Centenarian clocks: epigenetic clocks for validating claims of exceptional longevity

Claims surrounding exceptional longevity are sometimes disputed or dismissed for lack of credible evidence. Here, we present three DNA methylation-based age estimators (epigenetic clocks) for verifying age claims of centenarians. The three centenarian clocks were developed based on n = 7039 blood and saliva samples from individuals older than 40, including n = 184 samples from centenarians, 122 samples from semi-supercentenarians (aged 105 +), and 25 samples from supercentenarians (aged 110 +). The oldest individual was 115 years old. Our most accurate centenarian clock resulted from applying a neural network model to a training set composed of individuals older than 40. An epigenome-wide association study of age in different age groups revealed that age effects in young individuals (age < 40) are correlated (r = 0.55) with age effects in old individuals (age > 90). We present a chromatin state analysis of age effects in centenarians. The centenarian clocks are expected to be useful for validating claims surrounding exceptional old age.

Long-term outcome of allogeneic human leukocyte antigen-matched sibling-donor peripheral blood stem cell transplantation in leukaemia patients

Between 1993 and July 2008, a total of 354 leukaemic patients received either allogeneic bone marrow transplantation (BMT) [n = 180] or peripheral blood stem cell transplantation (PBSCT) [n = 174] from human leukocyte antigen-matched sibling donors. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin A and methotrexate. When comparing with BMT group, patients in the PBSCT group received much higher nucleated cells and CD34+ cells, and had much faster recovery of the neutrophil and platelet counts. The probability of developing acute GVHD was slightly higher in PBSCT patients (P = 0.02). The probability of chronic GVHD (cGVHD) in PBSCT was much higher in PBSCT (70 +/- 5.4%, extensive 48 +/- 6.5%) than in BMT (25 +/- 4.7%, extensive 10 +/- 3.4%; P < 0.001). Chronic GVHD was associated with long-term impairment of life quality and decreased quality-adjusted survival. In standard-risk leukaemia, use of PBSCT was associated with higher cGVHD, transplant-related mortality and a trend for decreased overall survival. The results suggest that allogeneic PBSCT is associated with high incidence of cGVHD in Chinese patients and its long-term risk and benefit remains to be defined in early stage of leukaemia.

Improved treatment results for childhood acute myeloid leukemia in Taiwan

To improve treatment results for children with de novo acute myeloid leukemia (AML), we introduced a novel protocol, Taiwan Pediatric Oncology Group-AML-97A, for AML other than acute promyelocytic leukemia (APL), for which modified conventional protocols were used. From January 1, 1997, to December 31, 2002, 141 children younger than 17 years old with de novo AML were enrolled. In total, 117 patients with non-APL AML were treated with induction therapy of idarubicin and cytarabine (Ara-C), postremission therapy with high-dose Ara-C - containing regimens for four monthly courses, and moderate-dose therapy with idarubicin and Ara-C for four monthly courses. The first 19 patients with APL were treated with all-trans retinoic acid, idarubicin and Ara-C, with the remaining five patients receiving all-trans retinoic acid and idarubicin, followed by maintenance therapy for 2 years. Stem cell transplantation was performed in 29 patients in first remission with a similar outcome as chemotherapy alone. The remission rate in the AML-97A study was 90%, the 5-year survival 51 +/- 5.3% (s.e.) and the 5-year event-free survival 50 +/- 4.8%; for APL, these were 100%, 86 +/- 7.0, and 75 +/- 9.8%. For the whole group, the 5-year survival was 57 +/- 4.7% and the 5-year event-free survival 54 +/- 4.4%. The AML-97A regimen was well tolerated.

Diagnostic and prognostic value of [(18)F]fluorodeoxyglucose positron emission tomography for recurrent head and neck squamous cell carcinoma

PURPOSE

Patients with recurrent head and neck squamous cell carcinoma (HNSCC) present a diagnostic and therapeutic challenge. We evaluated the diagnostic accuracy and prognostic value of [(18)F]fluorodeoxyglucose positron emission tomography (PET) in this patient population.

PATIENTS AND METHODS

We performed a retrospective review of 143 patients with previously treated HNSCC who underwent 181 PET scans at our institution from May 1996 through April 2001 to detect recurrent disease. Disease recurrence within 6 months was used as the gold standard for assessing true disease status at PET.

RESULTS

With equivocal sites considered positive, the sensitivity and specificity of PET for detecting recurrence overall were 96% and 72%, respectively. PET was highly sensitive and specific at regional and distant sites. At local sites, sensitivity was high, but specificity was lower because of false-positive findings. One fifth of all false-positive PET scans occurred at sites of known inflammation or infection. The area under the curve for a receiver operator characteristic curve on the basis of standardized uptake value (SUV) was 0.882 +/- 0.025. PET interpretation, SUV, and physical examination were independent predictors of relapse-free and overall survival in a time-dependent, multivariate proportional hazards model. An increase in SUV by one unit increased the relative risk (RR) of relapse by 11% and the RR of death by 14%. A positive PET interpretation increased the RR of relapse by four-fold and the RR of death by seven-fold.

CONCLUSION

PET was a highly sensitive method of detecting recurrent HNSCC and provided important prognostic information for relapse-free and overall survival.

The mRNA expression of placental glutathione S-transferase isoenzyme in hamster buccal-pouch carcinomas using reverse transcription-polymerase chain reaction

Placental glutathione S-transferase (GST-P) may facilitate cell proliferation and inhibit apoptosis, hence allowing for the expansion of a population of initiated tumor cells. The enhanced expression of GST-P at the protein level has been reported previously in chemically induced oral carcinomas in hamster buccal-pouch mucosa but the expression of GST-P at the mRNA level has not yet been demonstrated. The purpose of the present study was to assess the GST-P mRNA expression in 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal-pouch carcinomas using a reverse transcription-polymerase chain reaction (RT-PCR). Thirty-five outbred, young (6 weeks old), male, Syrian golden hamsters (Mesocricatus auratus) were randomly divided into one experimental group (15 animals), and two control groups (10 animals each). Bilateral pouches of a group of 15 animals of the experimental group were painted with a 0.5% DMBA solution three times a week for 12 weeks while each animal of one of the control groups was similarly treated with mineral oil. Another control group of 10 animals was untreated throughout the experiment. Areas of dysplasia and squamous-cell carcinomas with a 100% tumor incidence developed in all of the DMBA-treated buccal pouches. The mineral oil-treated and untreated pouches revealed no obvious changes. Placental glutathione S-transferase mRNA was demonstrated to be present amongst all the 12-week DMBA-treated hamster buccal-pouch mucosa animals, but not for the untreated animals or the animals for which the buccal pouch was treated with mineral oil. Multiple potential regulatory pathways including gene amplification, enhanced mRNA stability, chromosomal translocation/gene rearrangement, and hypomethylation of the promoter region can contribute to the overexpression of GST-P mRNA in DMBA-induced hamster buccal-pouch carcinomas. Further study is necessary to completely understand which candidate mechanism(s) will contribute principally to the increased GST-P mRNA expression in oral experimental carcinogenesis.

Inhibition of cyclooxygenase-2: an approach to preventing cancer of the upper aerodigestive tract

Multiple lines of evidence suggest that cyclooxygenase-2 (COX-2), an inducible form of COX, represents a potential pharmacologic target to prevent cancer. Key data suggesting a causal relationship between increased COX-2 activity and carcinogenesis and possible mechanisms of action of COX-2 in this context will be discussed. The possibility that COX-2 represents a pharmacological target for preventing upper aerodigestive cancers (head and neck, lung) will be emphasized. Importantly, clinical trials have been initiated to assess the chemopreventive properties of selective COX-2 inhibitors.

Philadelphia chromosome-positive acute lymphoblastic leukemia in Taiwan

From January 1986 to December 1998, 26 (23%) of 114 acute lymphoblastic leukemia (ALL) patients older than 15 years were found to have Philadelphia (Ph) chromosome. They accounted for 28% (26 of 94) of the patients with B-lineage ALL. Compared with the other 88 ALL patients, the leukemic cells from all but one Ph-positive ALL patients were early pre-B cells with a higher rate of CD34 expression (92% vs 50%, P<0.05). At presentation, the Ph-positive adult ALL patients had higher circulating blasts (mean 21.4 vs 3.66x10(4)/microl, P<0.05) and lower initial platelet counts (mean 4.47 vs 7.34x10(4)/microl, P<0.01) and showed a trend toward higher frequency of initial central nerve system (CNS) involvement (25% vs 11%, P=0.098) than the others. Among patients with adequate chemotherapy, 16 (64%) of the 25 Ph-positive ALL patients achieved complete remission (CR), an incidence marginally lower than that of Ph-negative ALL (62 of 76, 82%, P=0.06) and significantly lower than that of Ph-negative B-lineage ALL (50 of 58, 86%, P=0.0037). However, all patients relapsed except for those who received allogeneic hemopoietic stem cell transplantation (allo-HSCT). The probabilities of 5-year continuous CR and 5-year survival for Ph-positive adult ALL patients were significantly inferior to those for Ph-negative adult ALL patients (0% vs 12%, P=0.0001, and 7% vs 19%, P=0.047, respectively), and those for Ph-negative B-lineage ALL (0% vs 14%, P<0.0001, and 7% vs 23%, P=0.002, respectively). Prognostic factors were analyzed among the Ph-positive ALL patients including the 26 adults mentioned above and an additional 11 children. No clinical or biological characteristics such as age, sex, initial circulating blast count, extramedullary involvement, or CD34 expression had an impact on the disease outcome. Allo-HSCT in first CR may improve the probability of 5-year continuous CR (100% vs. 0% for those without allo-HSCT, P=0.0091) although only three patients received it in this study. In conclusion, Ph-positive ALL patients tended to have a poor prognosis, regardless of whether other possible risk factors were present or not. Aggressive treatment, such as high-dose chemotherapy with allo-HSCT, should be considered for these patients to improve survival.

The H89 cAMP-dependent protein kinase inhibitor blocks Plasmodium falciparum development in infected erythrocytes

In Plasmodium falciparum, the causative agent of human malaria, the catalytic subunit gene of cAMP-dependent protein kinase (Pfpka-c) exists as a single copy. Interestingly, its expression appears developmentally regulated, being at higher levels in the pathogenic asexual stages than in the sexual forms of parasite that are responsible for transmission to the mosquito vector. Within asexual parasites, PfPKA activity can be readily detected in schizonts. Similar to endogenous PKA activity of noninfected red blood cells, the parasite enzyme can be stimulated by cAMP and inhibited by protein kinase inhibitor.Importantly, ex vivo treatment of infected erythrocytes with the classical PKA-C inhibitor H89 leads to a block in parasite growth. This suggests that the PKA activities of infected red blood cells are essential for parasite multiplication. Finally, structural considerations suggest that drugs targeting the parasite, rather than the erythrocyte enzyme, might be developed that could help in the fight against malaria.

Studies on the effect of surface properties on the biocompatibility of polyurethane membranes

To study the effect of surface properties on the biocompatibility of biomaterials based on the same material, polyurethane membranes with different surface properties were prepared. Myoblast culture and interleukin-1 (IL-1) generation in an air pouch model and in vitro monocyte culture were used to examine biocompatibility of different polyurethane membranes. Polyurethane membranes were found to exhibit significant differences depending on their surface properties prepared by different fabrication processes. When myoblasts were cultured on polyurethane surfaces, the smooth and hydrophobic membrane (F1), prepared by the solvent evaporation process, showed the greatest inhibition of myoblast adhesion compared with other porous and hydrophilic membranes (F2, F3 and F4), prepared by immersing the polymer solution into a precipitation bath. In contrast, IL-1 generation by monocytes/macrophages on the membrane F1 was more severe than those on the porous and hydrophilic membranes. Based on our results, the interaction of biomaterials with various cells is discussed.

Abnormal glucose tolerance in transfusion-dependent beta-thalassemic patients

OBJECTIVE

To study the prevalence of and risk factors for abnormal glucose tolerance in transfusion-dependent beta-thalassemic patients.

RESEARCH DESIGN AND METHODS

A total of 89 transfusion-dependent beta-thalassemic patients were interviewed. Diabetes was previously diagnosed in 14 of them. In the remaining 75 patients, 68 participated in an oral glucose tolerance test. Potential risk factors were identified using the independent t test, chi2 test, and Fisher's exact test. Logistic regression analysis was used to select the independent risk factors that best predicted abnormal glucose tolerance A two-tailed P value of <0.05 was considered to be statistically significant.

RESULTS

The prevalence of impaired glucose tolerance was 8.5% (7 of 82) and that of diabetes was 19.5% (16 of 82). Presentation with diabetic ketoacidosis was 31.1% (5 of 16). The risk factors for abnormal glucose tolerance found in transfusion-dependent beta-thalassemic patients were serum ferritin concentration and hepatitis C infection.

CONCLUSIONS

The interaction of iron overload and hepatitis C infection worsened the prognosis of thalassemic patients. Aggressive iron-chelation therapy as well as prevention and treatment of hepatitis C infection should be mandatory in managing glucose homeostasis in transfusion-dependent beta-thalassemic patients in Taiwan.

Peroxisome proliferator-activated receptor gamma ligands suppress the transcriptional activation of cyclooxygenase-2. Evidence for involvement of activator protein-1 and CREB-binding protein/p300

We investigated whether peroxisome proliferator-activated receptor gamma (PPARgamma) ligands (ciglitazone, troglitazone, and 15-deoxy-Delta(12,14) prostaglandin J(2)) inhibited cyclooxygenase-2 (COX-2) induction in human epithelial cells. Ligands of PPARgamma inhibited phorbol ester (phorbol 12-myristate 13-acetate, PMA)-mediated induction of COX-2 and prostaglandin E(2) synthesis. Nuclear run-offs revealed increased rates of COX-2 transcription after treatment with PMA, an effect that was inhibited by PPARgamma ligands. PMA-mediated induction of COX-2 promoter activity was inhibited by PPARgamma ligands; this suppressive effect was prevented by overexpressing a dominant negative form of PPARgamma or a PPAR response element decoy oligonucleotide. The stimulatory effects of PMA were mediated by a cyclic AMP response element in the COX-2 promoter. Treatment with PMA increased activator protein-1 (AP-1) activity and the binding of c-Jun, c-Fos, and ATF-2 to the cyclic AMP response element, effects that were blocked by PPARgamma ligands. These findings raised questions about the mechanism underlying the anti-AP-1 effect of PPARgamma ligands. The induction of c-Jun by PMA was blocked by PPARgamma ligands. Overexpression of either c-Jun or CREB-binding protein/p300 partially relieved the suppressive effect of PPARgamma ligands. When CREB-binding protein and c-Jun were overexpressed together, the ability of PPARgamma ligands to suppress PMA-mediated induction of COX-2 promoter activity was essentially abrogated. Bisphenol A diglycidyl ether, a compound that binds to PPARgamma but lacks the ability to activate transcription, also inhibited PMA-mediated induction of AP-1 activity and COX-2. Taken together, these findings are likely to be important for understanding the anti-inflammatory and anti-cancer properties of PPARgamma ligands.

Frequency and characterization of platelet-specific antibodies in patients who received multiple platelet transfusions

BACKGROUND AND PURPOSE

Multiple platelet transfusions may induce alloimmunization. Platelet alloimmunization involves human leukocyte antigen (HLA) antibodies and platelet-specific antibodies, which recognize platelet glycoproteins. No data are available about the frequency and characteristics of platelet-specific antibodies in patients who have received multiple platelet transfusions in Taiwan.

METHODS

From June through December 1998, blood samples from 103 patients who had received multiple platelet transfusions were submitted to our laboratory for examination of platelet antibodies. The samples were first screened for HLA antibodies or platelet-specific antibodies using a solid phase method. Positive sera were further tested using an enzyme-linked immunosorbent assay (ELISA) to identify the specificities of the alloantibodies.

RESULTS

Forty of the 103 patients who had received multiple platelet transfusions were positive for platelet-reactive antibodies. Further study using ELISA showed that 22 patients had both HLA and platelet-specific antibodies, 12 patients had HLA antibodies alone, and five patients produced platelet-specific antibodies in the absence of HLA antibodies. Most platelet-specific antibodies were found among patients who had HLA antibodies: 81% of platelet-specific antibodies were found in HLA-immunized patients. The most frequently involved platelet glycoprotein antigens were Ia/IIa and IIb/IIIa.

CONCLUSIONS

HLA antibodies were the most frequently found platelet-reactive antibodies in Taiwanese patients who had received multiple transfusions, although platelet-specific antibodies were also common. The frequency of platelet-specific antibodies was not as low as previously reported.

T cell lymphoproliferative disorder following bone marrow transplantation for severe aplastic anemia

Post-transplant lymphoproliferative disorder (PTLD) is uncommonly of T cell origin, especially following BMT. We describe a 13-year-old boy with severe aplastic anemia (SAA) and no evidence of Fanconi's anemia who underwent BMT at 11 years of age using CY 10 mg/kg once daily i.v. on days -5, -4, antilymphocyte globulin (ALG) 30 mg/kg once daily i.v. on days -5 approximately -3 and CsA from day -1 as conditioning. The BMT failed and he received a further peripheral blood stem cell transplant (PBSCT) 240 days after BMT. Conditioning was with CY 50 mg/kg once daily i.v. on days -5 approximately -2, and ALG 15 mg/kg once daily i.v. on days -4 approximately -2. GVHD prophylaxis included CsA and MTX. Engraftment was later confirmed by cytogenetic studies. Desquamation and ulcers of the oral mucosa and mouth angle developed in the 13th month post PBSCT. A buccal mucosa biopsy on day +524 revealed only plasmacytosis. Immunosuppressants were discontinued at that point. Generalized lymphadenopathy, prolonged fever (waxing and waning) and facial swelling developed in the 18th month post PBSCT. A neck lymph node biopsy on day +601 showed T cell lymphoma of diffuse large cell type with monoclonal TCR gamma-chain gene rearrangement. A FISH study showed that the malignant T cells were of recipient origin. EBV in situ hybridization was negative. He did not receive further treatment apart from discontinuation of immunosuppressants. He was followed up in our out-patient clinic and showed good performance 1170 days post PBSCT. We speculate that a different mechanism was operating in the pathogenesis of T cell lymphoma in this case. Risk factors include SAA and two transplants, conditioned with CY and ALG, long term use of CsA and treatment with azathioprine.

Treatment results of the TPOG-NHL92 protocols for childhood non-Hodgkin's lymphomas in Taiwan: a report from the Taiwan Pediatric Oncology Group (TPOG)

A nation-wide chemotherapeutic trial for childhood non-Hodgkin's lymphoma (NHL) was conducted by the Taiwan Pediatric Oncology Group (TPOG). Four TPOG-NHL92 protocols based on stage and histology were activated in 1992: TPOG-92LD (treatment duration: 8 months) was used for localized (stages I/II) NHL with any histology, 92LB (2 years), 92SNC (5 months), and 92LC (1 year) for advanced (stages III/IV) lymphoblastic (LB), small non-cleaved cell (SNC), and large cell (LC) lymphoma, respectively. From January 1992 through June 1998, 200 children with newly diagnosed NHL from 13 member hospitals of TPOG were enrolled. There were 140 boys and 60 girls. Their ages at diagnosis ranged from 2.4 months to 18.3 years with a median of 8.2 years. There were 54 (27.3%) patients with LB, 94 (47.5%) with SNC including B-cell acute lymphoblastic leukemia (B-ALL), and 50 (25.2%) with LC. Stages I, II, III, and IV (including B-ALL) of the disease comprised 5%, 10%, 43%, and 42% of cases, respectively. There were 176 patients eligible for evaluation of treatment results. The remission rate of induction was 82.4%, induction failed in 22 (12.5%) patients, and nine patients died during induction. As of August 31, 1999, 26 patients relapsed, six died during remission, one patient developed secondary acute myelomonocytic leukemia, and 105 patients remained in continuous remission with a median remission duration of 49 months. The event-free survival (EFS) at 7 years was 63.5%, 61.5% and 65% for LB, SNC, and LC groups (P = 0.8298). The 7-year EFS for stages I/II, III, and IV of the disease was 73%, 68.9%, and 50.3% (P = 0.0212), respectively. We concluded that following the strategy of stratification of therapy, only disease stages had prognostic significance in this study. More efforts are needed to improve our treatment results.

Human monocyte adhesion and activation on crystalline polymers with different morphology and wettability in vitro

This study evaluated the effects of crystalline polyamide (Nylon-66), poly(ethylene-co-vinyl alcohol) (PEVA), and poly(vinylidene fluoride) (PVDF) polymers with nonporous and porous morphologies on the ability of monocytes to adhere and subsequently activate to produce IL-1beta, IL-6, and tumor necrosis factor alpha. The results indicated monocyte adhesion and activation on a material might differ to a great extent, depending on the surface morphology and wettability. As the polymer wettability increases, the ability of monocytes to adhere increases but the ability to produce cytokines decreases. Similarly, these polymers, when prepared with porous surfaces, enhance monocyte adhesion but suppress monocyte release of cytokines. Therefore, the hydrophobic PVDF with a nonporous surface stimulates the most activity in adherent monocytes but shows the greatest inhibition of monocyte adhesion when compared with all of the other membranes. In contrast, the hydrophilic Nylon-66, which has a porous surface, is a relatively better substrate for this work. Therefore, monocyte behavior on a biomaterial may be influenced by a specific surface property. Based on this result, we propose that monocyte adhesion is regulated by a different mechanism than monocyte activation. Consequently, the generation of cytokines by monocytes is not proportional to the number of cells adherent to the surface.

Characterization of acute myeloid leukemia with MLL rearrangements--no increase in the incidence of coexpression of lymphoid-associated antigens on leukemic blasts

MLL gene rearrangements are associated with coexpression of myeloid- and lymphoid-associated antigens on leukemic blasts and a dismal outcome in acute lymphoblastic leukemia (ALL). Whether the same conditions can apply to acute myeloid leukemia (AML) is not quite clear. Rearrangements of the MLL gene were analyzed on 113 patients with newly diagnosed de novo AML in a single institution. Sixteen (14%) of them showed rearranged bands by Southern blot analysis, including three (50%) of six infants, three (14%) of 21 children between 1 and 15 years and 10 (12%) of 86 adults. MLL rearrangements were not only detected in M5 (four of 12 patients, 33%) and M4 (six of 31, 19%) subtypes but also in other non-M4-M5 AML (six of 70, 9%), including M1, M2 and M7, but not M3 subtype. Seven patients had chromosomal abnormalities involving 11q23, but nine did not. The latter comprised three (6%) of 48 patients with normal karyotype, one with t(8;21), none with t(15;17), inv(16) or t(9;22), and four (15%) of 27 with cytogenetic aberrations other than those specific structural abnormalities. In contrast to ALL, AML patients with MLL rearrangements did not tend to coexpress lymphoid- and myeloid-associated antigens simultaneously on leukemic blasts and have similar outcome as those without the gene rearrangements.

Bone marrow transplantation from an HLA-matched unrelated donor for treatment of Chediak-Higashi syndrome

Chediak-Higashi syndrome (CHS) is a rare autosomal recessive disease characterized by partial albinism and large granules in all granule-containing cells. It is also associated with recurrent pyogenic infections secondary to impaired leukocyte function. Most patients with CHS enter an accelerated phase that leads to repeated infections and bleeding complications, often resulting in death. The first accelerated phase may occur shortly after birth or several years later. There are no curative treatments, and bone marrow transplantation (BMT) is the treatment of choice. Here, we report the case of a boy with CHS. The diagnosis was made at the age of 1 month, on the basis of the characteristic clinical findings and family history. He received BMT from an HLA-matched unrelated donor. After BMT, fluorescent cytometric analysis of polymorphonuclear leukocytes showed normalized cellular granularity and a normal increase in CD11b expression on N-formylmethionyl-leucyl-phenylalanine stimulation. The accelerated phase did not develop during 27 months of follow-up. Without BMT, CHS is usually fatal before the age of 10 years. BMT from an unrelated donor may be an effective treatment option for those who lack sibling donors. In addition to the characteristic leukocytic dysfunctions, fluorescent cytometric analysis of cellular granularity and surface molecules offer useful diagnostic information.

Development of acute lymphoblastic leukemia in a child after treatment of Langerhans cell histiocytosis: report of one case

Langerhans cell histiocytosis (LCH) is a group of poorly understood disorders. To our knowledge, LCH is a non-malignant disorder. The association of LCH with a secondary neoplasm has not been well assessed, however, a few cases have been reported. We report a case of LCH, a localized osteolytic lesion over metaphysis of left femur, who was treated with local curettage and chemotherapy with vincristine, prednisone and 6-mercaptopurine (6-MP) for eight months from end of 1991 to August, 1992. Six years later, she had acute lymphoblastic leukemia (ALL) in 1998. In review of current literature, only 5 cases of LCH, including our case, have preceded ALL. The possible association, a reactive process or a therapy-related process, between LCH and acute leukemia is still unclear at present and needs to be explored by more studies in the future.

Minimally differentiated acute myeloid leukemia in Taiwan: predominantly occurs in children less than 3 years and adults between 51 and 70 years

Acute myeloid leukemia (AML) with minimal differentiation was usually referred to as acute undifferentiated leukemia in the past. With the help of immunophenotyping, this subtype of leukemia was shown to express myeloid antigens on the blasts and was designated AML-M0 by FAB Cooperative Study Group in 1991. Among the 423 consecutive newly diagnosed de novo AML at our institution, 12 (2.8%) were of M0 subtype. The proportion of M0 in AML was higher in children than in adults (8.2% vs 1.7%). Four other M0 patients referred from outside hospitals for immunophenotyping were also included in this study. There were two peaks in age distribution of these 16 patients: less than 3 years and between 51 and 70 years, respectively. Organomegaly was more common in patients with AML-M0 than in those with other subtypes (56.3% vs 29.2%, P = 0.025). The former patients had higher incidences of CD7 and CD34 expression on the leukemic cells than the latter ones (50% vs 16.9%, P = 0.003 and 69.2% vs 37.9%, P = 0.019, respectively). The patients with AML-M0 showed more frequent clonal chromosomal abnormalities in the leukemic cells than other AML patients (83.3% vs 53.9%, P = 0.039); the same is also true for complex cytogenetic aberrations (50% vs 11. 4%, P = 0.004). Adults with AML-M0 showed a lower complete remission (CR) rate and significantly poorer survival than those with non M0-AML. However there was no significant difference in outcome between the two groups of pediatric patients. In conclusion, AML-M0 is a unique subtype of leukemia that has distinct age distribution and shows different clinical and biological characteristics from other AML. Adult patients have poor prognosis. Whether pediatric patients had better outcome than adults needs to be clarified in further studies.

Typhoid fever presenting as infection-associated hemophagocytic syndrome: report of one case

This report describes a 13-year-old boy who had high fever with severe pancytopenia and acute psychosis as initial presentation. Bone marrow examination was compatible with infection-associated hemophagocytic syndrome (IAHS). Blood culture showed no growth of bacteria while the culture of bone marrow yielded Salmonella typhi. The clinical condition stabilized shortly after the use of ceftriaxone. This case illustrates that typhoid fever must be included in the differential diagnosis of IAHS. In cases with IAHS, bacterial culture as well as morphological study of bone marrow is necessary for the evaluation of etiological agent and to avoid injudicious use of chemotherapy.

Niemann-Pick disease type C (a cellular cholesterol lipidosis) treated by bone marrow transplantation

Bone marrow transplantation (BMT) has been used for a wide variety of lysosomal storage diseases with encouraging results. We report a 3-year 5-month-old girl with Niemann-Pick type C disease (NPC) who received an allogeneic BMT. The patient presented with repeated lower respiratory tract infections, hepatosplenomegaly, failure to thrive, and developmental delay. Chest computed tomography (CT) revealed diffuse interstitial lung infiltration. Bone marrow and liver biopsies revealed abundant lipid-filled foamy macrophages. Skin fibroblast sphingomyelinase assay revealed partial deficiency. The ability of her skin fibroblasts to esterify cholesterol was very low, and the cells stained brightly for free cholesterol. She received BMT from a healthy HLA-identical male sibling donor at the age of 2 year 6 months. Full engraftment was evidenced by repeated bone marrow sex chromosome studies. Regression of the hepatosplenomegaly, markedly reduced foamy macrophage infiltration in bone marrow, and decreased interstitial lung infiltration was noted 6 months after BMT. Her neurological status, however, deteriorated. Follow-up magnetic resonance image (MRI) revealed progressive, diffuse brain atrophy. We conclude that resolution occurred in the liver, spleen, bone marrow and lung following successful engraftment. Such a response is remarkable since the underlying problem involves a membrane receptor for cholesterol. This positive response might be due to replacement of the monocyte-phagocytic system or it may imply the existence of cross-correction in the NPC membrane receptor defect by BMT approach. Since BMT did not halt the neurological deterioration, it is unlikely to be an adequate treatment for NPC.

Decreased diversity of hepatitis C virus quasispecies during bone marrow transplantation

To elucidate the role of host immune status in the evolution and complexity of hepatitis C virus (HCV) quasispecies, three chronic HCV-infected patients who underwent bone marrow transplantation (BMT) were studied. The three transplanted patients' sera were sampled at pre-BMT, 3 months after BMT, and 12 months after BMT and the nucleotide diversity and substitution of the hypervariable region (HVR) of HCV quasispecies were analyzed. The nucleotide diversity was high at the pre-BMT period (28.2-43.4 x 10(-2) nucleotide difference/site). HVR of HCV quasispecies then became homogeneous in the first 3 months after BMT (0.11-6.40 x 10(-2) nucleotide difference/site). The nucleotide diversity of HVR at 12 months after BMT of all three patients was higher than that of 3 months after BMT but still lower than that of pre-BMT (2.09-6.40 x 10(-2) nucleotide difference/site). The analysis on nucleotide substitution rate showed a higher value between pre-BMT and 3 months after BMT (0.624-0.708 nucleotide difference/site per year) than that between 3 months and 12 months after BMT (0.072-0.127 nucleotide difference/site per year). HCV RNA titer decreased when the host had a low white cell count and increased accordingly. It was concluded that the evolution of HVR of HCV quasispecies related to the immune status of the host during BMT: after immunosuppression, an initial increase of viral populations was followed by the emergence of a dominant strain while the quasispecies gradually recovered as the immunity of the host gained its competence.

Expression and characterisation of a Plasmodium falciparum protein containing domains homologous to sarcalumenin and a tyrosine kinase substrate, eps15

We have identified in Plasmodium falciparum a novel gene encoding a putative bi-functional protein, termed PfPast-1, from genomic and cDNA libraries. Analysis indicated that the sequence encodes a 62 kDa protein of 529 amino acid residues with two distinctive domains: a sarcalumenin-like domain of approximately 320 amino acids at the amino half of the molecule, which shares homology to a major sarcoplasmic reticulum lumenal protein, sarcalumenin, and an eps15 homology domain of about 90 amino acids located at the carboxyl terminus. The eps15 homology domain, first identified in a tyrosine kinase substrate, eps15, and found in increasing numbers of mammalian proteins, has recently been suggested as a protein-protein interaction domain involved in intracellular sorting. Genomic sequences encoding similar proteins containing both the sarcalumenin-like and eps15 homology domains have been identified in humans and Drosophila. RNA blot analysis revealed the presence of a single messenger RNA transcript approximately 3.7 kb in size, which is expressed in all the developmental stages examined with the highest level in extracellular gametes followed by erythrocytic asexual stages, and the lowest in the gametocytes. In the attempt to define its biological function, we have expressed a full-length recombinant PfPast-1 protein in Escherichia coli. Specific immune serum directed against the recombinant protein recognised a approximately 55 kDa protein in the parasite lysate. Further characterisation of PfPast-1 may help in elucidation of its functions in P. falciparum.

Molecular cloning and nuclear localization of a histone deacetylase homologue in Plasmodium falciparum

Reversible acetylation of core histones plays an important role in transcriptional regulation, cell cycle progression and developmental events. The acetylation state of histones is controlled by a dynamic equilibrium between activities of histone acetylase and deacetylase enzymes. Histone deacetylase (HDAC) was recently suggested to be the target of a fungus-derived antiprotozoal agent exhibiting structural similarity to known HDAC inhibitors. We have initiated a study of HDAC of human malaria parasite, Plasmodium falciparum, to evaluate its potential as the target for novel antimalarials and its role in parasite development. We have isolated HDAC1 gene from the P. falciparum genomic and cDNA libraries. The nucleotide sequence contains no intervening sequence and its open reading frame (ORF) codes for a protein of 449 amino acid residues. We have named the protein, PfHDAC1, as the sequence shows significant homology to yeast, human and other eukaryotic HDACs. Northern blot analysis of the total RNA from different asexual and sexual stages of the parasite reveals the presence of single mRNA transcript, which is predominantly expressed in mature asexual blood stages and in gametocytes. Antiserum raised against a carboxyl terminal peptide immunoprecipitated an in vitro translated P. falciparum HDAC gene product and recognized an approximately 50 kDa protein in the Triton X-100 insoluble fraction of parasites. Immunoelectron microscopy analysis showed majority of the protein localized in the nucleus of P. falciparum. To our knowledge, this is the first HDAC gene isolated from the malaria parasite.

Longitudinal observation and outcome of nonfamilial childhood haemophagocytic syndrome receiving etoposide-containing regimens

The long-term outcome of 22 children treated with etoposide-containing regimens for haemophagocytic syndrome (HS) were longitudinally studied; none of them had a family history of the disease. All patients received etoposide-containing (150 mg/m2/d) regimens, combined, in 16 cases, with intravenous immunoglobulin (IVIG) and prednisolone. Complete remission (CR) was achieved in 12 patients, partial remission in seven, and early mortality occurred in three. Of the 12 CR patients, only four remain alive and disease-free, with a median follow-up of 47.4 months; one CR patient died due to infection and the remaining seven had relapsed diseases. Three patients with a partial response or with relapsed disease progressed to T-cell lymphoma, characterized, in the two cases tested, by clonal chromosomal abnormalities. Epstein-Barr virus (EBV) infection was implicated in disease pathogenesis in 15/22 patients. The overall survival was 45.5%, 40.9% and 40.9% at 1, 3 and 5 years, respectively, and disease-free survival for CR patients at these same times was 45.5%, 36.4% and 36.4%. The etoposide-containing regimen would appear to be an effective initial therapeutic option for childhood HS. However, in view of the frequency of partial remissions and relapsed disease, a more intensive chemotherapy or bone marrow transplantation should be applied. The progression to EBV-containing T-cell lymphoma in three patients is consistent with the previous observation that EBV-associated HS is a potentially malignant disease.

High-dose therapy with peripheral blood stem cell (PBSC) support using an innovative mobilization regimen in patients with high-risk primary or chemoresponsive metastatic breast cancers

High-dose therapy followed by peripheral blood stem cell (PBSC) support was performed in 29 patients with primary high-risk (Group I) or chemoresponsive metastatic (Group II) breast cancer patients. Group I patients had received PBSC mobilization within 4 weeks of modified radical mastectomy. Group II patients had to achieve minimal residual disease (MRD) by induction chemotherapy before being considered eligible for PBSC mobilization and high-dose therapy. An innovative FE120C regimen (5-FU 600 mg/m2, i.v., day 1; epirubicin 120 mg/m2, i.v., day 1; cyclophosphamide 600 mg/m2, i.v., day 1) plus G-CSF (300 microg/day, subcutaneous injection for 9 days, from day 4 post-FE120C) was used to mobilize PBSCs. After high-dose CTCb (cyclophosphamide 6,000 mg/m2, thiothepa 500 mg/m2, carboplatin 800 mg/m2, in 4 days), patients received PBSC infusion and daily C-CSF 300 microg subcutaneous injection. There were 19 and 16 patients enrolled into Group I and Group II, respectively. Ten of the Group II patients had achieved minimal residual disease (MRD) after induction chemotherapy. The median numbers of mobilized total CD34 + cells for Group I and Group II patients were 27.3 (9.2 to 114.1) x 10(6)/kg and 17.1 (5.9 to 69.1) x 10(6)/kg respectively. The median time to neutrophil recovery (ANC > or = 500/microL) was 8 and 9 days in Group I and II, respectively. The median time to platelet recovery (> or = 50,000/microL) was 10 and 15 days in Group I and II, respectively. No major treatment-related toxicities were noted. In Group I, 13 out of 19 patients (68.4%; 43-87%, 95% C.I.) remained recurrence-free with a median follow-up of 31 months (6 + to 55 + months). In Group II, 3 out of 10 patients (30%; 7-65%, 95% C.I.) remained progression-free at 33 +, 35 +, 39 + months from induction therapy. We suggest that the FE120C plus G-CSF is an effective and innovative regimen for PBSC mobilization in breast cancer patients, and high-dose CTCb therapy with PBSC support is a safe and well-tolerated treatment modality.

Ki-1 lymphoma in two children

Childhood Ki-1 lymphoma is rarely reported in Taiwan. We present two 8-year-old girls with Ki-1 lymphoma diagnosed and treated at the National Taiwan University Hospital. The first patient presented with a neck mass with hepatosplenomegaly. The second patient initially presented with joint pain and pathologic fracture; she was later found to have bone marrow involvement. Histologic studies of both tumors revealed bizarre large cells with pleomorphic nuclei and prominent nucleoli. All these cells were immunolabeled with monoclonal antibody Ki-1. The two patients received different polyregime chemotherapy protocols followed by bone marrow transplantation (BMT); patient 1 had autologous BMT and patient 2 had allogeneic BMT. In addition, local radiotherapy and retinoic acid were tried for patient 1 but she responded poorly and died 2 years after presentation. In patient 2, although bone marrow was initially involved, allogeneic BMT was performed smoothly after tumor loading was reduced and the patient was in remission at last follow-up, 26 months after presentation. Ki-1 lymphoma in children is characterized by clinical presentations, and histologic and immunologic findings. Aggressive polyregime chemotherapy and bone marrow transplantation are treatments for this disease.

Dilute topical proparacaine for pain relief after photorefractive keratectomy

PURPOSE

The purpose of the study is to determine whether there is a nonanesthetic and nontoxic concentration of topical proparacaine that can be applied repeatedly to the cornea to reduce pain after photorefractive keratectomy (PRK).

METHODS

Part I: To determine a nonanesthetic concentration, the corneal sensitivity of 50 healthy volunteers was assessed using aesthesiometry before and after a drop of either 0.01%, 0.025%, 0.05%, 0.1%, or 0.2% topical proparacaine. Ten volunteers similarly were tested with multiple doses of 0.05% proparacaine. To evaluate toxicity, ten healthy volunteers self-administered 0.05% proparacaine to one eye and placebo to the other eye every 15 minutes for 12 hours on day 1 and every hour for 12 hours on days 2 through 7. Subjects were assessed throughout the week using visual acuity, slitlamp examination, aesthesiometry, and ultrasonic pachometry. Part II: In a prospective, double-masked study, 34 patients who underwent PRK (48 eyes) self-administered either topical 0.05% proparacaine or placebo for 1 week after PRK as needed to reduce pain. Patients recorded their pain score before and after drop use and answered a pain-relief questionnaire.

RESULTS

Part I: Proparacaine concentrations greater than or equal to 0.1% eliminated sensation from some corneas; concentrations of less than or equal to 0.05% were never fully anesthetic. No corneal toxicity was observed except for some minimal punctate staining in both treatment and placebo eyes. Part II: Patients in the treatment group had significantly more pain relief (P < 0.001) for a longer period (P < 0.001) than did patients in the control group. Average change in pain score was significantly greater in the treatment group (P < 0.002). No significant difference in the number of days needed to reach complete epithelial healing was found between the two groups (P < 0.18).

CONCLUSIONS

Dilute (0.05%) topical proparacaine is nonanesthetic and nontoxic, and can be used safely for at least 1 week to reduce pain after PRK.

Allogeneic bone marrow transplantation for Philadelphia chromosome-positive chronic myelogenous leukemia in childhood

Allogeneic bone marrow transplantation (BMT) offers the only potential for long-term control of chronic myelogenous leukemia. From November 1992 to August 1994, we prospectively studied five pediatric patients with Philadelphia chromosome-positive chronic myelogenous leukemia, a unique finding in Taiwan, who were treated with allogeneic BMT at different stages of the disease. Their ages at diagnosis ranged from 2 to 10 years. Four donors were HLA-matched siblings and the other was an HLA-matched unrelated donor. All patients received busulfan (4 mg/kg/day for 4 days) followed by cyclophosphamide (60 mg/kg/day for 2 successive days) as the conditioning regimen. Engraftment was documented within 22 days after transplantation in all five patients. Two out of the four patients in the sibling donor group, both of whom had BMT in the first chronic phase, achieved event-free survival after follow-up for 41 months and 17 months. The other two patients, who had BMT in the second lymphoblastic crisis and the second chronic phase, died within 6 months after transplantation due to lymphoid blastic crisis and complication of cytomegaloviral pneumonitis, respectively. The patient who received marrow from the unrelated donor underwent BMT in the accelerated phase and died within 6 months after transplantation due to myeloid blastic crisis. In conclusion, allogeneic BMT performed in the first chronic phase of childhood Philadelphia chromosome-positive chronic myelogenous leukemia seems to have better results than BMT after the first chronic phase.

In vitro evaluation of the effects of transportation and storage on platelet concentrates

Platelets may be activated and become acidic during transportation and storage, resulting in poor post-transfusion platelet survival and recovery. In this study, we evaluated the current local shipment protocol for platelet concentrates and the storage technique used at the National Taiwan University Hospital. Platelet concentrates were transported routinely in cardboard boxes at ambient temperature. They were then stored in an agitator at 20 degrees C to 24 degrees C in the blood bank. We measured changes in beta-thromboglobulin, pH, platelet distribution width (PDW) and platelet counts before and after shipment and storage. The level of beta-thromboglobulin reflects platelet activation and was determined by enzyme immunoassay. The beta-thromboglobulin levels and platelet counts were not significantly different after transportation and during the storage period but there were significant changes in pH and PDW after storage (p < 0.001). Regression study showed that the prestorage platelet counts and pH were strongly associated with the pH at the end of storage (r = -0.71, r = 0.75 respectively). We concluded that the current shipment technique has no adverse effect on the in vitro characteristics of platelets, and the prestorage pH and platelet count could be used as predictors for the pH at end of storage. The data indicate that it is important to measure the prestorage pH and platelet count to set up an optimal storage strategy.

Cord blood transplantation for acute lymphoblastic leukemia in a pediatric patient

The prognosis of Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) is poor. While umbilical cord blood transplantation has been used successfully for hematopoietic reconstitution, patients' size may be a limiting factor. We report an 11-year-old, 55-kg patient with Ph+ ALL, who received human leukocyte antigen-identical sibling donor cord blood transplantation (5.94 x 10(6) CD34+ cells) during the second ALL relapse. On days 25, 41, 75 and 103, successful engraftment was confirmed by cytogenetic studies. However, the leukemia relapsed on day 117 and the patient died on day 146 due to refractory ALL. In conclusion, based on the documented engraftment in our patient, we believe cord blood transplantation may be successfully employed in adolescent or possibly even adult patients.

MRI of pulmonary embolism using Gd-DTPA-polyethylene glycol polymer enhanced 3D fast gradient echo technique in a canine model

This study was to evaluate the accuracy of MR angiography (MRA) using a Gd-DTPA-polyethylene glycol polymer (Gd-DTPA-PEG) with a 3D fast gradient echo (3D fgre) technique in diagnosing pulmonary embolism in a canine model. Pulmonary emboli were created in six mongrel dogs (20-30 kg) by injecting tantalum oxide-doped autologous blood clots into the femoral veins via cutdowns. MRI was performed with a 1.5 T GE Signa imager using a 3D fgre sequence (11.9/2.3/15 degrees) following intravenous injection of 0.06 mmol Gd/kg of Gd-DTPA-PEG. The dogs were euthanized and spiral CT of the lungs were then obtained on the deceased dogs. The MRI images were reviewed independently and receiver-operating-characteristic (ROC) curves were used for statistical analysis using spiral CT results as the gold standard. The pulmonary emboli were well visualized on spiral CT. Out of 108 pulmonary segments in the six dogs, 24 contained emboli >2 mm and 27 contained emboli < or = 2 mm. With unblinded review, MRI detected 79% of emboli >2 mm and only 48% of emboli < or = 2 mm. The blinded review results were significantly worse. Gd-DTPA-PEG enhanced 3D fgre MRI is potentially able to demonstrate pulmonary embolism with fairly high degree of accuracy, but specialized training for the interpretations will be required.

High frequency of HLA-A*0207 subtype in Chinese population

BACKGROUND

HLA-A2 is the most polymorphic and most common HLA phenotype found in various ethnic populations. Seventeen HLA-A2 subtypes have been reported and characterized by molecular techniques. Differences among these subtypes are limited to a few amino acids. Among them, HLA-A*0201 is the predominant subtype among whites. The results of a recent study, however, suggest that the HLA-A*0207 subtype may be present at a high frequency in the Chinese population.

STUDY DESIGN AND METHODS

To determine the exact frequency of the HLA-A*0207 subtype in the Chinese population, genomic DNA samples obtained from 54 HLA-A2-positive Chinese in Taiwan were studied by using sequence-specific primers and polymerase chain reaction.

RESULTS

HLA-A*0207 was present in 56 percent of the studied subjects. The estimated gene frequency for HLA-A*0207 is 17.8 percent in the Chinese population.

CONCLUSION

HLA-A*0207 is the most common HLA-A2 subtype among Chinese. The high frequency of the HLA-A*0207 allele in this population offers a unique opportunity to study the ways in which different HLA-A2 subtypes may influence the clinical outcome of allograft transplantation and the disease susceptibility of recipients.

Can severe neonatal jaundice be prevented by neonatal screening for glucose-6-phosphate dehydrogenase deficiency?--a review of evidence

An evidence-based approach is used to evaluate the neonatal screening program for glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. The primary consideration to include G-6-PD deficiency (G-6-PDD) in neonatal screening program was the public health burden of G-6-PDD-associated neonatal jaundice (G-6-PDDANJ) in the target population. However, the prevalence of G-6-PDD per se cannot be the sole index of the public health burden of G-6-PDDANJ. In more developed areas, G-6-PDDANJ is no longer a major public health problem. Further, most cases with G-6-PDDANJ in more developed areas are not precipitated by any identifiable icterogenic agents, and therefore not preventable by avoidance education. In less developed areas, however, G-6-PDDANJ is still a big public health burden and requires intervention. In this study, the effectiveness of neonatal screening programs for G-6-PDD to prevent severe neonatal jaundice(NJ) has been shown based on historical comparison, but the results may be confounded by other temporal factors. G-6-PDDANJ usually occurs in the first week after birth. Prompt need for G-6-PD screening results precludes it from incorporation into other existent neonatal screening programs (i.e., for PKU), and from centralization of laboratory work. The efficacy, adverse effects and cost-effectiveness of this mass screening program need further study.

Stage-specific expression of a Plasmodium falciparum protein related to the eukaryotic mitogen-activated protein kinases

We have identified a putative protein kinase gene from both Plasmodium falciparum cDNA and genomic DNA libraries. The nucleotide sequence contains an open-reading frame of 2646 bp, which codes for a predicted protein of 882 amino acid residues. Comparison of the predicted amino acid sequence with those in GenBank suggests that this gene codes for a protein similar to the mitogen-activated protein (MAP) kinase of other organisms. This MAP kinase-related protein, named PfMRP, contains the TDY dual phosphorylation site upstream of the highly conserved VATRWYRAPE sequence in subdomain VIII. PfMRP contains an unusually large and highly charged domain within its carboxyl-terminal segment, which includes two repetitive sequences of either a tetrapeptide or octapeptide motif. PfMRP gene is located on chromosome 14. Northern blot analysis of total RNA reveals the presence of a single mRNA transcript approximately 4.2 kb in length, which is predominantly expressed in gametocytes and gametes/zygotes.

N-allylsecoboldine as a novel antioxidant against peroxidative damage

N-Allylsecoboldine was evaluated for antioxidant properties by studying its ability to react with relevant reactive oxygen species, and its protective effect on human erythrocytes under oxidative stress. Using brain homogenates, we found that N-allylsecoboldine dose dependently inhibited lipid peroxidation (IC50 = 4.80 +/- 0.16 microM) and markedly scavenged stable nitrogen-centered radicals. N-Allylsecoboldine was a very efficient scavenger for inhibiting peroxyl radical-mediated destruction of B-phycoerythrin, with a stoichiometry factor of 4.40 +/- 0.59. It also trapped the hydroxyl radicals with a second-order rate constant of 6.92 +/- 0.86 x 10(9) M-1 S-1. Additionally, human erythrocyte oxidative hemolysis induced by aqueous peroxyl radical or hydrogen peroxide was suppressed by N-allylsecoboldine. It not only attenuated the extent of lipid peroxidation but also decreased the formation of the high-molecular weight proteins and degradation of the band 6 protein in radical-treated erythrocytes. It also inhibited the shortening of Russell's viper venom-clotting time mediated by prelytic radical-treated erythrocytes. In the presence of exogenous oxidative stress, hemolysis and lipid peroxidation were significantly enhanced in beta-thalassemic erythrocytes, as compared to the normal control. These elevated detrimental effects could be prevented by N-allylsecoboldine. It is concluded that N-allylsecoboldine may act as an effective antioxidant and protect cells against oxidative damage.

Hemolytic disease of the newborn caused by anti-M antibody

An unusual case of hemolytic disease of the newborn caused by anti-M antibody is presented. Hyperbilirubinemia was noted in a full-term baby boy at 4 days of age. A total of 160 mL of M-positive packed red blood cells from the baby's father were transfused during the next 9 days and the hemolytic process became aggravated. The baby was referred to our hospital at 14 days of age. Maternal anti-M was detected and the baby was transfused with 50 mL of M-negative packed red blood cells. The baby's condition stabilized and he was discharged uneventfully at 18 days of age.

Hepatitis C viral infection in thalassemic children: clinical and molecular studies

To determine and correlate the liver function profile, hepatitis C virus (HCV) genome, anti-HCV, genotypes, quantitation, and nucleotide sequence variability in polytransfused thalassemic children, 61 such children were studied prospectively for 4 y. Twenty-six had HCV infection. The average age, number of transfusions, and alanine aminotransferase (ALT) levels of the HCV-infected group were higher than those of the 35 children without HCV infection. None was infected after the initiation of anti-HCV screening in donor blood. Liver biopsies were performed in six HCV-infected and eight HCV-noninfected thalassemic children, and portal fibrosis was found more frequently in the HCV-infected group. Quantitation of HCV RNA was done by the competitive polymerase chain reaction method, and the titer was about 1 x 10(6) to 5 x 10(8) copies/mL. The titer did not change significantly over the 4-y follow-up period and did not correlate with ALT levels. Nineteen HCV-infected patients were genotyped; 15 were Okamoto/Simmonds type II/1b, two were type III/2a, and two were type IV/2b. The hypervariable region of the HCV genome (E2/NS1) was cloned and sequenced in two serum samples from one patient collected at a 2-y interval, as the ALT levels decreased. The variation rate was estimated to be 1.2-1.7 x 10(-2)/nucleotide/y. The results showed that, in polytransfused thalassemic children, 43% (26/61) contracted HCV. We conclude that HCV infection may cause elevated ALT levels and portal fibrosis of the liver, whereas the viral titer and genotypes do not parallel ALT levels.

Correlation of cytogenetic results with immunophenotype, genotype, clinical features, and ras mutation in acute myeloid leukemia. A study of 235 Chinese patients in Taiwan

Of 235 consecutive patients with de novo acute myeloid leukemia (AML), clonal chromosomal abnormalities were detected in 151 (64%) of them. Twenty-four of the 71 patients with M2 AML had t(8;21), 35 of the 36 M3 patients had t(15;17), and 11 of the 45 M4 leukemia disclosed inv(16). Six of the eight patients with 11q23 abnormality had M4 or M5 subtype of leukemia. The incidence of t(15;17) and t(8;21) was higher in our patients than in patients from most Western countries. Immunophenotyping was performed on 197 patients. Patients with t(15;17) were associated with negativity to HLA-DR, CD11b, and CD34. Patients with t(8;21) expressed CD13 and CD33 less frequently than other patients, but all showed CD15 positivity. Coexpression of lymphoid-associated antigens on the leukemic blasts was detected in 52 patients (26%), including all 7 patients with t(9;22), 3 of the 8 patients with t/del(11)(q23), 2 of the 25 patients with t(15;17), and 2 of the 22 patients with t(8;21). Seven (35%) of the 20 patients coexpressing lymphoid markers showed immunoglobulin heavy chain or T-cell receptor beta-chain gene rearrangements, while only 2 (4%) of the 53 patients without lymphoid antigen expression did so. Patients with inv(16), t(8;21), and t(15;17) had a better prognosis than other patients. Of all surface antigens tested, only CD15, CD11b, and HLA-DR were of prognostic value: CD15 with a higher complete remission (CR) rate and CD11b or HLA-DR with a shorter CR duration. N-ras mutations were detected in 7 (18%) of the 40 patients in the study, including two of the three patients with inv(16). This study demonstrated differences in clinical features, immunophenotypes, and genotypes among different cytogenetic subgroups.

Acute leukemic transformation of myelodysplastic syndrome--immunophenotypic, genotypic, and cytogenetic studies

The clinical and biological characteristics of myelodysplastic syndrome (MDS) in acute leukemic transformation were studied in 23 patients. All had myeloid transformation according to FAB criteria, but coexpression of lymphoid-associated antigens was detected in five of the 20 patients who underwent an immunophenotypic study. Rearrangement of the immunoglobulin heavy chain gene was also observed in one of the five patients who coexpressed lymphoid markers and that of the T-cell receptor beta chain gene in another one. None had pure lymphoid transformation. Clonal chromosomal abnormalities were noted in 12 (63%) of the 19 patients who underwent cytogenetic study, most commonly - 7 (six patients or 32%). In the 18 patients who underwent serial analyses both at MDS diagnosis and at acute transformation, seven (39%) underwent karyotypic evolution. The most common new or additional aberrations were +8 and +21. N-ras gene mutation was detected in two of the nine patients at acute leukemic transformation. The median interval from diagnosis of MDS to onset of acute transformation was 10 months (1-36 months). Patients with a normal karyotype at diagnosis had a significantly longer chronic phase duration than those with chromosomal abnormalities (median of 20 months vs. 5 months). However, all had a short survival time after diagnosis of acute leukemia, whether chromosomal anomalies were present or not.

Recombinant alpha-interferon treatment of intracranial hemangioma and Kasabach-Merritt syndrome in an infant with cytomegalovirus

A 2-month-old girl presented with enlarged head girth, generalized petechiae, anemia, coagulopathy and hepatosplenomegaly. Imaging studies showed a huge, dumbbell-shaped intracranial hemangioma located between the falx, and involving the supra- and infra-tentorium, extending through the posterior fontanel to involve the subgaleal area. A urine culture grew cytomegalovirus. Severe thrombocytopenia was refractory to a massive platelet transfusion, intravenous immunoglobulin and corticosteroid therapy. Hypertension, pulmonary hemorrhage and sepsis complicated the course. After establishing a diagnosis of Kasabach-Merritt syndrome, subcutaneous injections of alpha-interferon were given with an initial dose of 1 x 10(6) IU/m2 followed by 3 x 10(6) IU/m2 per day for 12.5 mo. Her platelet count rose gradually and became stable after 1.5 mo of interferon treatment. The intracranial hemangioma regressed remarkably and the hepatosplenomegaly was also resolved. The infant showed good growth and development, without obvious side-effects during the 23-month follow-up period. The treatment with recombinant alpha-interferon appeared to be effective in reversing thrombocytopenia associated with the patient's massive intracranial hemangioma.

Immunomodulation treatment for childhood virus-associated haemophagocytic lymphohistiocytosis

The Epstein-Barr virus (EBV), or human herpesvirus-6 (HHV-6) associated haemophagocytic lymphohistiocytosis, has been found prevalent in Taiwan; it affects previously healthy children and is always fatal when treated only supportively. Recognition of the underlying pathogenesis for this disease prompted adoption of an immunomodulatory regimen of intravenous immunoglobulin (IVIG) and/or etoposide on 17 such patients treated between 1990 and 1993. Remarkable improvement in patients' prognoses was demonstrated. Eight patients are still alive with a median follow-up of 1 year and 2 months post-treatment. Both IVIG and etoposide had positive immunomodulation effects such as alleviation of fever and normalization of haematological and hepatic parameters. Sustained complete response was obtained in two of nine cases of EBV-associated diseases treated with IVIG only. EBV transcripts became undetectable after etoposide and/or IVIG treatment without antiviral agents. Etoposide given by split-doses schedule appeared to be superior to conventional three-consecutive-days schedule for both remission induction and disease-free survival. Our preliminary trial apparently provides a promising improvement in the treatment of this previously fatal disease. IVIG or etoposide is effective in reversing the process of lymphohistiocytic dysregulation resulting from virus infection of immune cells in this syndrome and probably helps hosts to control active virus replication in certain cases, through immunomodulation.

Oxygen saturation of blood in the superior mesenteric vein: in vivo verification of MR imaging measurements in a canine model. Work in progress

PURPOSE

To evaluate the accuracy of magnetic resonance (MR) imaging in estimating oxygen saturation of blood (%HbO2) in the superior mesenteric vein (SMV) of a canine model in vivo.

MATERIALS AND METHODS

MR imaging was used to measure the T2 of blood in samples obtained via a catheter placed in the SMV in seven mongrel dogs. %HbO2 was measured with a reflectance oximeter. These measurements were obtained at the resting state, during superior mesenteric artery occlusion, and after reperfusion. MR imaging and oximeter measurements were then compared by using linear regression analysis.

RESULTS

Refocusing intervals (tau 180) of 12 and 24 msec were used for 17 and 18 %HbO2 measurements with MR imaging, respectively. With tau 180 of 12 msec, there was an excellent correlation between MR imaging measurements and oximeter measurements (r = .969). The intercept was 5.3% and the slope was 0.959. With tau 180 of 24 msec, r = .953, the intercept was 15.4%, and the slope was 0.817.

CONCLUSION

Estimates of %HbO2 in the SMV with MR imaging are accurate in the range of most clinical interest.

Allogeneic bone marrow transplantation for children with acute lymphoblastic leukemia in second remission or relapse

Most children with acute lymphoblastic leukemia (ALL) are successfully treated by chemotherapy. For those patients, who relapse on therapy, bone marrow transplantation (BMT) is considered most appropriate after a subsequent remission is achieved. Three boys with ALL aged from 9 to 13 years met these criteria and received BMT from their HLA-compatible sisters after marrow ablation with total body irradiation 12 Gy plus high dose cytosine arabinoside 3 gm/m2/12h x 12 doses and graft-versus-host disease (GVHD) prophylaxis with cyclosporine plus short course methotrexate from March 10, 1989 to May 23, 1992. Filgrastim (rhG-CSF) was used to hasten the recovery of granulocyte in one patient. All three patients got full engraftment and two had grade 1 acute GVHD. None of them developed chronic GVHD. Two patients have disease-free survival over 51 and 12 months respectively post BMT without further chemotherapy. One patient died of recurrent refractory leukemia 5 months after BMT. The toxicity of this conditioning regimen included photophobia, conjunctivitis and erythematous skin rashes. One patient who received filgrastim from day 1 to 21 developed severe bone pain. However, this patient had faster recovery of granulocyte count than the other two patients. The preliminary results of this work favors BMT for children with recurrent ALL whose ultimate survival is usually poor when treated with chemotherapy. Further efforts are necessary to investigate new methods for reducing leukemic relapse in ALL patients undergoing BMT.

Pyogenic liver abscess in beta-thalassemia major--report of two cases

Pyogenic liver abscess, which may lead to devastating consequences, is an uncommon medical problem in pediatrics and has generally been reported in compromised hosts. This article describes two patients with beta-thalassemia major and hemochromatosis complicated by Klebsiella pneumoniae liver abscess. One of the patients had severe complications, including subphrenic abscess, pleural effusion and meningitis. To present knowledge, the occurrence of K. pneumoniae liver abscess in patients with beta-thalassemia major has never before been reported in the literature.

Bone marrow transplantation for childhood acute myelogenous leukemia

Six consecutive patients with acute myelogenous leukemia (AML) underwent 7 allogeneic bone marrow transplants at National Taiwan University Hospital. Marrow ablation for 4 patients consisted of busulfan 16 mg/kg and cyclophosphamide 120 mg/kg (BUCY 2). Two patients had busulfan 16 mg/kg and cyclophosphamide 200 mg/kg (BUCY 4) as marrow ablation. One had a second transplant following cytosine arabinoside 3 gm/m2/dose x 10 doses plus total body irradiation 12 Gy. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and short course methotrexate. Four patients received marrow from their HLA compatible siblings and two from their HLA-haplotype-matched fathers. Four transplants were performed during first remission and the other three during subsequent remission or relapse. All patients except one engrafted and achieved a complete remission (CR). Three of 4 patients transplanted in first CR are alive for over 10, 20 and 59 months respectively after transplant. One of the two patients who each received marrow from their fathers during 2nd CR and relapse, developed relapse 5 months later and the other developed aplasia 3 months later. Acute GVHD occurred in two of six patients. Localized chronic GVHD occurred in one of these two patients. Toxicities of BUCY 2 were minimal except veno-occlusive disease. One patient who received BUCY 4 developed hemorrhagic cystitis. There were no treatment related deaths except one patient who received 2nd transplant. These results demonstrate that BUCY 2 should be considered as a preparative regimen for allogeneic bone marrow transplantation for patients with AML in first remission.(ABSTRACT TRUNCATED AT 250 WORDS)

Corneal topographic analysis after excimer photorefractive keratectomy

BACKGROUND

A 2-year experience with corneal topography after photorefractive keratectomy (PRK) is reported, specifically reviewing the correlation of surface regularity index versus best spectacle-corrected visual acuity as a function of various ablation patterns. Centration and stability issues also are discussed.

METHODS

Excimer laser PRK for myopia was performed on 502 consecutive eyes. Corneal topographic analysis was performed at the 1-, 3-, 6-, and 12-month postoperative follow-up visits. In all patients, PRK was performed with an argon fluoride laser, and a topographic analysis was done.

RESULTS

Topographic analysis at the first postoperative month was useful for determining decentration of the optical zone. The mean decentration from the pupillary center for all eyes was 0.34 mm. Four main patterns of ablation were noted by subtraction analysis. At the 1-month postoperative examination, a "uniform" ablation was present in 44% of eyes, "keyhole" ablations were present in 12% of eyes, "semicircular" ablations were present in 18% of eyes, and an unusual "central island" was present in the remaining 26% of eyes. However, on subsequent follow-up the central islands tended to resolve with time. At 3 months postoperatively, 18% of eyes in that group showed a central island, 8% showed a central island at 6 months, and only 2% of eyes showed a central island at the 12-month postoperative visit. Correlation of central island topography with visual acuity and progressive hyperopia are discussed.

CONCLUSIONS

Corneal topography is essential for evaluating surface changes after excimer PRK. The surface regularity index is a good indicator of best spectacle-corrected visual acuity and is used to evaluate irregular astigmatism after PRK. Central island topographies are correlated with poor initial visual rehabilitation. Long-term stability issues are answered with continued topographic follow-up. Understanding corneal hydration changes between the central and peripheral cornea may help us understand the etiology of central islands.

Epstein-Barr virus (EBV) infects T lymphocytes in childhood EBV-associated hemophagocytic syndrome in Taiwan

We have reported the prevalence of a fulminant hemophagocytic syndrome (HS) in previously healthy young children in Taiwan, most of which probably represent a lethal form of primary or active Epstein-Barr virus (EBV) infection. To further confirm their EBV association, in situ EBV hybridization (ISH) was performed on tissue biopsies from 15 pediatric HS patients (median age, 3 years and 4 months) using digoxigenin-labeled RNA probes EBER1. Double labeling immunostaining and ISH was then performed to define the immunophenotype of the lymphoid cells containing the EBV transcripts. Among the 13 patients who had serological evidence of acute or active EBV infection, 9 had demonstrable EBER1 transcripts in bone marrow, liver, and/or skin biopsies. EBER1-specific signal was not detectable in the two specimens from EBV-seronegative patients. The distribution of EBV-containing cells could be extensive or scattered. To our surprise, the EBER1 transcripts existed exclusively in T lymphoid cells in all nine cases examined rather than in B cells as previously believed in infectious mononucleosis. Considering the young affected age of the HS patients and the serological response to EBV, we suggest that EBV can infect T cells in primary EBV infection and the proliferation of these EBV-infected T cells may be responsible for the ominous outcome in childhood HS patients in Taiwan.

Findings of magnetic resonance and colour-flow Doppler imaging of orbital embryonal rhabdomyosarcoma

The authors describe a case of embryonal rhabdomyosarcoma of the orbit evaluated with magnetic resonance imaging (MRI) and colour-flow Doppler imaging. MRI demonstrated a markedly enhancing tumour with no discrete vessels. Colour-flow Doppler ultrasonography showed evidence of perfusion; however, discrete vascular channels were difficult to visualize, and no evidence of large vessels within the tumour was found at surgery. The differential diagnosis of this condition is discussed, as well as the potential role of colour-flow Doppler imaging in the assessment of orbital tumours, a role in which this method has not yet been widely applied.