Imipramine Suppresses Tumor Growth and Induces Apoptosis in Oral Squamous Cell Carcinoma: Targeting Multiple Processes and Signaling Pathways

BACKGROUND/AIM

Oral squamous cell carcinoma (OSCC) has limited treatment options. This study investigated imipramine, a tricyclic antidepressant, as a potential therapy for OSCC using a SAS-bearing xenograft animal model.

MATERIALS AND METHODS

The SAS-bearing xenograft model evaluated imipramine's impact on tumor growth. The control group received no treatment, while the imipramine-treated group received regular doses. Tumor growth, confirmed by imaging, and histological analysis assessed size and weight. Imipramine's effects on apoptosis, epithelial-to-mesenchymal transition (EMT), and transcription factors (AKT, ERK, STAT3) were analyzed.

RESULTS

Imipramine significantly suppressed tumor growth within 6 days of treatment, with sustained activity. Computer tomography (CT) scans and histology confirmed reduced size and weight by imipramine. Imipramine induced apoptosis via caspase-dependent/-independent pathways, inhibited EMT, and down-regulated phosphorylated AKT, ERK, and STAT3.

CONCLUSION

Imipramine shows promise as an effective OSCC therapy, inhibiting tumor growth, inducing apoptosis, and inhibiting EMT. Its impact on transcription factors and modulation of the AKT/ERK/STAT3 pathway suggest a multifaceted approach.

Amentoflavone induces caspase-dependent/-independent apoptosis and dysregulates cyclin-dependent kinase-mediated cell cycle in colorectal cancer in vitro and in vivo

Colorectal cancer (CRC) is recognized as the third most common malignancy and the second most deadly in highly developed countries. Although the treatment of CRC has improved in the past decade, the mortality rate of CRC is still increasing. Amentoflavone, one of the flavonoids detected in medical plants, is reported to possess potential anticancer properties in various cancers. However, its role in CRC has not been studied. This study aimed to investigate the role and underlying mechanism of amentoflavone on CRC in vitro and in vivo. We identified the cytotoxicity, apoptosis effect, cell cycle alteration, DNA damage induction and tumor progression inhibition of amentoflavone in HT-29 model by using MTT assay, flow cytometry, immunofluorescence (IF) staining, Western blotting and animal experiments. Amentoflavone induced cytotoxicity is caused by triggering G1 arrest, DNA damage and apoptosis in HT-29 cells. The expression of cyclin D1, CDK4 and CDK6 was decreased by amentoflavone; in contrast, the phosphorylation of ATM and CHK2 and the expression of p21 and p27 were increased. The apoptosis induction of amentoflavone in CRC is not only caspase-dependent but also increases EndoG and AIF nuclear translocation in a caspase-independent manner. Importantly, the apoptosis induction of amentoflavone is not affected by the activity of p53 in CRC. Amentoflavone suppressed the progression of CRC by initiating G1 arrest and ATM/CHK2-mediated DNA damage-responsive, caspase-dependent/independent apoptotic effects. We uncovered a novel tumor-inhibitory role of amentoflavone in CRC that is not associated with p53 activity, which may serve as a potential treatment for CRC.

Hyperforin Induces Apoptosis Through Extrinsic/Intrinsic Pathways and Inhibits NF-ĸB-modulated Survival and Invasion Potential in Bladder Cancer

BACKGROUND/AIM

Muscle-invasive bladder cancer (MIBC) has long been recognized as a difficult to treat cancer type, thus a new treatment strategy is needed. The major purpose of the present study was to verify the anticancer effect of hyperforin and the mechanism through which it affects tumor cell growth and invasion in bladder cancer in vitro.

MATERIALS AND METHODS

Bladder cancer TSGH-8301 cells were treated with different concentrations of hyperforin for different durations of time. The changes in cell viability, production of calcium and reactive oxygen species (ROS), and anti-apoptotic signaling were evaluated using MTT assay, flow cytometry, and western blot analysis. The effect of hyperforin on the expression of nuclear factor-kappaB (NF-ĸB) p65 (Ser276), tumor progression-associated proteins, as well as on cell invasion was investigated using western blotting and cell invasion assay, respectively.

RESULTS

Hyperforin significantly induces apoptosis, extrinsic/intrinsic apoptotic signaling, accumulation of cytosol ROS, and calcium signalling. Hyperforin also significantly diminishes the expression of NF-ĸB p65 (Ser276), anti-apoptotic and tumor progression-associated proteins, as well as the cell invasion ability of TSGH-8301 cells.

CONCLUSION

Our findings demonstrate that hyperforin triggers apoptosis depending on extrinsic/intrinsic pathways and suppresses NF-ĸB-mediated cell survival as well as the invasive properties of bladder cancer in vitro.

Rapidly increasing liver progenitor cell numbers in human regenerating liver after portal vein ligation and liver partition

BACKGROUND

Liver regeneration is dependent on the proliferation of hepatocytes. Hepatic progenitor cells are intra-hepatic precursor cells capable of differentiating into hepatocytes or biliary cells. Although liver progenitor cell proliferation during the regenerative process has been observed in animal models of severe liver injury, it has never been observed in vivo in humans because it is unethical to take multiple biopsy specimens for the purpose of studying the proliferation of liver progenitor cells and the roles they play in liver regeneration. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a staged procedure for inducing remnant liver hypertrophy so that major hepatectomy can be performed safely. This staged procedure allows for liver biopsy specimens to be taken before and after the liver begins to regenerate.

CASE PRESENTATION

The liver progenitor cell proliferation is observed in a patient undergoing ALPPS for a metastatic hepatic tumour. Liver biopsy is acquired before and after ALPPS for the calculation of average number of liver progenitor cell under high magnification examination by stain of immunomarkers. This is the first in vivo evidence of growing liver progenitor cells demonstrated in a regenerating human liver.

Measurement of body joint angles for physical therapy based on mean shift tracking using two low cost Kinect images

Range of motion (ROM) is commonly used to assess a patient's joint function in physical therapy. Because motion capture systems are generally very expensive, physical therapists mostly use simple rulers to measure patients' joint angles in clinical diagnosis, which will suffer from low accuracy, low reliability, and subjective. In this study we used color and depth image feature from two sets of low-cost Microsoft Kinect to reconstruct 3D joint positions, and then calculate moveable joint angles to assess the ROM. A Gaussian background model is first used to segment the human body from the depth images. The 3D coordinates of the joints are reconstructed from both color and depth images. To track the location of joints throughout the sequence more precisely, we adopt the mean shift algorithm to find out the center of voxels upon the joints. The two sets of Kinect are placed three meters away from each other and facing to the subject. The joint moveable angles and the motion data are calculated from the position of joints frame by frame. To verify the results of our system, we take the results from a motion capture system called VICON as golden standard. Our 150 test results showed that the deviation of joint moveable angles between those obtained by VICON and our system is about 4 to 8 degree in six different upper limb exercises, which are acceptable in clinical environment.

Comparative proteomic analysis of cauliflower under high temperature and flooding stresses

High-temperature and waterlogging are major abiotic stresses that affect the yield and quality of cauliflower. Cauliflower cultivars 'H41' and 'H69' are tolerant to high temperature and flooding, respectively; however, 'H71' is sensitive to both stresses. The objectives of this study were to identify the proteins that were differentially regulated and the physiological changes that occurred during different time periods in 'H41', 'H69', and 'H71' when responding to treatments of flooding, 40 °C, and both stresses combined. Changes in the leaf proteome were analyzed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and identified by Mascot peptide mass fingerprint (PMF) and database searching. Stress treatments caused significant reductions in electrolyte leakage, chlorophyll fluorescence Fv/Fm, chlorophyll content, and water potential as stress times were prolonged. By the comparative proteomic analysis, 85 protein peaks that were differentially expressed in response to combination treatments at 0, 6, and 24 h, 69 (33 in 'H41', 29 in 'H69', and 9 in 'H71') were identified, of which were cultivar specific. Differentially regulated proteins predominantly functioned in photosynthesis and to a lesser extent in energy metabolism, cellular homeostasis, transcription and translation, signal transduction, and protein biosynthesis. This is the first report that utilizes proteomics to discover changes in the protein expression profile of cauliflower in response to heat and flooding.

Haematopoietic stem cell transplantation in Taiwan: past, present, and future

In Taiwan, haematopoietic stem cell transplantation (HSCT) has been used to treat patients with haematological diseases since 1983. Thereafter till 2007, there were 2537 patients who had undergone HSCT in more than 15 hospitals. Their diseases included acute myeloid leukaemia in 27.8% of cases, non-Hodgkin's lymphoma 23.3%, acute lymphoblastic leukaemia 12.8%, chronic myeloid leukaemia 11.9%, severe aplastic anaemia 8.7%, and multiple myeloma 4.1%. Most of the cases received myeloablative conditioning regimens. More than 15% of cases received non-myeloablative regimens, and the mean age of these cases was at least 10 years older than those who received myeloablative regimens. The types of graft included peripheral blood (60.4%) and bone marrow (32.0%). A total of 35% of patients received autologous grafts. Of 1557 allogeneic HSCT patients, 338 (21.7%) received grafts from unrelated donors. Cord blood transplantation has been successfully performed in paediatric patients with thalassaemia major and with a large body size, and adult patients. The incidence of acute graft-versus-host disease was relatively low in Taiwan. On the contrary, a relatively higher proportion of hepatitis B carrier in the recipients had led to a higher incidence of reactivation hepatitis, which was markedly decreased following lamivudine prophylaxis. In conclusion, HSCT has become a routine therapy for major medical centres in Taiwan. Our unique experiences in the past decades also contributed to the progress of HSCT. With the establishment of professional association and patient supportive groups, we hope we can fully improve our daily practice and clinical as well as basic research in HSCT.

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.

Persistent knee instability following revision total knee arthroplasty

Instability is an important cause of failure following total knee arthroplasty (TKA). Knee stability needs to be optimal in both the coronal and sagittal planes. We describe failed revision TKA with persistent deformity and instability secondary to a deficient medial collateral ligament in a 71-year-old Chinese woman. Revision knee arthroplasty using constrained implants was performed on her with good result. During both primary and revision TKA, assessment of knee stability is critical. Constrained prosthesis would need to be considered when there is significant ligamentous deficiency.

Physical activity is related to lower levels of pain, fatigue and depression in individuals with spinal-cord injury: a correlational study

STUDY DESIGN

This was a prospective cross-sectional study for people with chronic spinal cord injury (SCI).

OBJECTIVES

To (1) evaluate the intensity level and nature of physical activity in community-dwelling individuals living with SCI, and (2) explore the relation between descriptive individual variables (for example, lesion level), secondary complications and participation in physical activity.

SETTING

Urban community setting.

METHODS

A total of 49 subjects with SCI who used a manual wheelchair for primary mode of mobility (mean years since injury, 11.8; mean age, 43.7 years; 67% paraplegia) completed the physical activity recall assessment for people with SCI (PARA-SCI).

RESULTS

Approximately 50% of reported physical activity among individuals with SCI is due to activities of daily living. The amount of physical activity was not related to lesion level, age, body mass index or waistline size. Greater heavy-intensity activity was related to lower levels of pain and fatigue and higher levels of self-efficacy, whereas higher amounts of mild-intensity activity and total activity were related to less depressive symptoms.

CONCLUSIONS

Activities of daily living are a large component for physical activity among individuals with SCI. It appears that greater physical activity is associated with less secondary complications (pain, fatigue and depression) in individuals with SCI.

Protein markers in the microcyst of the posteroventral cochlear nucleus of the gerbil

Microcysts are most evident in the posteroventral and anteroventral cochlear nuclei (PVCN and AVCN) of the Mongolian gerbil. The origin and contents of the microcyst are not elucidated at present. The present study investigated the possible inclusions in the microcyst by employing immunocytochemical labeling to localize the existence of various protein markers. Thirty and 100 microm thick sections were used to substitute and reconstruct between 6 and 20 paraffin serial sections, respectively. In 30-microm-thick slice sections, immunoreactivity of glial fibrillary acidic protein (GFAP-IR), mitochondria inner membrane (MCA-In-IR), S-100 (S-100-IR), serotonin (5-HT-IR), myelin proteolipid protein (PLP-IR) and substance P (SP-IR) abutted on the perimeter of the microcyst. The immunolabeled SP-positive cells were adjacent to the evagination of the microcyst. In 100-microm-thick slice sections, immunoreactivity of nitric oxide synthase (NOS-IR) and somatostatin (SOM-IR) mainly precipitated as flocculent structures in the small to medium-sized microcysts. 5-HT-IR also precipitated as an elongated flocculent stalk adjacent to the large microcyst or randomly distributed in the neuropil. The findings suggest that GFAP, MCA-In, S-100, 5-HT, PLP, SP, NOS and SOM may be involved in modulating the physiological functions and maintaining micro-environmental homeostasis of the microcyst in the cochlear nucleus of the gerbil.

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.

Post-poliomyelitis syndrome: case report and review of the literature

INTRODUCTION

Postpoliomyelitis syndrome (PPS) refers to the new neuromuscular symptoms that occur in patients years after their acute poliomyelitis has stabilised. PPS cases seen now are probably related to the poliomyelitis epidemics of the 1940s and 1950s.

CLINICAL PICTURE AND INVESTIGATION

A 57-year-old Chinese man with a history of poliomyelitis affecting both lower limbs presented with left upper limb weakness. Physical examination revealed atrophy of his left upper limb muscles. There were fasciculations in the biceps and brachioradialis muscles. Electromyography revealed ongoing denervation neurogenic units in the C5 to TI myotomes comparable with PPS.

CONCLUSION

The aim of this paper is to review the present situation and to give a short summary of PPS, which can be difficult to diagnose because the symptoms of presentation are usually non-specific. We describe a case of PPS and review the current literature.

Mortality after proximal hip fracture in the Singapore population

The aims were to prospectively assess the mortality risk following proximal hip fractures, identify factors predictive of increased mortality and to investigate the time trends in mortality with comparison to previous studies. Prospectively collected data from 68 consecutive patients who had been admitted to a regional hospital from May 2001 to September 2001 were reviewed. The mean age of the patients was 79.3 years old (range, 55-98) and 72.1% females. Patients were followed prospectively to determine the mortality risk associated with hip fracture over a two-year follow-up period. The acute in-hospital mortality rate at six months, one year and two years was 5.9% (4/68), 14.7% (10/68), 20.6% (14/68) and 25% (17/68) respectively. One-year and two-year mortality for those patients who were 80 or older was significantly higher than for other patients and the number of co-morbid illnesses also had significant effect. Cox regression was performed to determine the significant predictors for survival time. It was noted that patients 80 years or older were at higher risk of death compared with those less than 80 years as well as those with higher number of co-morbid illnesses. Our mortality rates have not declined in the past 10 years when compared with previous local studies. We conclude that for this group of patients studied, their mortality at one year and two years could be predicted by their age group and their number of co-morbid illnesses. (Hip International 2005; 15: 166-70).

Field-induced structures in miscible ferrofluid suspensions with and without latex spheres

We explore magnetic-field-induced ordering and microphase separation of aqueous ferrofluid and of aqueous mixtures of ferrofluid with nonmagnetic latex spheres. The ferrofluid is a surfactant stabilized aqueous suspension of magnetite (Fe3O4) particles with average diameter 20 nm (including the approximately 2.5-nm thick surfactant layer); the nonmagnetic latex spheres are charge stabilized polymethylmethacrylate (PMMA) particles with diameters of 42 nm, 108 nm, and 220 nm. In the presence of a uniform magnetic field, needlelike ferrofluid droplets formed that eventually grew to sample-traversing columns at fields of approximately 600 G; the two-dimensional structure of these columns was, however, glassy rather than hexagonal. In higher fields, approximately 1000 G, the columns stretched and coalesced into sheetlike striped liquids, but a true lamellar phase was not observed. The addition of nonmagnetic latex spheres to the ferrofluid suspension lowered substantially the critical field for the formation of columns, and induced lamellar (stripe) phases at relatively low applied fields. Image analysis was used to determine the spatial correlation functions, the average needle or column spacing, and the average lamellae spacing of these samples as a function of latex sphere size and concentration.

Aberrant caspase-activated DNase (CAD) transcripts in human hepatoma cells

The gene of caspase-activated DNase (CAD), the key enzyme for nucleosome cleavage during apoptosis, is mapped at chromosome 1p36, a region usually associated with hemizygous deletions in human cancers, particularly in hepatoma (HCC). It is tempting to speculate that CAD plays a tumour-suppressive role in hepatocarcinogenesis. To address this, we examined the CAD transcripts in six human HCC cell lines, one liver tissue from a non-HCC subject, and peripheral blood leukocytes (PBL) from three healthy individuals. Alternatively spliced CAD transcripts with fusion of exon 1 to exon 7 were isolated in most of the examined samples including HCC cells and normal controls. However, relatively abundant alternatively spliced CAD transcripts with fusion of exon 2 to exon 6 or 7, in which the corresponding domain directing CAD interaction with ICAD was preserved, were found only in poorly differentiated Mahlavu and SK-Hep1 cells. Interestingly, an abnormal CAD transcript with its exon 3 replaced by a truncated transposable Alu repeat was isolated in Hep3B cells, indicative of the implication of an Alu-mediated genomic mutation. Moreover, mis-sense mutations in the CAD genes were identified in all six HCC cell lines. Upon UV-induced apoptosis, DNA fragmentation efficiency was found to be intact, partially reduced and remarkably reduced in Huh7 and J328, Hep3B and HepG2, and Mahlavu cells, respectively. That mutations and aberrantly spliced transcripts for the CAD gene are frequently present in human HCC cells, especially in poorly differentiated HCC cells, suggests a significant role of CAD in human hepatocarcinogenesis.

Decommissioning of a 60Co unit and estimation of personal doses

Chang-hua Christian Hospital needs to uninstall the 60Co unit. The mode of this 60Co teletherapy unit is SHIMADZU RTGS-10. The original lead head was taken as the source container of this 60Co unit. The source head was dismantled and put into the prepared wooden box, after the source was sealed. This study describes the planning and dismantling of the retirement and transport of the 60Co unit, and personal doses measured during the procedure. This work estimates the doses of radiation received by exposed workers during the dismantling of the machine. The workers received doses of approximately 53 microSv. This study shows that the original lead head can be used as the source container of this 60Co unit. The 60Co machine was smoothly dismantled and transported by conscientious and careful workers, using planned and controlled radiation protection, following the ALARA (as low as reasonably achievable) rule.

Compression forces and amount of outer coating layer affecting the time-controlled disintegration of the compression-coated tablets prepared by direct compression with micronized ethylcellulose

The influence of compression force to inner core tablet or to outer coating layer of the compression-coated tablet on the function of time-controlled disintegration was investigated. The inner core tablet was directly compacted by sodium diclofenac (model drug) and ethylcellulose (EC) with 4.6-microm particle size was used as an outer coating layer. The immersion time of the compression-coated tablet previously soaked in pH 1.2 solution to simulate the residence time of the tablet in the GI tract affecting the dissolution behavior of the compression-coated tablet was also investigated. The effect of the amount of the outer coating layer used on the drug release was examined. The results indicate that sodium diclofenac released from these compression-coated tablets exhibited a longer lag of a period about 16.3 h in both distilled water and pH 6.8 buffer solution, followed by a different drug release behavior. The lag time was independent of the pH of dissolution medium, and the immersion time in pH 1.2 solution. After that lag time, the outer shell of the compression-coated tablets broke into two halves to make a rapid drug release. However, the drug release behavior of the soaked tablet in pH 6.8 buffer solution was dependent on the immersion time. The compression force < 200 kg/cm(2) to the inner core tablet influenced the release behavior of drug less, but > 200 kg/cm(2) might delay the lag time. The lag time of the compression-coated tablets was linearly correlated with the compression force to the outer coating layer (r = 0.9896). We also found that the more the amount of outer coating layer added, the longer the lag time obtained. The study demonstrates that the time-controlled disintegration of the compression-coated tablet was effectively controlled by the compression force applied and the amount of outer coating layer added.

Ruptured cystic teratoma of the testis in a neonate

Neonatal testicular tumors are extremely rare. We report the case of a full-term male newborn with right hemiscrotal swelling found immediately after birth. The right hemiscrotal skin gradually turned dusky dark and then adhered to the hard scrotal contents. Missed right testicular torsion was suspected and emergency exploration was not attempted. Right hemiscrotal swelling became aggravated, so right orchiectomy and left orchidopexy were performed. During surgery, severe inflammation of the right testis and the right hemiscrotum were observed and diffuse hemorrhage with focal hematomas was noted within the removed right testis. Histopathology of the specimen revealed a ruptured mature cystic teratoma of the testis. The alpha-fetoprotein concentration was 729 x 10(4) micrograms/L 10 days after the operation, and dropped to 185 x 10(4), 25 x 10(4), and less than 20 x 10(4) micrograms/L 2, 5, and 8 months later, respectively. Postoperative abdominal and pelvic computerized tomography scans revealed neither lymphadenopathy nor distant metastasis. During a follow-up of 8 months, no evidence of tumor recurrence was found. Although extremely rare, testicular tumors should be included in the differential diagnosis of an enlarged hard or firm scrotal mass in the male neonate.

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.

Screw-in atrial lead in a sick sinus syndrome patient with anomalous inferior vena cava

Anomalous inferior vena cava without intracardiac anomaly is an unusual condition. Herein, we report a 48-year-old female with left-sided inferior vena cava and azygous continuation. accompanied by sick sinus syndrome. This anomaly resulted in difficulty in implanting a traditional hook-on atrial lead. Atrial lead dislodgment occurred repeatedly soon after implanting the pacemaker because of an anomalous zygous vein draining into the superior vena cava, making a giant connection with the right atrium, thus eliminating the space of the atrial appendage for lead lodgment. Finally, we attempted to utilize a screw-in atrial lead in this patient and she is currently doing well. We therefore suggest that a screw-in atrial lead should be taken into account for such patients in order to obtain a stable fixation.

Genetic analysis of recent Taiwanese isolates of a variant of coxsackievirus A24

Epidemics of acute hemorrhagic conjunctivitis (AHC) caused by a variant of coxsackievirus A24 (CA24v) reappeared in Taiwan in 1990 and 1994, following the first two epidemics of 1985--86 and 1988--89. To analyze the genetic diversity of recent CA24v in Taiwan, 7 Taiwanese strains isolated during the 1990--94 period were studied together with one Japanese and two Thai strains isolated in 1993. A fragment of 674 nucleotides between the carboxy terminal 3A and the amino terminal 3D polymerase, including the entire 3C protease (3C(pro)), was amplified by a reverse transcription-polymerase chain reaction (RT-PCR) and the nucleotide sequences were determined. In the 549 nucleotides (183 amino acids) of the entire 3C(pro), we found nucleotide differences at 80 positions between 10 strains and the prototype strain, EH24/70, one of the earliest strains of CA24v. Most of the nucleotide changes were synonymous substitutions and only nine amino acid changes were found. The nucleotide sequence homologies among 71 strains worldwide were 88-100%. These 71 nucleotide sequences were then analyzed by Neighbor-joining method and phylogenetically separated into three distinct genotypes. Genotype I consisted of early strains isolated in 1970--71 from Singapore and Hong Kong. Genotype II included isolates from Singapore and Thailand obtained in 1975. Genotype III comprised strains from the eastern hemisphere isolated in 1985--94 from Japan, Taiwan, China, Hong Kong, Thailand, Singapore, Pakistan and Ghana. They were further divided chronologically into six clusters. The recent isolates from Taiwan obtained in 1985/1986, 1988/1989 and 1990--94 were classified into genotype III Clusters 1, 5, and 6 respectively. The evolutionary rate was re-estimated to be 3 x 10(- 3) 30 years after the emergence of the virus.

Molecular epidemiology of enterovirus 71 in Taiwan

Taiwan suffered a severe and widespread outbreak of enterovirus infection in 1998. More than 400 children were hospitalized, with seventy-eight fatalities due to central nerve system (CNS) involvement and cardiopulmonary collapse. Enterovirus 71 (EV71) was incriminated as the causative agent for the fatal cases. To understand the viral molecular epidemiology in this outbreak, fragments of 207-bp length of the VP4 region in 23 Taiwanese EV 71 isolates were sequenced. Pair-wise comparison revealed a 17.5-24.4% difference between the isolates and the prototype BrCr. However, all the changes in the VP4 region of the isolated strains were synonymous substitutions. Phylogenetic analysis was performed on these 23 isolates and 21 others deposited in GenBank. In this study, forty-four EV71 isolates from the world were separated into three distinct genotypes: A, B and C. The EV71 prototype strain, BrCr/70, is the only strain of genotype A. Group B included strains from the United States, Japan and Taiwan. Most strains in genotype B were isolated prior to 1990. Group C consisted of strains from Japan and Taiwan. Most strains of genotype C were isolated after 1990, they were further divided into 3 clusters: i.e. C-1, C-2 and C-3. In Taiwan, two genotypes, B and C-3, were co-circulating during the outbreak in 1998, although a minor group of genotype B may have appeared in Taiwan before 1986. The majority of the isolates clustered in genotype C-3. Genotype C showed a higher evolutionary rate than genotype B (3.9 x 10(-3) vs. 1.4 x 10(-3)) in the VP4 region. There seems to be a worldwide trend with strains of genotype B appearing earlier than strains of genotype C which took over later in the dominance.

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.

Hemorrhagic viral keratoconjunctivitis in Taiwan caused by adenovirus types 19 and 37: applicability of polymerase chain reaction-restriction fragment length polymorphism in detecting adenovirus genotypes

PURPOSE

Acute keratoconjunctivitis with prominent subconjunctival hemorrhage (SCH) is usually perceived by a clinician as acute hemorrhagic conjunctivitis (AHC) associated with enteroviruses; however, SCH can also be an adenoviruses infection. A rapid and sensitive laboratory diagnosis is helpful for differential diagnosis. Therefore, the sensitivity and applicability of polymerase chain reaction (PCR) and reverse transcription (RT)-PCR diagnoses were evaluated for keratoconjunctivitis associated with viral infection.

METHODS

Conjunctival swabs from patients with acute conjunctivitis were tested using a PCR-restriction fragment length polymorphism (PCR-RFLP) for adenovirus detection and RT-PCR for enterovirus detection. The results were compared with those using the culture isolation and neutralization test; also, the clinical findings of the patients were analyzed with special attention to SCH patterns.

RESULTS

Neither coxsackievirus A type 24 variant (CA24v) nor enterovirus type 70 (EV70) was detected in 113 patients with acute conjunctivitis. The positive results of adenovirus (Ad) were 39.9% by the PCR method and 37.1% by culture isolation. For the patients with adenoviral conjunctivitis, 68.1% was owing to Ad37 and 19.2% was owing to Ad19. SCH was present in 51.5% of the positive cases, and 44.7% of the Ad-positive patients had secondary illnesses.

CONCLUSIONS

SCH can be a predominant presentation of Ad19 and Ad37 keratoconjunctivitis and may herald a new stage in the evolution of adenoviruses. PCR and PCR-RFLP are rapid and reliable methods for Ad detection and typing; however, if the amplified genes and restriction enzymes are not properly selected, they may not be able to detect new genotypes of adenoviruses or the evolution of these viruses.

[Illness knowledge, social support and self care behavior in adolescents with beta-thalassemia major]

The purpose of this study was to explore the relationships among illness knowledge, social support and self-care behavior in adolescents with beta-thalassemia major. The subjects were 58 beta-thalassemia major adolescents recruited from the pediatric hematology outpatient departments of three hospitals in North Taiwan. All data were analyzed by descriptive statistics, one-way ANOVA, t-test, Pearson correlation, and stepwise multiple regression. The results showed that: (1) Scoring in illness knowledge, the best was treatment knowledge, and the worst was the knowledge of complications and symptoms. (2) The result for social support indicated that the family was the major source of support, and that classmates/friends provided the least support for thalassemic adolescents. (3) Scoring in self care behavior, the best was the medical and chelate therapy, and the worst was the management of problems and coping. (4) Individual characteristic differences, including sex, level of education, length of illness, complications of thalassemia, hospitalization due to thalassemic complications and receiving other treatments were correlated with their illness knowledge, social support or self-care behavior. (5) Illness knowledge, social support which were positively correlated with self-care behavior. (6) 50.0% of the variance in self-care behavior can be explained by emotional support from family, general knowledge of thalassemia, treatment knowledge and appraisal support from family. These findings could provide referential material for nursing research and nursing practice.

Emerging new frontiers in cardiac pacing: cardiac pacing in heart failure

Indications for pacing have leapt beyond sinus node dysfunction and atrioventricular (AV) block. Pacing for the purpose of improving hemodynamics has become the prime subject of exploration. Several studies have reported hemodynamic and clinical improvement with bi-ventricular pacing and AV sequential pacing. Data is still pouring in from the various ongoing trials regarding the beneficial effects of these methods of pacing. This is especially true in a subset of patients with intractable heart failure. There are several indicators to identify these patients. Those who have intra-ventricular conduction defects and those who demonstrate hemodynamic improvement after temporary pacing are certainly the candidates who will benefit most from this new form of pacing. Prolonged PR interval or left bundle branch block with intractable heart failure also falls into this category. The rationale of pacing in heart failure is to correct the cardiac dysynchrony that occurs frequently in these patients. Cardiac dysynchrony can occur due to ineffective synchronization between atria and ventricles (AV dysynchrony) or due to lack of synchronization within the two ventricles (ventricular dysynchrony). This is overcome by AV sequential pacing or by multi chamber pacing using the coronary sinus as portal of entry of the electrode into the cardiac vein to pace the left ventricle. Pacing leads and generators have been designed to suit the new found methods of pacing. Clinical trials are in full swing to establish the efficacy of these methods.

Efficient diagnosis of dengue infections using patients' peripheral blood leukocytes and serum/plasma

OBJECTIVE

Dengue fever has been one of the most important health problems in Taiwan since a large outbreak during 1987 and 1988. It is critically necessary to have a diagnostic approach that can detect early infections in an outbreak or even find infections existing in silent transmission of the disease.

METHODS

To develop an efficient diagnostic protocol, 105 plasma/serum and 35 peripheral blood leukocyte (PBL) specimens from the 1994 outbreak in southern Taiwan were collected for assessment by various diagnostic techniques in this study.

RESULTS

In acute blood samples, dengue viruses were isolated from 19.4% (14/72) and 33.3% (14/42) of reported and confirmed cases, respectively. Viral RNA in serum/plasma was detected from 20.0% (12/60) of acute samples, which was significantly higher than that from convalescent samples (3/44; 6.8%). However, viral RNA in PBLs, detected by reverse transcription polymerase chain reaction (PBL-RT-PCR), could be observed in 73.2% (19/26) and 66.7% (6/9) of acute and convalescent samples, respectively. The persistence of dengue viruses in PBLs was also evidenced by the presence of viral antigens in 42.9% (4/7) of confirmed convalescent samples by the immunofluorescence antibody test. In addition, IgM antibodies were detected in 43.8% (46/105) of reported cases and 85.2% (46/54) of confirmed cases by the IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA).

CONCLUSIONS

Although IgM antibody detection achieved the highest detection rate among techniques assessed in this study, no individual test can actually reach full efficiency for early diagnosis of dengue infections. Here, we propose a protocol which applies MAC-ELISA and PBL-RT-PCR in sequence, by which 22 confirmed cases were definitely proved as dengue positive. High levels of both sensitivity and specificity were shown in this protocol.

Isolation of rat mitochondrial transcription factor A (r-Tfam) cDNA

We have isolated rat mitochondrial transcription factor A (Tfam; formerly known as mtTFA) cDNA clones from a rat cerebellum cDNA library using human Tfam cDNA as a probe. The deduced amino acid sequence of r-Tfam shows 62% and 89% overall identity to human and mouse Tfam, respectively. We also show the presence of two r-Tfam isoforms in testis as for mouse. Our findings suggest that the mechanisms underlying transcription of mitochondrial genes are conserved among rat, mouse, and human.

Micronized ethylcellulose used for designing a directly compressed time-controlled disintegration tablet

Ethylcellulose (EC) of varying particle sizes has been used as an outer coating layer to design a novel dry-coated tablet with time-controlled drug release. This dry-coated tablet, containing a core tablet of sodium diclofenac and an outer coating layer of EC, was prepared by direct compression. The drug release from dry-coated tablet exhibited an initial lag period that was dependent on the particle size of the EC powder, followed by a stage of rapid drug release. The smaller the EC particle size used the longer the lag time obtained, suggesting the particle size of EC powder could modulate the timing of drug release from such a dry-coated tablet. The period of the lag time for sodium diclofenac released from dry-coated tablets was correlated with the penetration distance of the solvent into dry-coated tablet by an in vitro dye penetration study. The densest packing of EC powders appeared on the upper and lower surfaces of dry-coated tablet after compression, resulting in a tight structure yielding a slower penetration of the solvent. Whereas loose packing of EC powders occurred in the middle of the lateral surface of dry-coated tablet, this loosely packed surface readily allowed solvent penetration and that finally caused the splitting of tablet shell into two halves in the dissolution medium. The results suggest that these dry-coated tablets prepared with different particle sizes of EC powder as an outer coating layer might offer a desirable release profile for drug delivery at the predetermined times and/or sites.

The effects of aging on AV nodal recovery properties

The purpose of this study was to assess the changes of AV nodal recovery properties with aging. Although in children and young adults it was found that there were age dependent changes in their AV nodal recovery properties, in the older population this information was not available. In 92 subjects (aged 16-92 years) without AV nodal disease or dual AV nodal pathway physiology, their AV nodal recovery curves were studied by delivering premature atrial extrastimuli coupled to basic atrial beats during cardiac electrophysiological study. Data were analyzed using linear regression and curve-fitting techniques. Patients were grouped by age, group I < 40 years (n = 33), group II 40-59 years (n = 26), and group III > 60 years (n = 33). The results showed that the AV nodal recovery curve did not change significantly in the aging process except that the AV nodal effective refractory period had a positive correlation with increasing age. The latter was significantly increased in group III when compared to group I or group II. For this parameter, when patients whose AV nodal refractory period was limited by the atrial refractory period were excluded, there was still a statistically significant increase in group III compared to group II (P < 0.05): group I (n = 27): 202+/-42 ms; group II (n = 17): 197+/-26 ms; and group III (n = 17): 224+/-46 ms. The results suggest that the AV nodal recovery curve remains unchanged once it reaches adulthood, with the exception that the nodal effective refractory period becomes slightly longer after age 60.

Low prevalence of coronary arterial disease in Chinese adults with mitral stenosis

BACKGROUND

We attempted to evaluate the prevalence of coronary artery disease in Chinese adults with severe rheumatic mitral stenosis.

METHODS

We prospectively performed coronary angiography in 119 consecutive Chinese patients older than 40 years old (mitral valve area less than 1.5 cm2) who were about to undergo balloon mitral commissurotomy for significant rheumatic mitral stenosis. The exclusion criteria were the presence of left atrial cavitary thrombi or mitral regurgitation greater than grade 3.

RESULTS

There were 32 men (26%) and 87 women (74%) with a mean age of 55 +/- 9.7 years (ranging from 40 to 78). Ninety-two patients (77%) were in atrial fibrillation. The prevalence of risk factors for atherosclerotic cardiovascular disease were hypertension (22%), diabetes mellitus (4%), hypercholesterolemia > or = 240 mg/dL (5%), hypertriglyceridemia > or = 150 mg/dL (13%), and cigarette use (7%). Coronary artery disease on angiography was defined as stenosis of more than 50% of the luminal diameter. We found that only 2 patients (1.7%) had coronary artery disease.

CONCLUSION

The prevalence of coronary artery disease was much lower than in previous reports, some of which, however, had already pointed out the relatively low prevalence of coronary artery disease in rheumatic mitral disease. The definite mechanisms require further study.

The characteristics of phosphorus removal in an anaerobic/aerobic sequential batch biofilter reactor

Previous research has shown that alternated anaerobic/aerobic conditions are effective in removing phosphorus from wastewater using a biofilter system. However, few studies have been conducted on the features of polyphosphate (poly-P) accumulating organisms (PAOs) in biofilm on phosphorus removal. This study investigated the characteristics of the phosphorus removal mechanism in various hydraulic loads and anaerobic/aerobic time ratios using a sequential batch biofilter reactor. The storage and release of intracellular inclusions, especially polyhydroxyalkanoates (PHAs) and poly-P, would be an important factor for phosphorus removal. Under different operating conditions, total phosphorus removal was always determined by accumulation of PHAs and phosphorus release under the anaerobic phase. The PHA accumulation under the anaerobic phase was always in proportion to the biofilm phosphorus content under aerobic conditions. The result shows PAOs activity was closely related to PHA accumulation. However, the PHA accumulation under the anaerobic phase would be dependent on the hydrolysis of the complex carbon source into short chain fatty acids (SCFA). The result would be demonstrated by the simple carbon source effect. The effect of the An/Ox time ratio on TP removal was significant. Shorter anaerobic time would result in insufficient phosphorus release and greater time would result in inactive PAOs. The appropriate An/Ox time ratio was suggested as 1/2. Comparisons of the phosphorus removal characteristics between biofilm and suspended growth under the same growth conditions are discussed in detail.

Localizing ventricular tachycardia through entrainment

Area(s) of slow conduction are thought to be present within the reentry circuit of most clinically important ventricular tachycardia (VT). To prevent recurrence after ablation of VT late after myocardial infarction, it is desirable to localize and destroy area(s) of slow conduction "critical link" within the reentry circuit. Conventionally, they may be identified by endocardial catheter mapping, continuous electrical activity, mid-diastolic potentials, earliest endocardial activation, pace-mapping etc. However, none of these methods are very specific. Entrainment method may be used to localize the slow conduction zone of reentrant VT. Concealed entrainment is consistent with pacing at a site in the reentry circuit but may also occur at some "bystander" sites that are close to the reentry circuit but are not participating in the circuit itself. During pacing at the slow conduction area of the reentry circuit, the stimulus to QRS (S-QRS) interval should equal the electrogram to QRS (EG-QRS) interval during VT. Similarly the post-pacing interval (PPI) approximates the tachycardia cycle length. During pacing at bystander sites, the S-QRS interval may be greater, less than or equal to the EG-QRS interval, depending on the conduction time from the bystander site to the circuit. The PPI, however, always exceed the tachycardia cycle length. In conjunction with concealed entrainment, the use of diastolic potential, double potentials and continuous electrical activity enhances the prediction of radiofrequency termination of post-infarction VT.

Brugada syndrome without mutation of the cardiac sodium channel gene in a Taiwanese patient

We describe a 45-year-old Taiwanese man with specific features of Brugada syndrome but no clinical features of structural heart disease. He was successfully treated with an implantable cardioverter-defibrillator. His electrocardiogram (ECG) patterns changed intermittently. Alpha-adrenoceptor stimulation and beta-adrenoceptor blockade augmented the characteristic ST-segment elevation, whereas alpha-adrenoceptor blockade and beta-adrenoceptor stimulation mitigated the ST-segment elevation. Intravenous procainamide administration did not aggravate ST-segment elevation when ECG had shown coved ST elevation in the right precordial leads. Molecular study did not reveal the same mutations in the cardiac sodium channel gene (SCN5A) as previously reported in Brugada syndrome. This case demonstrates the genetic heterogeneity of SCN5A in Brugada syndrome.

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.

Staurosporine promotion of formation of continuous monolayers of primary rat hepatocytes by improving attachment and spreading

Primary rat hepatocytes form discontinuous monolayers even at their maximum density. Here, we show that staurosporine promotes attachment and spreading of hepatocytes onto culture substrates, so that hepatocytes form a close, continuous monolayer. This treatment did not attenuate major hepatic functions. Therefore, this technique is promising for making seamless cell-sheet structures, which will be applicable for cell-polarity experiments or artificial liver construction.

An outbreak of enterovirus 71 infection in Taiwan, 1998. II. Laboratory diagnosis and genetic analysis

BACKGROUND

An epidemic of enterovirus 71 (EV71) occurred in Taiwan from April to December of 1998, with two peaks, one in June and the other in October. Many enteroviruses were isolated in our laboratory from 258 cases during this outbreak. Approximately half of the enteroviruses isolated were EV71 and one fifth were coxsackievirus A16.

OBJECTIVES

To analyze laboratory findings in the EV71 epidemic of 1998 in Taiwan, various EV71 specimens in different cell lines were examined. In addition, genetic analysis of 5' non-coding region (NCR) was performed to analyze the strain variation in this outbreak.

RESULTS

The cytopathic effect induced by EV71 was observed 2-13 (mean of 4.5) days post-inoculation in Vero cells and 4-15 (mean of 6.6) days in green monkey kidney (GMK) cells inoculated with throat swabs. Of the total positive EV71 cases, virus was most frequently obtained from throat swabs (91.7%), less from stools (64.8%), and none from cerebral spinal fluid (CSF). Molecular analyses of EV71 by sequencing the 5' NCR of 34 strains obtained from different clinical categories and various geographic areas showed that their sequences differed (0-13 bp in 681 bp sequenced) by approximately 0-2%. The sequences of these isolates differed from EV71 prototype BrCr or MS strain by 17.5-19%, with the exception of two samples which exhibited nucleotide variation by only 8.9 and 8.2%, when compared to the MS strain.

CONCLUSION

EV71 was most frequently isolated from throat swab specimens in Vero cells. The molecular analyses of the 5' NCR of EV71 revealed that most isolates from this epidemic belonged to a group of closely related clones and only two were in a different group which was clustered with the EV71 MS strain.

Genetic analysis of enterovirus 71 isolated from fatal and non-fatal cases of hand, foot and mouth disease during an epidemic in Taiwan, 1998

A large scale outbreak of hand-foot-and-mouth disease (HFMD) occurred in Taiwan in 1998, in which more than 80 children died of shock syndrome with pulmonary edema/hemorrhage. Enterovirus 71 was implicated as the cause of this outbreak. In order to understand the virological basis responsible for mortality on this scale, nucleotide sequences of VP1 that is important for serotypic specificity, and the 5'-non-coding region (5'-NCR) that is important for replication efficiency, were analyzed comparatively. Phylogenetic analysis of both VP1 and 5'-NCR of nine EV71 isolates derived from specimens of fatal patients and seven isolates derived from uncomplicated HFMD patients showed that all but one isolate fell into genotype B. The one distinct isolate from a case of uncomplicated HFMD belonged to genotype C that was clustered along with one isolate from Taiwan in 1986. Complete sequence analysis of two selected isolates, one from the spinal cord of a fatal case and one from the vesicle fluid of a patient with mild HFMD, confirmed a high degree (97-100%) of identity in nucleotide sequence throughout the entire genome, except focal regions of 3C and 3'-NCR where the nucleotide homology was 90-91%. The identity of the deduced amino acid sequence in the 3C region that encodes viral proteinase dropped further to 86%, a result of missense mutations at the first nucleotide position of many codons.

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.

Negative regulation of the antimetastatic gene Nm23-H1 by thyroid hormone receptors

Metastasis of various malignant cells is inversely related to the abundance of the Nm23-H1 protein. The possible role of thyroid hormones in tumor metastasis has now been investigated by examining the effect of T3 on the expression of the Nm23-H1 gene. Human hepatoma HepG2 cells, in which endogenous thyroid hormone receptor subtype alpha1 (TRalpha1) is expressed at a low level, were stably transfected, either with expression plasmids encoding wild-type TRalpha1 or a dominant negative mutant of TRalpha1, or with the empty vector (yielding HepG2-Wt, HepG2-Mt, and HepG2-Neo cells, respectively). Immunoblot analysis revealed that exposure of HepG2-Wt and HepG2-Neo cells, but not HepG2-Mt cells, to T3-induced time-dependent decreases in the abundance of Nm23-H1 messenger RNA and protein, with the extent of these effects correlating with the level of expression of TRalpha1. An in vitro assay also revealed that T3 induced a marked increase in the invasive activity of HepG2-Wt cells; it induced a smaller increase in that of HepG2-Neo cells but had no effect on that of HepG2-Mt cells. Finally, the promoter region of Nm23-H1 spanning nucleotides -471 to -437 (relative to the transcriptional initiation site) inhibited the expression of a downstream reporter gene, in a T3-dependent manner, in COS-1 cells also transfected with an expression plasmid encoding TRalpha1 or TRbeta1. The DNA binding domain of TRbeta1 was required for this inhibitory effect. These results indicate that T3, acting through TRs, inhibits transcription of Nm23-H1, and that this effect is mediated by a negative regulatory element in the promoter region of the gene. Thus, it is possible that T3 promotes tumor metastasis by inducing down-regulation of Nm23-H1 expression.

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.

Nephrotic syndrome in a bone marrow transplant recipient without chronic graft-versus-host disease

A 5-year-old girl developed severe proteinuria and microscopic hematuria 17 months after allogeneic bone marrow transplantation (BMT) for chronic myeloid leukemia. These nephrotic symptoms occurred during cyclosporin tapering, in the absence of other signs of chronic graft-versus-host disease (GVHD). A renal biopsy revealed focal segmental glomerulosclerosis. After methylprednisolone therapy, the proteinuria gradually decreased. The altered or disordered immune regulation that occurred after BMT may have resulted in the development of nephrotic syndrome.