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It was shown that, without computational fluid dynamics, intergranular liquid feeding in the mushy zone during welding of an alloy can still be calculated using an analytical model. The intergranular channel was approximated as a round pipe whose radius varies with the fraction of solid fS, which in turn varies with temperature T. The model was applied to 2014 Al (∼Al-4.4Cu) and 5086 Al (∼Al-4.0Mg) to compare their susceptibility to solidification cracking. Based on the extent of the liquid pressure drop caused by intergranular liquid flow, the contribution to the crack susceptibility by transverse tension was compared to that by solidification shrinkage.

It was shown that, without computational fluid dynamics, intergranular liquid feeding in the mushy zone during welding of an alloy can still be calculated using an analytical model. The intergranular channel was approximated as a round pipe whose radius varies with the fraction of solid fS, which in turn varies with temperature T. The model was applied to 2014 Al (~Al-4.4Cu) and 5086 Al (~Al-4.0Mg) to compare their susceptibility to solidification cracking. Based on the extent of the liquid pressure drop caused by intergranular liquid flow, the contribution to the crack susceptibility by transverse tension was compared to that by solidification shrinkage.

It has been demonstrated that the susceptibility to solidification cracking can be calculated based on the index of |dT/d(fS)1/2| (T: temperature; fS: fraction solid) near the end of solidification. To distinguish the role of transverse tension verse that of solidification shrinkage in solidification cracking, however, computational fluid dynamics was used to calculate the flow of the intergranular liquid towards the roots of columnar dendritic grains using arc welding of Al–Cu alloys as an example. The calculated results show the solidification shrinkage dominates crack formation at the strain rate of 0.0001/s, but transverse tension dominates at the strain rate of 0.1/s. In between, both solidification shrinkage and transverse tension can play a significant role.

It has been demonstrated that the susceptibility to solidification cracking can be calculated based on the index of |dT/d(fS)1/2| (T: temperature; fS: fraction solid) near the end of solidification. To distinguish the role of transverse tension verse that of solidification shrinkage in solidification cracking, however, computational fluid dynamics was used to calculate the flow of the intergranular liquid towards the roots of columnar dendritic grains using arc welding of Al–Cu alloys as an example. The calculated results show the solidification shrinkage dominates crack formation at the strain rate of 0.0001/s, but transverse tension dominates at the strain rate of 0.1/s. In between, both solidification shrinkage and transverse tension can play a significant role.

ABSTRACTSolidification cracking can occur when neighbouring columnar grains are separated by tensile strain perpendicular to the grain boundary. In this study, a method to determine the tensile strain causing solidification cracking in welding was developed. A two-dimensional model was built to calculate the tensile strain perpendicular to the grain boundary during solidification, considering heat transfer, stress and strain evolution. The grain boundary direction was determined by calculating the temperature gradient and then the tensile strain causing solidification cracking was obtained by calculating the strain in the direction perpendicular to the grain boundary using strain transformation rule. This method to determine tensile strain causing solidification cracking can provide reference for future numerical and experimental studies on solidification cracking.

Solidification cracking can occur when neighbouring columnar grains are separated by tensile strain perpendicular to the grain boundary. In this study, a method to determine the tensile strain causing solidification cracking in welding was developed. A two-dimensional model was built to calculate the tensile strain perpendicular to the grain boundary during solidification, considering heat transfer, stress and strain evolution. The grain boundary direction was determined by calculating the temperature gradient and then the tensile strain causing solidification cracking was obtained by calculating the strain in the direction perpendicular to the grain boundary using strain transformation rule. This method to determine tensile strain causing solidification cracking can provide reference for future numerical and experimental studies on solidification cracking.

No relevant conflicts of interest to declare.

To determining the clonal origin of dysplatic cells in Myelodysplastic syndromes (MDS) .Karyotypic analyses of bone marrow cells using R-banding technique were carried out to determine the chromosomal abnormalities. Interphase fluorescence in situ hybridization (FISH) and morphologic analysis of bone marrow aspirates were performed in the same cells to investigate the clonal origin of dysplatic cells in 8 MDS patients.All patients had clonal karyotypic abnormalities: simple abnormality in 1 patient, complex abnormalities in 6 patients, coexistent of two unrelated clones in 1 patient. Most of dysplastic cells in 7 of 8 MDS patients derived from neoplasia clone while 1 patient had a reverse result,no matter what cell lineage was involved. Some of non-dysplastic cells of all patients derived from malignant clone; in 7 patients, the proportion of dysplastic cells in malignant clone were significantly higher than that of non- malignant clone.Most of dysplastic cells in MDS derived from malignant clones, while the minority of them derived from non-malignant clones. Thus, it is reasonable to expect that in most cases myelodysplasia is present in malignant clone and can be taken as an important diagnostic evidence for MDS.No relevant conflicts of interest to declare.

No relevant conflicts of interest to declare.

Abstract 4864

Abstract 4858

To verify whether CpG-oligodeoxynucleotide (CpG-ODN) can raise the detection rate of the karyotypic abnormalities in chronic lymphocytic leukemia (CLL).The bone marrow (BM) or peripheral blood (PB) cells from 57 cases of CLL were collected and cultured with CpG-ODN DSP30+interleukin-2 (IL-2), phytohemagglutinin (PHA), pokeweed(PWM) or IL-2, respectively. 5 days later cells were harvested for chromosome preparation. Karyotypic analysis was performed using R banding technique. Panel fluorescence in situ hybridization (FISH) was carried out on 19 cases of CLL with normal karyotype using following probes: Cen12, D13S25, Rb1, ATM, P53, MYB and IgH. Genomic DNA from 21 cases of them was extracted from BM or PB. The immunoglobulin variable heavy chain (IgVH) were amplified by polymerase reaction (PCR) and sequenced. CD38 and ZAP70 expressions in leukemic cells were determined by flow cytometry (FCM).The detection rate of karyotypic abnormalities in CpG-ODN+IL-2 group (43.85%) was obviously higher than PHA (15.09%), PWM (17.31%) and IL-2 (3.13%) groups (P<0.01). 52 karyotypic abnormalities were found. Among them, trisomy12 (+12) or +12 with other abnormalities were the most common, while translocations were the most frequent structural abnormalities including 3 unbalanced and 11 balanced translocations among which 7 had 14q32 rearrangements. 13 cases showed one or more abnormalities on FISH examination including trisomy12 and P53 deletion each in one case, IgH rearrangement and partial deletion each in one case, 13q14.3 deletion in 11 cases of which 5 cases also had Rb1 deletion, one case had Rb1 partial deletion. No cases with ATM or MYB deletions were found. IgVH mutation was detected in 10/21 cases by PCR and sequencing. FCM showed 10/45 cases expressed CD38, while 11/27 cases expressed ZAP70. Among 26 cases examined for CD38 and ZAP70 expressions simultaneously, 5 cases were CD38+ZAP70+, 13 cases CD38-ZAP70-, 6 cases CD38-ZAP70+, 2 cases CD38+ZAP70-, respectively. Statistics disclosed a correlation between complex karyotype and IgVH without mutation, but no association between karyotype and CD38 or ZAP70 expression.CpG-ODN immunostimulation can obviously raise the detection rate of abnormal karyotypes, especially balanced and unbalance translocations in CLL. FISH is important complement to conventional karyotypic analysis, the combination of both methods can provide more comprehensive genetic information for CLL.No relevant conflicts of interest to declare.

No relevant conflicts of interest to declare.

Abstract 4242

Abstract 4383

We report the establishment of a novel cell line from a patient with acute myelocytic leukemia. The initial growth of this cell line was dependent on the presence of the stromal cell and cytokine interleukine 3. Subsequently, a stroma and cytokine-independent cell line was established, named SH-2. The cell line has proliferated continuously in vitro for more than 24 months. The SH-2 cell line showed identical chromosomal alterations to that of the initial bone marrow aspiration specimen, demonstrated a t(16;17))(q24;q12) translocation accompanied by deletions of y and 17 and triple 19.Chromosome painting FISH and Multi-FISH conformed the karyotype.SH-2 cells expressed myeloid antigens CD13, CD33 and MPO, SH-2 co-expressed NK markers CD16 and CD56. The loss of one p53 allele were proven by chromosome painting, FISH. A point mutation of CAG to CAT at codon 576 of extron 5 in another p53 allele was found by direct sequencing of DNA. Neither Epstein-Barr virus nor mycoplasma was not detected in SH-2 cells. DNA fingerprinting confirmed the authenticity of the cell line. Cytokines of GM-CSF,IL-3,IL-6,SCF,IL-4 and IL-5 can improve the proliferation of SH-2. SH-2 has colony formality and tumorigenic capacity in nude mice. The breakpoints of chromosomes 16 and 17 were localized RP11-356C4(16q24.3)and between BAC clone RP1-161P9 and RP11-47L3 corresponding to 17q12. The establishment of an myelocytic leukemia cell line with t(16;17)(q24;q12) could be valuable for the study of leukemogenesis and for the research of cloning the new gene involved in the t(16;17)(q24;q12) translocation.

Translocations involving 21q22 are commonly observed in both de novo and therapy-related acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). They often result in the disruption of RUNX1 and give rise to fusion genes consisting RUNX1 and different partner genes which contribute to leukemogenesis. At present, at least 21 such translocations have been reported in the literature. We report here two novel translocations involving the RUNX1 gene: t(1;21)(q12;q22) in a 53-year-old female with AML-M5b and t(11;21)(q13;q22) in a 65-year-old male with AML-M2. The abnormalities revealed by R-banding karyotypic analysis were confirmed by interphase and metaphase fluorescence in situ hybridization (FISH), chromosome painting (CP), and M-FISH.

As a newly identified cytogenetic abnormality, idic(20q−) has been reported in thirteen cases of myelodysplastic syndrome (MDS), one case of chronic myelomonocytic leukemia, and one case of acute myeloid leukemia (AML) since 2004. Here we report additional seven cases consisting of 3 MDS, 2 AML and 2 acute lymphocytic leukemia (ALL). A karyotype analysis using R-banding technique revealed an i(20q−) as a sole anomaly in 5 of them and as a secondary change in other 2 cases: one was a B-cell ALL whose leukemic cells at presentation had a karyotype of 45, XY, dic(9;20)(p11;q11). However, an idic(20q−) was found coexistent with the dic(9;20) as relapse; another was a Ph positive ALL whose leukemic cells simultaneously contained t(9;22)(q34;q11) and idic(20q−). A series of FISH using multiple probes such as the centromeric probes specific for chromosomes 9 and 20, the subtelomeric probe for 20q, the locus-specific probe for 20q12, the whole chromosome paint probes for chromosomes 9 and 22 and the translocation probe for t(9;22) demonstrated the idic(20q−) to be actually a der(20)idic(20)(p11)del(20)(q11q13), confirmed the dic(9;20)(p11;q11) in case 6 and revealed a BCR/ABL fusion gene in case 7. Among them, 2 MDS patients survived and anemic except one lost to follow-up, 2 AML and 2 ALL patients did not obtain complete remission and died with short survivals. Our study brings the total number of cases with idic(20q−) to 22 and suggests that the disease spectrum of idic(20q−) is not restricted to myeloid disorders, and it also includes ALL.

Translocations involving 21q22 are commonly observed in both de novo and therapy-related acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). They often result in the disruption of RUNX1and give rise to fusion genes consisting RUNX1and different partner genes which contribute to leukemogenesis. At present, at least 21 such translocations have been reported in the literature. We report here two novel translocations involving the RUNX1gene: t(1;21)(q12;q22) in a 53-year-old female with AML-M5b and t(11;21)(q13;q22) in a 65-year-old male with AML-M2. The abnormalities revealed by R-banding karyotypic analysis were confirmed by interphase and metaphase fluorescence in situ hybridization (FISH), chromosome painting (CP), and M-FISH.

We report the establishment of a novel cell line from a patient with acute myelocytic leukemia. The initial growth of this cell line was dependent on the presence of the stromal cell and cytokine interleukine 3. Subsequently, a stroma and cytokine-independent cell line was established, named SH-2. The cell line has proliferated continuously in vitro for more than 24 months. The SH-2 cell line showed identical chromosomal alterations to that of the initial bone marrow aspiration specimen, demonstrated a t(16;17))(q24;q12) translocation accompanied by deletions of y and 17 and triple 19.Chromosome painting FISH and Multi-FISH conformed the karyotype.SH-2 cells expressed myeloid antigens CD13, CD33 and MPO, SH-2 co-expressed NK markers CD16 and CD56. The loss of one p53 allele were proven by chromosome painting, FISH. A point mutation of CAG to CAT at codon 576 of extron 5 in another p53 allele was found by direct sequencing of DNA. Neither Epstein-Barr virus nor mycoplasma was not detected in SH-2 cells. DNA fingerprinting confirmed the authenticity of the cell line. Cytokines of GM-CSF,IL-3,IL-6,SCF,IL-4 and IL-5 can improve the proliferation of SH-2. SH-2 has colony formality and tumorigenic capacity in nude mice. The breakpoints of chromosomes 16 and 17 were localized RP11-356C4(16q24.3)and between BAC clone RP1-161P9 and RP11-47L3 corresponding to 17q12. The establishment of an myelocytic leukemia cell line with t(16;17)(q24;q12) could be valuable for the study of leukemogenesis and for the research of cloning the new gene involved in the t(16;17)(q24;q12) translocation.

As a newly identified cytogenetic abnormality, idic(20q−) has been reported in thirteen cases of myelodysplastic syndrome (MDS), one case of chronic myelomonocytic leukemia, and one case of acute myeloid leukemia (AML) since 2004. Here we report additional seven cases consisting of 3 MDS, 2 AML and 2 acute lymphocytic leukemia (ALL). A karyotype analysis using R-banding technique revealed an i(20q−) as a sole anomaly in 5 of them and as a secondary change in other 2 cases: one was a B-cell ALL whose leukemic cells at presentation had a karyotype of 45, XY, dic(9;20)(p11;q11). However, an idic(20q−) was found coexistent with the dic(9;20) as relapse; another was a Ph positive ALL whose leukemic cells simultaneously contained t(9;22)(q34;q11) and idic(20q−). A series of FISH using multiple probes such as the centromeric probes specific for chromosomes 9 and 20, the subtelomeric probe for 20q, the locus-specific probe for 20q12, the whole chromosome paint probes for chromosomes 9 and 22 and the translocation probe for t(9;22) demonstrated the idic(20q−) to be actually a der(20)idic(20)(p11)del(20)(q11q13), confirmed the dic(9;20)(p11;q11) in case 6 and revealed a BCR/ABLfusion gene in case 7. Among them, 2 MDS patients survived and anemic except one lost to follow-up, 2 AML and 2 ALL patients did not obtain complete remission and died with short survivals. Our study brings the total number of cases with idic(20q−) to 22 and suggests that the disease spectrum of idic(20q−) is not restricted to myeloid disorders, and it also includes ALL.

Objective To explore the inducing differentiation and apoptosis in a novel human acute monocytic leukemic cell line SHI-1. Methods Cell morphological analysis, NBT reduction test, the expression of CD11b and CD14, cell cycle analysis and binding of annexinV tested by FCM, DNA electrophoresis were performed to evaluate whether tributyrin (TB), arsenic trioxide (As2O3), and 12-O-tetradecanoyl-phorbol-13 acetate (TPA) could induce the differentiation and apoptosis in the SHI-1 cell line. Results The results of morphological analysis, NBT reduction test, and FCM assay showed that TB could induce differentiation of SHI-1 cells. The SHI-1 cell line presented typical apoptotic evidences including morphology features, DNA ladders and the increased apoptotic rate determined by FCM. Moreover, the SHI-1 cell line presented typical apoptotic morphology after being treated with As2O3. The apoptotic rate of the SHI-1 cell line treated with As2O3 was increased determined by FCM. The expression level of CD14 was upregulated while that of CD11b was unchanged in the SHI-1 cell line. Most of the SHI-1 cells adhered to the flask after being treated with TPA for 24 hours. Conclusions TB may produce dual effects of differentiation and apoptosis. The cell line could be induced to differentiation partially or apoptosis after being treated with 0.5μM, 1.0μM, and 2.0μM As2O3. TPA could induce differentiation and adhesion of the SHI-1 cell line.

Objective