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D C Liang

Publications and source records attributed to D C Liang.

At least 19 recordsLinked to original sources
PubMed1996

Clinicopathologic, cytogenetic, and molecular studies of 13 Chinese Patients with Ki-1 anaplastic large cell lymphoma. Special emphasis on the tumor response to 13-cis retinoic acid.

BACKGROUND: The clinicopathologic and molecular features of the newly characterized Ki-1 lymphoma, although well studied in Western countries, are less well described in Asia. METHODS: Pathology material of lymphoma cases, consecutively diagnosed at our institution between 1986 and 1994, was reviewed. The cases fulfilling the diagnostic criteria of Ki-1 lymphoma were selected, and their clinicopathologic features were studied. Immunohistochemistry and cytogenetic studies of the lymphoma tissues, and molecular analysis for nucleophosmin (NPM) gene translocation were performed. RESULTS: A total of 13 cases (2.3%) of Ki-1 large cell lymphoma were identified from a total of 572 cases of non-Hodgkin's lymphoma diagnosed during this period of time. There were 10 men and 3 women with a median age of 43 years (range, 18 to 61 years). The initial presenting sites included the skin alone in five cases, lymph node alone in one case, both skin and lymph node in five cases, and the stomach in one case. All cases had large cell morphology, with the majority of the neoplastic cells expressing Ki-1 antigen (CD30). Except for the case with gastric involvement, all other cases were T-cell lymphomas. One of seven cases examined had chromosomal abnormality of t (2;5). Rearrangement of the NPM gene at chromosome 5 was detected by Southern blot analysis in three of nine cases. Two of seven cases tested by reverse-transcriptase polymerase chain reaction showed fusion of the NPM gene and anaplastic lymphoma kinase gene. Seven (78%) of 9 patients who had received systemic chemotherapy with a standard cyclophosphamide, doxorubicin, vincristine, and prednisolone regimen obtained a complete remission (CR). The median duration of remission was 33 months. Three (60%) of 5 patients, of whom 4 recurred from previous intensive chemotherapy, achieved a prolonged CR with treatment with 13-cis retinoic acid (RA). The median survival of the whole group has not yet been reached at a median follow-up of 40 months. CONCLUSIONS: The clinicopathologic and molecular features of Ki-1 lymphoma of Chinese patients are comparable to those reported from Western countries. 13-cis RA appears to be an effective treatment of Ki-1 lymphoma.

Adult↗
PubMed1996

Crystal structure of R-phycoerythrin from Polysiphonia urceolata at 2.8 A resolution.

The structure of R-phycoerythrin (R-PE) from Polysiphonia urceolata was determined at 2.8 A resolution. The crystals belong to space group R3 with unit cell dimensions of a = b = 189.8 A, c = 60.1 A. The subunit composition of R-PE is (alpha 2 beta 2)3 gamma. The three-dimensional structure of R-PE was solved by the multiple isomorphous replacement method. After several cycles of model building and refinement, the crystallographic R-factor of the final model is 18.0% with data from 10.0 to 2.8 A resolution. The four phycoerythrobilin chromophores alpha 84, alpha 140a, beta 84 and beta 155 in an (alpha beta) unit are each covalently bound to a cysteine residue through ring A. The phycourobilin chromophore is bound to cysteine beta 50 by ring A and bound to cysteine beta 61 by ring D. The ring A and ring D of phycourobilin deviate from the conjugate plane formed by ring B and ring C and the four rings form a boat-shaped structure. R-PE contains a 34 kDa gamma subunit that is assumed to lie in the central channel of the molecular disc (alpha 2 beta 2)3. The energy transfer and relationship between cysteine residues and chromophores are discussed.

Bacterial Proteins↗
PubMed1996

Pancreatitis in children--experience with 43 cases.

UNLABELLED: Pancreatitis in children is not common and can be associated with severe morbidity and mortality. We encountered 43 children, ranging in age from 2 to 18 years, with pancreatitis over the past 10 years. The diagnosis of pancreatitis was made in those patients who showed: (1) significant intra-operative pathology or; (2) clinical findings of pancreatic inflammation and laboratory confirmation. More than one third (16 cases) of the cases were due to trauma, other causes included systemic disease (10), structural disease (8), and toxins or drugs (4). Five cases were classified as idiopathic. Most of the patients presented with abdominal pain (95%) and vomiting (56%). Jaundice was found in 7 patients and an abdominal mass in 2. Morbidity included pseudocyst (10), relapse (4), hyperglycaemia (4) and miscellaneous problems. Eight (50%) of the patients with trauma and 6 (86%) of the patients with structural diseases required surgery. Other patients were managed conservatively with bowel rest, gastric decompression, intravenous fluid and total parenteral nutrition. One case had a fatal outcome. All the survivors did well in long term follow up. Relevant literature has been reviewed and the sensitivity of various diagnostic modalities compared and discussed. A lesser known association between pancreatitis and structural anomalies such as choledochal cyst is discussed. To our knowledge, the present review is the first on pancreatitis in Chinese children. CONCLUSION: Pancreatitis can occur from a wide variety of causes and may result in severe complications. Early diagnosis, close monitoring and aggressive intervention are mandatory to reduce morbidity and mortality.

Abdomen, Acute↗
PubMed1996

Purification and crystal growth of F1-ATPase from pig heart mitochondria.

A method has been evolved toward the aim of getting suitable crystals for high resolution of structural analysis of F1-ATPase by X-ray crystallography. The different conditions for crystal growth of ATPase that were isolated and purified by different methods from pig heart mitochondrial ATP synthase had been compared and screened. A simple method for purification of F1-ATPase was adopted. The F1-ATPase is released with chloroform from submitochondrial particles. Then it was treated with fractional precipitation of (NH4)2SO4 and finally was further purified by employing the sephadex G 200 column. The crystals of F1-ATPase were usually obtained after a few months. They appeared to have uniform morphology of tetrahedron. They diffracted to a resolution of 7A. The diffraction data were collected on the XRD-100 Siemens Area Detector. According to a total of 240 frames, the cell parameters obtained are a = b = 147 A, c = 208 A, alpha = beta = gamma = 90 alpha, the probable space group is P4 or its antipode. The reproducibility of this method for crystallization of F1-ATPase is good.

Animals↗
PubMed1996

High incidence of TEL/AML1 fusion resulting from a cryptic t(12;21) in childhood B-lineage acute lymphoblastic leukemia in Taiwan.

Despite its rarity by routine karyotypic analysis, cryptic t(12;21)(p12-13;q22) translocation leading to TEL/AML1 fusion has been recognized as the most frequent genetic rearrangement in childhood acute lymphoblastic leukemia (ALL) in two recent studies, one from France and the other from the United States. To estimate the frequency of this abnormality in the Chinese population, we studied 41 children with ALL and 17 with acute myeloid leukemia (AML) in two medical centers in Taiwan, using the reverse transcriptase polymerase chain reaction (RT-PCR) assay. Results of this analysis demonstrated a 17% frequency of this translocation in the ALL population overall and 19% in patients with B-lineage ALL, similar to previous findings in Caucasian children. None of the patients with AML had TEL/AML1 fusion transcripts. In addition to its association with the B-lineage immunophenotype, TEL/AML1 was also correlated with a low presenting leukocyte count and favorable age (1-10 years). These findings, combined with earlier reports, indicate that TEL/AML1 fusion is the most frequent genetic abnormality in childhood ALL, regardless of race. Molecular diagnosis of t(12;21)-positive ALL may identify a subgroup of patients who do not require intensive treatment for cure.

Adolescent↗
PubMed1996

Lack of TEL-AML1 fusion transcript resulting from a cryptic t(12;21) in adult B lineage acute lymphoblastic leukemia in Taiwan.

Cryptic t(12;21)(p12-13;q22) leading to TEL-AML1 fusion has recently been recognized as the most frequent genetic rearrangement in childhood acute lymphoblastic leukemia (ALL) in Western countries. More recently, we found a similar frequency of this abnormality in Chinese children with ALL in Taiwan. In this study, we assessed further the frequency of TEL-AML1 fusion as well as that of BCR-ABL in Chinese adults with ALL, using reverse transcriptase-polymerase chain reaction assays. Among the 81 cases with newly diagnosed B lineage ALL studied, none had the TEL-AML1 fusion whereas 30 had the BCR-ABL fusion. The lack of cases with the TEL-AML1 fusion together with the high frequency of BCR-ABL fusion could largely account for the poorer outcome of adult ALL as compared with childhood ALL.

Adolescent↗
PubMed1995

Role of granulocyte colony-stimulating factor as adjunct therapy for septicemia in children with acute leukemia.

The granulocyte colony-stimulating factor (G-CSF) has been shown to accelerate recovery from severe neutropenia and to decrease the incidence of documented infections after intensive chemotherapy in cancer patients. However, the routine prophylactic use of G-CSF is expensive. This study was conducted to determine the role of G-CSF as adjunct therapy for septicemia following neutropenia caused by chemotherapy in children with acute leukemia. Fifty consecutive episodes of septicemia were studied involving 34 episodes of Gram-negative, 7 episodes of Gram-positive, 5 episodes of polymicrobial bacterial septicemia, one episode of fungemia, and 3 episodes of disseminated fungal infection. In the first 25 episodes, G-CSF was not used (group A). For the next 16 episodes, G-CSF 200 micrograms per square meter per day subcutaneously was given immediately after the septicemia was documented until the absolute neutrophil count was maintained at more than 1,500 per cubic millimeter (group B). Thereafter, G-CSF at the same dose as that of group B was prophylactically used in all the children who received high-dose cytosine arabinoside-containing regimens. Nine episodes of septicemia occurred (group C). The incidences of mortality per episode of septicemia in groups A, B, and C were 12.0% (3/25), 12.5% (2/16) and 0% (0/9), respectively. Statistically, there was no difference between the three groups overall and in pair-wise comparisons (all P > 0.5). The durations of G-CSF administration in group B ranged from 6 to 26 days with a median of 12 days and the durations of G-CSF administration in group C ranged from 10 to 23 days with a median of 19 days. With or without G-CSF, there may be no significant difference in the mortality of septicemia following neutropenia caused by chemotherapy in children with acute leukemia.

Acinetobacter Infections↗
PubMed1995

Treatment of platelet alloimmunization with intravenous immunoglobulin in a child with aplastic anemia.

A 9-year-old girl with severe refractory aplastic anemia had become refractory to platelet transfusion due to platelet alloimmunization. As a result, a huge right parieto-temporo-occipital cerebral hematoma and a subarachnoid hemorrhage subsequently occurred. Intravenous immunoglobulin (IVIG) (Green Cross, Taiwan) at a dose of 0.4 g/kg/day for 5 days, followed by another 3 doses during the following 5 days, and combined with large-dose platelet transfusions effectively controlled the bleeding by elevating the platelet count to above 100 x 10(3)/mm3. The patient soon recovered with only a mild sequela. Two months later, because of multiple caries and a periodontal abscess, dental extraction needed to be performed. IVIG (0.4 g/kg/day x 6 days) enabled surgery to proceed by elevating the platelet count to above 55 x 10(3)/mm3, and no bleeding complications occurred during or after the procedure. The potential benefit of high-dose IVIG in modulating platelet alloimmunization is a result of increasing the survival of transfused platelets. Thus, this therapy is recommended when patients with platelet alloimmunization have critical bleeding episodes or undergo surgical procedures.

Anemia, Aplastic↗
PubMed1995

Neonatal alloimmune thrombocytopenia in Taiwan due to an antibody against a labile component of HPA-3a (Baka).

We report on two siblings who developed severe neonatal alloimmune thrombocytopenia (NAIT) due to an alloantibody against a labile component or components of the HPA-3a (Baka) antigen. The antibody reacted only with fresh, unfixed platelets by the solid-phase red cell adherence test, immunofluorescence test and mixed passive haemagglutination test. In the latter method, weakly fixed platelets also gave a weak positive reaction. Monoclonal-antibody-specific immobilization of platelet antigens and immunoblotting tests gave negative results. Our findings may possibly help to explain why in some cases of NAIT no platelet-specific antibody is demonstrable in tests with fixed or solubilized platelets.

Antibodies, Monoclonal↗
PubMed1995

The Le(a) antigen and neonatal hyperbilirubinemia in Taiwan.

Neonatal jaundice is known to be more severe in Taiwanese infants than in Caucasian infants. Although ABO fetomaternal incompatibility and glucose-6-phosphate dehydrogenase deficiency have been shown to play a role in the etiology of neonatal jaundice in some Taiwanese infants, the etiology in the majority of cases is unknown. In this study we found that in Taiwanese newborn infants, the red cell Le(a) antigen appeared later in infants who were jaundiced (peak serum bilirubin levels of > 12 mg/dl during the first week of life) than in infants who were not. However, the Leb antigen, and hence the transferase encoded by the Se and Se(w) genes, did not appear to be similarly involved in the etiology of physiological jaundice. Thus it would appear that the Le gene-specified transferase is less active or has a delayed function, in jaundiced infants. The relationship between the Le gene-specified transferase and bilirubin has yet to be established.

Asian People↗
PubMed1994

A proposed interaction model of the insulin molecule with its receptor.

Based on the extensive structural comparisons among the determined structures of the different species and crystal forms of insulin and its derivatives in our laboratory, it was suggested that the binding interaction with the receptor molecule should take place mainly on an amphipathic surface of the insulin molecule. In the middle of this amphipathis surface, there was a hydrophobic surface with an area of about 150 A2, while the polar and charged groups distributing around the hydrophobic surface constructed a hydrophilic zone. The hydrophobic surface was usually covered by the extended B-chain C-terminal peptides with great mobility. The angle between the proposed binding interaction surface and the surface of dimerization was about 20 degrees. The results from studies on structures of A1-(L-Trp) insulin and A1-(D-Trp) insulin confirmed the interaction mechanism model we proposed.

Amino Acid Sequence↗
PubMed1994

A clinicopathological study of Langerhans cell histiocytosis.

BACKGROUND: Langerhans cell histiocytosis encompasses a wide clinical spectrum, from a benign localized disease to acute generalized disease with fatal outcome. Here the histological features and clinical data for thirteen patients are reviewed and compared. The antigenic phenotype of the proliferating cells in Langerhans cell histiocytosis was also studied. METHODS: The antibodies used included S-100 protein, vimentin, peanut agglutinin, HLA-DR, leukocyte common antigen, UCHL-1, CD 20, lysozyme, alpha 1-antitrypsin and epithelial membrane antigen. RESULTS: Six patients had localized lesions affecting a bone or its surrounding soft tissue. Four patients had multifocal disease without organ dysfunction. All patients of these two categories survived, except for one adult who died of hypertensive cerebral hemorrhage. Three patients had multifocal disease with liver, lung or bone marrow dysfunction. One died and two were lost to follow up. CONCLUSIONS: There was no significant difference in pathological findings between localized disease and multifocal disease. Immunohistochemical examinations using a panel of antibodies, including S-100 protein, peanut agglutinin, HLA-DR and vimentin, were very helpful for diagnosis of Langerhans cell histiocytosis.

Adult↗
PubMed1993

Cranial computed tomography in children with acute lymphoblastic leukemia after prophylactic treatment with cranial radiation therapy and intrathecal methotrexate.

BACKGROUND AND METHODS: Thirty-one children with acute lymphoblastic leukemia (ALL) who had received cranial radiation therapy (CrRT) and five concomitant doses of intrathecal methotrexate (IT MTX) for central nervous system prophylaxis (CNSP) and who had an event-free survival exceeding 5 years had cranial computed tomography (Cr CT) examination. The fractional dose for 21 of them was 1.5 Gy. The interval between the completion of CNSP and the time of Cr CT ranged from 5 to 8.5 years, with a median of 5 years 2 months. RESULTS: Unlike the previous reports in the literature that 9-77% of children with ALL who had received Cr RT 18 Gy and IT MTX as CNSP had CT scan abnormalities, in this study no patient had CT scan abnormalities. CONCLUSIONS: Our results might be attributable to the fractional dose of Cr RT being adequate, the IT chemotherapy being suitable, and the systemic chemotherapy not being intensive.

Brain↗
PubMed1993

Computed tomography of spontaneous intracranial haemorrhage due to haemostatic disorders in children.

Intracranial haemorrhage is a serious problem in haemostatic disorders in children. Intracranial bleeding is sometimes more marked than suspected clinically. Computed tomography (CT) permits accurate, sensitive diagnosis of intracranial haemorrhage. We report 13 patients; 3 patients with hypoprothrombinaemia, 4 patients with thrombocytopenia or platelet dysfunction and 6 with haemophilia A, B or Von-Willebrand's disease. One patient with hypoprothrombinaemia had a subarachnoid hemorrhage (SAH), one a subdural haematoma (SDH) and the third a combination of SAH, SDH and intracerebral haematoma (ICH). One patient with thrombocytopenia or platelet dysfunction had a SDH, while the others had ICH. In the six patients with haemophilia A, B or Von-Willebrand's disease, there were four examples of ICH, five of SAH and six of SDH. A neurosurgical procedure was performed in only one patient. Three children died of serious intracranial complications with uncal herniation.

Adolescent↗
PubMed1993

Health status of patients with childhood acute lymphoblastic leukemia in continuous complete remission for over five years. The Taiwan Children's Cancer Study Group.

Ninety-seven patients with childhood acute lymphoblastic leukemia (ALL) have achieved complete continuous first remission for more than five years. They were treated by Taiwan Children's Cancer Study Group protocol 821 or protocol 842. Their present health status was evaluated using blood counts, immunology, a psychiatric analysis and growth parameters. Hemoglobin and platelet counts rose quickly to the normal range after complete remission was achieved, then remained at low normal throughout the course. The leukocyte counts responded immediately to chemotherapy, usually recovering to about 5,000/uL, then gradually increasing after completion of chemotherapy. The absolute neutrophil counts were at a low normal level during chemotherapy, then gradually recovered to the normal level after chemotherapy was completed. Immunologic investigation after completion of chemotherapy showed that the subsets of lymphocytes were nearly all in the normal range for the 38 patients tested. On the other hand, in 17 patients tested for T-cell function, it was found that 29.4% had low natural killer (NK) cell cytotoxicity, 11.8% had an abnormal phytohemagglutinin (PHA) test and all had abnormally low IL-2 production (in vitro). There were 29 patients who had psychiatric analyses; the full IQ was borderline in 10.3%. The primary or middle school academic scores of 55 patients were reported; 15% of them belonged to the lower one-third of the class. Height was assessed by the standard deviation score from the mean for 58 patients. The differences were statistically insignificant; however, there were six patients whose growth curves crossed over their initial percentile line.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗