transplantation.

The authors describe two patients with acute leukemia who died of fulminant hepatitis caused by hepatitis C virus (HCV) after an allogeneic bone marrow transplant, the first such cases reported in Japan. Both had developed posttransfusion hepatitis during chemotherapy to induce remission and for consolidation. Six months after blood transfusion, the blood serum of each patient was positive for HCV antibody and HCV RNA. In each case, there was a transient improvement in liver function after the transplant. However, within 5 months of receiving the transplant and coincident with the withdrawal of cyclosporin A, each patient developed an acute exacerbation of hepatitis. The fulminant hepatitis in our patients may, therefore, have been caused by the reactivation of HCV induced by the immunosuppressive therapy followed by a reconstitution of the immune system.

Torsades de pointes complicating pentamidine therapy of Pneumocystis carinii pneumonia in acute myelogenous leukemia.

Pentamidine isethionate induced torsades de pointes in a 33-year-old woman with acute myelogenous leukemia. This is the first report of Pentamidine-induced torsades de pointes in Japan for over ten years. On the 4th day of intravenous pentamidine for Pneumocystis carinii pneumonia, asymptomatic sinus bradycardia was noted with QT interval prolongation, and torsades de pointes were revealed on the 8th day. Although torsades de pointes was dissolved with discontinuation of the intravenous pentamidine and administration of magnesium sulfate, sinus bradycardia and prolonged QT interval persisted. Ventricular pacing resulted in no arrhythmia and normalization of the QT interval on the 10th day after discontinuation of pentamidine. Careful monitoring of the electrocardiogram should be carried out during intravenous pentamidine therapy.

Characterization of gamma rays existing in the NMIJ standard neutron field.

Our laboratory provides national standards on fast neutron fluence. Neutron fields are always accompanied by gamma rays produced in neutron sources and surroundings. We have characterised these gamma rays in the 5.0 MeV standard neutron field. Gamma ray measurement was performed using an NE213 liquid scintillator. Pulse shape discrimination was incorporated to separate the events induced by gamma rays from those by neutrons. The measured gamma ray spectra were unfolded with the HEPRO program package to obtain the spectral fluences using the response matrix prepared with the EGS4 code. Corrections were made for the gamma rays produced by neutrons in the detector assembly using the MCNP4C code. The effective dose equivalents were estimated to be of the order of 25 microSv at the neutron fluence of 10(7) neutrons cm(-2).

Development of a fast neutron spectrometer composed of silicon-SSD and position-sensitive proportional counters.

A new fast neutron spectrometer has been developed. The spectrometer is composed of a silicon surface barrier detector and three position-sensitive proportional counters with methane gas working as counting gas and a radiator. A collimated incident neutron interacts with a hydrogen atom in the methane gas to generate a recoil proton. The position information on the path of the recoil proton obtained from the three position-sensitive proportional counters gives the recoil angle. In the meanwhile, the energy of the recoil protons is measured with the three proportional counters and the silicon surface barrier detector. The characteristics of the spectrometer were evaluated with a monoenergetic neutron beam. The best energy resolution was 1.8% for 5.0 MeV neutrons.

Development of a tiny neutron probe with an optical fibre for BNCT.

We have developed a tiny neutron probe detector as a monitor of a thermal neutron flux for boron neutron capture therapy. The detector consists of an optical fibre and a small neutron probe. We have used a film-like ZnS(Ag) scintillator and a 6LiF neutron converter for the neutron probe. In order to improve the gamma-neutron discrimination ability, vacuum evaporation of 6LiF onto the ZnS(Ag) film has been done. In order to improve the neutron detection efficiency, we made use of a wavelength-shifting fibre as the probe material. The characteristics of the above two types of fibre probe detector have been evaluated experimentally.

[CT findings and surgical treatment of atlanto-axial rotatory fixation: a case report].

A case of atlanto-axial rotatory fixation (AARF) was presented in a 19-year-old female who developed sudden onset of neck pain and limitation of neck movement after direct carotid angiography for seizure disorder. Neurological examination was negative except for cock-robin posture and mild hypesthesia and hypalgesia in left C2 distribution. Plain films of the cervical spine disclosed abnormal alignment of C1-C2 and possible rotational dislocation. Bilateral selective vertebral angiography showed marked anterior and posterior displacement of left and right vertebral artery, respectively, at the level of C1. On CT metrizamide myelography, there was clockwise rotation of C1 on C2 with locked facet on the left but no evidence of cord compression was found. With diagnosis of AARF, manual reduction under general anesthesia and with fluoroscopic control was first attempted without success. Therefore, the patient underwent open reduction by using high speed air-drill and posterior fusion of C1 to C3 with acryl and wire. Postoperative course was uneventful and the patient went back to work as a computer operator in three months. The etiology of AARF was described by many authors, but in our case, congenital hypogenesis of transverse and alar ligaments plus minor trauma was most suggested. For neurological manifestations of AARF, occipital neuralgia, headache, neck pain, limitation of neck movement and cock-robin posture were reported, but the cock-robin posture was most characteristic and was an important symptom for the early diagnosis. In neuroradiological findings of AARF, plain CT and CT metrizamide myelography are very useful. Because they clearly demonstrate the degree of rotation and interlocking of atlanto-axial joints, and the presence of cord compression.

[p53 tumor suppressor gene mutation and prognosis in 105 cases of bladder cancer--the relationship between mutation of the p53 gene with clinicopathological features and smoking].

PURPOSE: Alterations of the p53 tumor suppressor gene are the most common genetic change detected in human cancers. The incidence of p53 gene mutation in bladder tumor patients were studied and were compared with clinicopathological findings, smoking history and prognosis. MATERIALS AND METHODS: Polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) was used for analysis from exon 4 to 9 of p53 gene in 105 cases of primary bladder tumors. RESULT: p53 matations were detected in 38 or 105 patients (36.2%). Kaplan-Meier Survival curves fo groups wit or without p53 gene mutation show a statistically significant difference (p = 0.0098). The mutation of p53 gene in stages pT 1 pT 1. pT 2, pT 3, pT 4 was found in 2 of 12 (16.7%), 8 of 32 (25.0%), 10 of 25 (40.0%), 12 of 20 (60.0%), 6 of 16 (37.5%) and in grades I, II, III, was noted in 1 of 17 (5.9%), 16 of 49 (32.7%), 21 of 39 (53.8%) cases, respectively. Significant differences were found for groups with grade I and grade II-III (p = 0.0045) cancers and in cases of superficial (stage pTa-1) and muscle-invasive (pT 2-4) tumors (p = 0.0148). However, mutation of p53 was not related to either age or sex in 105 patients. Recurrence rates in stage pTa-1 superficial tumor group with or without p53 mutation showed a statistically significant difference (p = 0.0419). No statistically significant difference was noted between p53 mutation and habitual smoking as well as durations of smoking. CONCLUSIONS: p53 mutations occur more commonly in higher grades and later stages of bladder tumors. Our results suggest that the prognostic factor is linked to not only histological findings but also to the presence of p53 mutation. The mutations of the p53 gene may be involved in the late events of tumorigenesis and might be used as good molecular markers for prognosis in bladder tumor.