Preemptive Living Donor Kidney Transplantation and Kidney Function at the Initial Hospital Visit: A Single-Center Case-Control Study.

BACKGROUND: Studies have revealed that patients who undergo preemptive kidney transplantation (PKT) have favorable prognoses compared with those who undergo kidney transplantation after the initiation of dialysis. The number of PKT cases performed worldwide has been increasing. The goal of this study was to determine the clinical characteristics of patients who may successfully receive PKT. METHODS: A single-center, case-control study was conducted to determine the clinical factors that lead to referral for PKT. RESULTS: Between April 1, 2009, and August 1, 2015, a total of 118 patients underwent living donor kidney transplantation. Thirty of these patients had not undergone dialysis before their initial visit to the study hospital. Of these, 20 received kidney transplantation before and after dialysis initiation, respectively (group PKT+, successful PKT; group PKT-, failed PKT). The baseline characteristics at the primary visit were compared between groups. The median duration from the first visit to the study institution to PKT was 5.6 ± 0.7 months. Serum creatinine (Cr) levels differed significantly between groups (PKT+ vs PKT-, 6.0 ± 0.3 mg/dL vs 7.5 ± 0.5 mg/dL; P = .03). The receiver-operating characteristic curves revealed that a serum Cr level >5.7 mg/dL at the initial visit to the unit was a cutoff point for predicting the success of PKT (area under the curve, 0.721; P = .02). CONCLUSIONS: Our results indicate that PKT should be performed within ∼6 months of the initial visit to the transplant center. Serum Cr levels <5.7 mg/dL predict successful PKT.

Characteristic patterns of relapse after allogeneic hematopoietic SCT for adult T-cell leukemia-lymphoma: a comparative study of recurrent lesions after transplantation and chemotherapy by the Nagasaki Transplant Group.

Allogeneic hematopoietic SCT (allo-SCT) is a promising therapy that may provide long-term durable remission for adult T-cell leukemia-lymphoma (ATL) patients; however, the incidence of relapse associated with ATL remains high. To determine the clinical features of these patients at relapse, we retrospectively analyzed tumor lesions in 30 or 49 patients who relapsed following allo-SCT or chemotherapy (CHT), respectively, at three institutions in Nagasaki prefecture between 1997 and 2011. A multivariate analysis revealed that the development of abnormal lymphocytes in the peripheral blood of patients at relapse was less frequent after allo-SCT than after CHT (P<0.001). Furthermore, relapse with a new lesion only in the absence of the primary lesion was more frequent in allo-SCT (P=0.014). Lesions were more frequently observed in the central nervous systems of patients who relapsed with new lesions only (P=0.005). Thus, the clinical manifestation of relapsed ATL was slightly complex, especially in post-transplant patients. Our results emphasized the need to develop adoptive modalities for early and accurate diagnoses of relapsed ATL.

Expression of myeloperoxidase in acute myeloid leukemia blasts mirrors the distinct DNA methylation pattern involving the downregulation of DNA methyltransferase DNMT3B.

Myeloperoxidase (MPO) has been associated with both a myeloid lineage commitment and favorable prognosis in patients with acute myeloid leukemia (AML). DNA methyltransferase inhibitors (decitabine and zeburaline) induced MPO gene promoter demethylation and MPO gene transcription in AML cells with low MPO activity. Therefore, MPO gene transcription was directly and indirectly regulated by DNA methylation. A DNA methylation microarray subsequently revealed a distinct methylation pattern in 33 genes, including DNA methyltransferase 3 beta (DNMT3B), in CD34-positive cells obtained from AML patients with a high percentage of MPO-positive blasts. Based on the inverse relationship between the methylation status of DNMT3B and MPO, we found an inverse relationship between DNMT3B and MPO transcription levels in CD34-positive AML cells (P=0.0283). In addition, a distinct methylation pattern was observed in five genes related to myeloid differentiation or therapeutic sensitivity in CD34-positive cells from AML patients with a high percentage of MPO-positive blasts. Taken together, the results of the present study indicate that MPO may serve as an informative marker for identifying a distinct and crucial DNA methylation profile in CD34-positive AML cells.

Autocrine and/or paracrine growth of aggressive ATLL cells caused by HGF and c-Met.

Adult T-cell leukemia/lymphoma (ATLL) is a neoplasia characterized by the massive invasion of various organs by tumor cells. Previously, we found that expression of the gene for c-Met, a receptor tyrosine kinase for hepatocyte growth factor (HGF), was specific to the acute type among 41 patients with ATLL by microarray. First in the present study, we analyzed the survival of the patients in relation to expression of c-Met and HGF in ATLL cells. Expression of the former but not the latter was associated with poor prognosis. Then, we analyzed the growth of ATLL cells caused by HGF and c-Met. c-Met was expressed in 0/7 chronic ATLLs, 12/14 acute ATLLs, 1/1 IL-2-independent ATLL cell line and 1/7 IL-2-dependent ATLL cell lines as assessed by flow cytometry. HGF induced the proliferation of primary cells from most acute cases examined as well as the c-Met-positive KK1 cell line in contrast to c-Met-negative cells. HGF induced autophosphorylation of c-Met in c-Met-positive cells from an acute case and KK1 cells. The plasma level of HGF was elevated in acute as compared to chronic cases. The levels of HGF and/or IL-6 which induces the production of HGF by stromal cells, were elevated in the supernatant of short-term cultured cells from certain patients with acute or chronic disease. Finally, infiltrated ATLL cells and adjacent stromal cells in liver were shown to be positive for c-Met/HGF and HGF, respectively, in acute cases. Autocrine and/or paracrine growth caused by HGF and c-Met was suggested in aggressive ATLL cells secreting HGF and/or IL-6, respectively.

Expression of myeloperoxidase enhances the chemosensitivity of leukemia cells through the generation of reactive oxygen species and the nitration of protein.

Myeloperoxidase (MPO), a pivotal lineage marker for acute myeloid leukemia (AML), has been also shown to have a prognostic value: a high percentage of MPO-positive blasts correlates to favorable prognosis. To understand the relationship between the expression of MPO in leukemia cells and the response to chemotherapeutic agents, we established MPO-expressing K562 leukemia cell lines and then treated them with cytosine arabinocide (AraC). Cells expressing wild-type MPO, but not mutant MPO that could not mature, died earlier of apoptosis than control K562 cells. Reactive oxygen species (ROS) were generated more in leukemia cells expressing MPO, and the generation was abrogated by MPO inhibitors or antioxidants. Tyrosine nitration of cellular protein also increased more in MPO-expressing K562 cells than control cells after treatment with AraC. In clinical samples, CD34-positive AML cells from high-MPO cases showed a tendency to be sensitive to AraC in the colony-formation assay, and the generation of ROS and the nitration of protein were observed only when the percentage of MPO-expressing cells was high. These data suggest that MPO enhances the chemosensitivity of AML through the generation of ROS and the nitration of proteins.

Small number of HTLV-1-positive cells frequently remains during complete remission after allogeneic hematopoietic stem cell transplantation that are heterogeneous in origin among cases with adult T-cell leukemia/lymphoma.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) can provide long-term remission for patients with adult T-cell leukemia/lymphoma (ATLL) caused by human retrovirus, human T-lymphocyte virus (HTLV-1). To understand how HTLV-1-positive cells including ATLL cells were suppressed by allo-HSCT, we examined HTLV-1 provirus load and residual ATLL cells in peripheral blood of transplant recipients using PCR-based tests. We found that the copy number of HTLV-1 genome, called provirus, became very small in number after allo-HSCT; however, in most cases, provirus did not disappear even among long-term survivors. Tumor-specific PCR tests demonstrated that most of HTLV-1-positive cells that remained long after transplantation were not primary ATLL cells but donor-derived HTLV-1-positive cells. We also found a case having very low amount of residual disease in peripheral blood even long after transplantation. There was only one recipient in whom we failed to show the presence of HTLV-1 genome and antibody against HTLV-1 even with an extensive search, which strongly suggested the elimination of HTLV-1 after allo-HSCT. These results demonstrated that after allo-HSCT the small amount of residual HTLV-1-positive cells were heterogeneous in origin and that long-term disease control for ATLL could be obtained without the complete elimination of HTLV-1.

Expression and function of galectin-1 in adult neural stem cells.

Neural stem cells (NSCs) in the adult mammalian brain proliferate and continuously produce new neurons. To date, there has been little research into the functions of lectins in adult NSCs. Recently, we reported that a lectin, galectin-1, is expressed on adult NSCs and promotes their proliferation through its carbohydrate-binding ability. This evidence raises the possibility that glycans play roles in the proliferation of adult NSCs.

C-type natriuretic peptide activates a non-selective cation current in acutely isolated rat cardiac fibroblasts via natriuretic peptide C receptor-mediated signalling.

In the heart, fibroblasts play an essential role in the deposition of the extracellular matrix and they also secrete a number of hormonal factors. Although natriuretic peptides, including C-type natriuretic peptide (CNP) and brain natriuretic peptide, have antifibrotic effects on cardiac fibroblasts, the effects of CNP on fibroblast electrophysiology have not been examined. In this study, acutely isolated ventricular fibroblasts from the adult rat were used to measure the effects of CNP (2 x 10(-8) M) under whole-cell voltage-clamp conditions. CNP, as well as the natriuretic peptide C receptor (NPR-C) agonist cANF (2 x 10(-8) M), significantly increased an outwardly rectifying non-selective cation current (NSCC). This current has a reversal potential near 0 mV. Activation of this NSCC by cANF was abolished by pre-treating fibroblasts with pertussis toxin, indicating the involvement of G(i) proteins. The cANF-activated NSCC was inhibited by the compounds Gd(3+), SKF 96365 and 2-aminoethoxydiphenyl borate. Quantitative RT-PCR analysis of mRNA from rat ventricular fibroblasts revealed the expression of several transient receptor potential (TRP) channel transcripts. Additional electrophysiological analysis showed that U73122, a phospholipase C antagonist, inhibited the cANF-activated NSCC. Furthermore, the effects of CNP and cANF were mimicked by the diacylglycerol analogue 1-oleoyl-2-acetyl-sn-glycerol (OAG), independently of protein kinase C activity. These are defining characteristics of specific TRPC channels. More detailed molecular analysis confirmed the expression of full-length TRPC2, TRPC3 and TRPC5 transcripts. These data indicate that CNP, acting via the NPR-C receptor, activates a NSCC that is at least partially carried by TRPC channels in cardiac fibroblasts.

Sensitivity of adult T-cell leukaemia lymphoma cells to tumour necrosis factor-related apoptosis-inducing ligand.

Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis in many transformed cells, but not in normal cells, and hence TRAIL has recently emerged as a novel anti-cancer agent. Adult T-cell leukaemia lymphoma (ATLL) is a neoplasm of T-lymphocyte origin aetiologically associated with human T-lymphotropic virus type 1 (HTLV-I), and is resistant to standard anti-cancer therapy. We thus characterized the sensitivity of ATLL cells to TRAIL in this study. Although most primary ATLL cells and cell lines expressed TRAIL death receptors on their surface, they showed only restricted sensitivity to TRAIL. Among the 10 ATLL cell lines examined, one was sensitive, but two had insufficient death-receptor expression, two had an unknown resistant mechanism with abrogation of the death signal upstream of caspase-8, and the remaining five showed attenuation of the signal in both extrinsic and intrinsic pathways by X-linked inhibitor of apoptosis and Bcl-2/Bcl-xL respectively. Furthermore, the level of HTLV-I tax expression was significantly correlated to TRAIL resistance. Interestingly, ATLL cells themselves expressed TRAIL on the cell surface. Constitutive production of TRAIL may offer resistance, thus allowing the development of TRAIL-resistant ATLL cells. Consequently, the resistant mechanism in ATLL cells against TRAIL was assigned to multiple factors and was not explained by a definitive single agent.

K+ currents regulate the resting membrane potential, proliferation, and contractile responses in ventricular fibroblasts and myofibroblasts.

Despite the important roles played by ventricular fibroblasts and myofibroblasts in the formation and maintenance of the extracellular matrix, neither the ionic basis for membrane potential nor the effect of modulating membrane potential on function has been analyzed in detail. In this study, whole cell patch-clamp experiments were done using ventricular fibroblasts and myofibroblasts. Time- and voltage-dependent outward K(+) currents were recorded at depolarized potentials, and an inwardly rectifying K(+) (Kir) current was recorded near the resting membrane potential (RMP) and at more hyperpolarized potentials. The apparent reversal potential of Kir currents shifted to more positive potentials as the external K(+) concentration ([K(+)](o)) was raised, and this Kir current was blocked by 100-300 muM Ba(2+). RT-PCR measurements showed that mRNA for Kir2.1 was expressed. Accordingly, we conclude that Kir current is a primary determinant of RMP in both fibroblasts and myofibroblasts. Changes in [K(+)](o) influenced fibroblast membrane potential as well as proliferation and contractile functions. Recordings made with a voltage-sensitive dye, DiBAC(3)(4), showed that 1.5 mM [K(+)](o) resulted in a hyperpolarization, whereas 20 mM [K(+)](o) produced a depolarization. Low [K(+)](o) (1.5 mM) enhanced myofibroblast number relative to control (5.4 mM [K(+)](o)). In contrast, 20 mM [K(+)](o) resulted in a significant reduction in myofibroblast number. In separate assays, 20 mM [K(+)](o) significantly enhanced contraction of collagen I gels seeded with myofibroblasts compared with control mechanical activity in 5.4 mM [K(+)](o). In combination, these results show that ventricular fibroblasts and myofibroblasts express a variety of K(+) channel alpha-subunits and demonstrate that Kir current can modulate RMP and alter essential physiological functions.

A comparative study of zygotic twinning and triplet rates in eight countries, 1972-1999.

Annual changes in twinning and triplet rates by zygosity were investigated in eight countries during the period 1972-1999 using vital statistics. The monozygotic (MZ) twinning rates in Denmark, Switzerland and the Slovak Republic remained more or less constant throughout this period, whereas those in England and Wales, the Federal Republic of Germany (Germany), the Netherlands, the Czech Republic and Japan increased significantly year by year. With the exception of the Slovak Republic, the dizygotic (DZ) twinning rate increased significantly year by year in each country. It was 2.9 times higher in Denmark and 1.5 times higher in Germany in 1999 than in 1972, and within the same range in the other countries. With two exceptions, the MZ triplet rates remained more or less constant in each country. On the other hand, the DZ and trizygotic (TZ) triplet rates increased significantly year by year in each country. The TZ rate increased 30-fold in Germany, 16.6-fold in Japan, 11.7-fold in Switzerland, 9.7-fold in the Czech Republic, 8.7-fold in the Netherlands, 6.4-fold in Denmark, 5.6-fold in England and Wales and 3.5-fold in the Slovak Republic. The higher DZ twinning rate and higher DZ and TZ triplet rates since 1983 have been attributed to the higher proportion of mothers being treated with ovulation-inducing hormones and in vitro fertilization (IVF) in Denmark, England and Wales, Germany, the Netherlands, Switzerland and Japan. After the introduction of fertility drugs and IVF, variations in the DZ twinning and triplet rates and the TZ triplet rates were not only due to biological factors, but also depended on the popularity of fertility drugs and IVF in each country. In the Slovak Republic, where human fertility might not be affected by some adverse environmental factors, the DZ:MZ ratio remained constant during the period 1972-1999.

Hippocampal heme oxigenase-1 in a murine cardiac arrest model.

Heme oxygenase-1 (HO-1) is a member of the heat shock protein family (HSP-32). It responds to thermal stress in cultured glial cells. To our knowledge. nothing is known about the expression and response of the HO-1 in cerebral ischemia. Therefore, we show here the induction of HO-1 in the brain of mice after global cerebral ischemia. HO-1-like immunoreactivity was detected at 12, 24, and 48 hours after ischemia recirculation. The HO-1-like immunoreactive cells were observed in astrocytes in the hippocampal dentate gyrus and CA1. The peak level of HO-1-like immunoreactivity was found 48 hours after the recirculation. HO-1-like immunoreactivity was observed in GFAP-positive astrocytes by use of a double immunostaining method. These results provide direct evidence for the induction and localization of HO-1 immunoreactivity in vivo in a mouse cerebral ischemia. We suggest that HO-1, produced in astrocytes after ischemia-recirculation, may directly affect neurons to protect from cell death.

A novel function of sphingosine-1-phosphate to activate a non-selective cation channel in human endothelial cells.

1. The Ca2+ entry pathway activated by sphingosine-1-phosphate (S1P) was examined in primary cultured vascular endothelial cells dispersed from human umbilical vein (HUVECs) by measuring intracellular Ca2+ concentration ([Ca2+]i), whole-cell membrane currents and single channel activity. 2. Application of S1P to HUVECs induced a slowly developing, sustained increase in [Ca2+]i. When Ca2+ was absent from the bathing solution, no S1P-induced changes in [Ca2+]i were observed. Tert-butylhydroquinone (BHQ), an inhibitor of Ca2+ pumps in endoplasmic reticulum, and histamine induced a transient elevation of [Ca2+]i in HUVECs. 3. Pretreatment of HUVECs with 100 ng x ml(-1) pertussis toxin (PTX) for 15 h almost abolished the S1P effect on [Ca2+]i and reduced the histamine effect to 40% of the control. The BHQ-induced elevation of [Ca2+]i was insensitive to PTX. 4. When whole-cell membrane currents were recorded using the amphotericin B-perforated-patch clamp technique while monitoring [Ca2+]i, application of S1P induced a tiny inward current (I(S1P)) which was followed by the elevation of [Ca2+]i. I(S1P) reversed at +20.0 +/- 2.7 mV under these experimental conditions. 5. When S1P was included in the pipette solution in the excised inside-out patch clamp configuration, single channel activity with a conductance of 17 pS was activated. This channel activity depended on the presence of intracellular GTP. 6. In summary, these results show that S1P has a novel effect in mammalian cardiovascular endothelium to activate a non-selective cation (NSC) channel in a GTP-dependent manner via a PTX-sensitive G-protein. This S1P-sensitive NSC channel acts as a Ca2+ entry pathway in endothelium.

Possible involvement of interferon regulatory factor 4 (IRF4) in a clinical subtype of adult T-cell leukemia.

Interferon regulatory factor (IRF) 4 is the lymphoid-specific transcription factor that is required for the proliferation of mitogen-activated T cells. IRF4 has been suggested to be involved in tumorigenesis because the overexpression of IRF4 caused the transformation of Rat-1 fibroblasts in vitro. Here, we show that IRF4 is constitutively expressed in adult T-cell leukemia (ATL)-derived cell lines, which were infected with human T-cell leukemia virus type-I, but hardly expressed the trans-activator protein, Tax. Similarly, constitutive expression of IRF4 was demonstrated in freshly isolated peripheral blood mononuclear cells (PBMC) from patients with either acute or chronic ATL. However, the high-level expression of IRF4 was specifically associated with acute ATL. With mitogen-activated PBMC from healthy donors, cell cycle analyses revealed that the induction of IRF4 occurred prior to cell cycle progression and the cells that had entered the cell cycle were predominantly IRF4-positive cells. In addition, ectopic expression of IRF4 in Rat-1 fibroblasts increased the S and G2 / M phase population significantly. Taken together, our results indicate that IRF4 is involved in the pathogenesis of ATL through its positive effect on the cell cycle, and that IRF4 can be used as a molecular marker of clinical subtype in ATL.

Infant mortality rates in single, twin and triplet births, and influencing factors in Japan, 1995-98.

The infant mortality rate (IMR) was analysed among single, twin and triplet births during the period from 1995 to 1998 using Japanese Vital Statistics. This study also investigated the effects of order of multiple births and of birthweight on the IMR. Proportions of neonatal deaths among total infant deaths were about 1/2 for singletons and 3/4 for both twins and triplets. Thus, to reduce the IMR, intensive care of multiple births is likely to be very important during the first month of life. The IMR was higher in males than females for both singletons and twins, but not in triplets. Relative risks of the IMR in multiples relative to singletons were 5-fold in twins and 12-fold in triplets. The IMR was higher in the second-born (18 per 1000 live births) than the first-born (16) twin and higher in the third-born (51) than the first-born (31) and the second-born (34) triplet. The higher risk in the second-born than the first-born twin may be related to delivery complications. The IMR decreased rapidly as birthweight increased in singletons, twins, and triplets. IMRs for < or =1500 g were 2.4 per 1000 live births in singletons, 5.9 in twins and 6.1 in triplets. The corresponding proportions of infant deaths were 75%, 33% and 10% respectively. The higher relative risks of multiple births are almost entirely the result of the lower birthweight distribution among twins and triplets. To reduce the IMR, birthweight is an important factor in twins, triplets and singletons. The overall early neonatal death rate decreased as gestational age rose in singletons, twins and triplets. For birthweights <1000 g, higher IMRs were related to gestational ages of <28 weeks.

C282Y and H63D mutations in the HFE gene have no effect on iron overload disorders in Japan.

OBJECTIVE: The gene responsible for hereditary hemochromatosis close to the human leukocyte antigen A locus was previously identified and designated as HFE. This study was performed to evaluate the clinical significance of two mutations, C282Y and H63D of HFE, in Japanese patients with hepatic iron overload. PATIENTS AND METHODS: We examined C282Y and H63D in 11 patients with primary hemochromatosis, 94 patients with chronic hepatitis C, 54 patients with miscellaneous liver diseases, and 151 healthy volunteers. The HFE gene region of DNA samples extracted from peripheral leukocytes was amplified by polymerase chain reaction. Restriction enzyme analysis was performed using SnaBI for C282Y and BclI for H63D. Direct sequence analysis was then performed when products suggested the presence of a mutation. RESULTS: All the subjects studied were free from C282Y. None of the patients with hemochromatosis had H63D. One patient with chronic hepatitis C was homozygous, and 4 patients were heterozygous for H63D. Two patients with alcoholic liver disease were heterozygous for H63D. The prevalence of chromosomes with H63D was 6/188 (3.2%) in patients with chronic hepatitis C, 2/108 (1.9%) in patients with miscellaneous liver diseases, and 8/302 (2.6%) in healthy volunteers. These differences were not significant. CONCLUSION: Our results suggested that neither C282Y nor H63D in HFE affect Japanese patients with hemochromatosis or chronic hepatitis C.

[3 cases of polymyalgia rheumatica (PMR), in which serum amyloid A was a useful index of the disease activity].

We encountered 3 cases of polymyalgia rheumatica (PMR), in which serum amyloid A (SAA) levels were correlated with clinical pictures after normalization of ESR and CRP levels. Therefore, it is suggested that SAA may be a useful index for evaluating the severity of intractable PMR. Case 1: The patient was a 75-year-old man. Although ESR and CRP levels were normalized after the administration of PSL (20 mg/day), myalgia persisted. When the dose of PSL was reduced, PMR recurred, which was relieved by administering 15 mg/day of PSL. However, myalgia recurred again when the dose of PSL was reduced thereafter. The elevated SAA level (33.0 micrograms/ml) was normalized by continuous administration of PSL without reducing the dose, resulting in the relief of myalgia. Case 2: The patient was a 65-year-old woman. The administration of PSL was initiated at a dose of 15 mg/day. Although myalgia was relieved, the symptom and elevated SAA levels persisted for approximately 3 months. Thereafter, PMR recurred, and SAA levels were markedly increased to 78.2 micrograms/ml. However, the symptom of PMR was eliminated by continuously administering PSL without reducing the dose. Although the dose of PSL was then reduced after the decrease in SAA levels, PMR did not recur. Case 3: The patient was an 88-year-old woman. Although the symptom of PMR was relieved by administering 15 mg/day of PSL, myalgia persisted. Since SAA levels were increased to 106 micrograms/ml, PSL was continuously administered without reducing the dose, resulting in the disappearance of the symptom and normalization of SAA levels approximately 3 months later. Although the dose of PSL was then reduced to 12.5 mg/day, PMR did not recur.

[High throughput pharmacology for drug discovery].

High Throughput Screening (HTS) now plays an important role in the discovery of new lead compounds for novel therapeutic targets. The advantage of HTS over the conventional method, now termed as Low Throughput Screening (LTS), is that valuable compounds can be selected rapidly from a large number of samples with minimal human involvement. In spite of the growing awareness of HTS, the importance of the LTS in the drug discovery and development is still not changed. Advances in pharmacogenomics will also provide us many pharmacological targets, and thus increase the number of compounds that should be assayed by HTS and LTS. In this review, we will first describe the outline of HTS. We will next describe new approaches to develop and brush up the LTS: 1) screening method of drugs acting on ion channels by voltage-sensitive fluorescent dye, 2) functional assay method using reconstituted smooth muscle fiber, and 3) organ culture method as a useful model of vascular proliferative disease. These approaches, which work cooperatively with HTS, will contribute greatly to the development of new drugs.

Estimated number of multiplets under 16 years using two sets of census data in Japan: 1990 and 1995.

Data for sets of multiples under 16 years of age were obtained from the population censuses of Japan in 1990 and 1995. These numbered 147,188 twin pairs, 1410 sets of triplets, 59 sets of quadruplets, and 3 sets of quintuplets in 1990, with the corresponding numbers in 1995 being 141,354, 2,211, 136 and 12, respectively. The total number of sets of multiples was 148,660 in 1990 and 143,713 in 1995. Twinning, triplet, quadruplet and quintuplet rates were estimated for each age. Rates of monozygotic twins and triplets remained constant age by age up to 15 years, while the dizygotic twinning rate, and rates of di- and tri-zygotic triplets decreased over the same period. Quadruplet and quintuplet rates also decreased. The accuracy of estimating number of multiples from census data is discussed using data on vital statistics.

The antiproliferative effect of mizoribine on rheumatoid synovial fibroblast mediated by induction of apoptosis.

In order to investigate the mechanism of anti-rheumatic action of mizoribine (MZR), antiproliferative effect of MZR on synovial fibroblasts obtained from rheumatoid arthritis (RA) patients were examined. To examine the effect of MZR on DNA synthesis, total radioactivity of 3H-thymidine (3H-TdR) incorporated into the synovial fibroblasts was measured. Also quantification of DNA fragmentation of synovial fibroblasts in the cultured supernatant and cell associated Bcl-2 protein, which is suspected of interfering with apoptosis, were performed with enzyme-linked immunosorbent assay. MZR suppressed 3H-TdR incorporation into synovial fibroblasts in a dose dependent fashion. Significant inhibition (P < 0.01) was attained at the concentration of more than 1 microgram/ml of MZR. However, induction of DNA fragmentation which is characteristic of apoptosis, were observed at only 10 micrograms/ml of MZR over 72 h-incubation significantly. In terms of the Bcl-2 expression of synovial fibroblasts, up to 10 micrograms/ml of MZR has no effect on the expression of this protooncogene bcl-2 expression. These results suggest that MZR might suppress the growth of rheumatoid pannus by inhibition of synovial fibroblast proliferation partially through the induction of apoptosis of synovial fibroblast without modulating Bcl-2 expression.