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Shinpei Nakazawa

Publications and source records attributed to Shinpei Nakazawa.

35 records · Page 2Linked to original sources
PubMed2004

[Case of severe motor and intellectual disabilities presenting with partial central diabetes insipidus triggered by infection].

We report a 42-year-old woman with severe motor and intellectual disabilities (SMID) who showed partial central diabetes insipidus during severe pneumonia. Serum sodium levels were previously within the upper normal range from 140 to 147 mEq/L. During pneumonia, however, serum sodium rose rapidly to reach 185 mEq/L. The daily urinary volume exceeded the daily intake of water. Nasal administration of 1-desamino-8-D-arginine vasopressin (DDAVP) reduced the daily urinary volume and the serum sodium level to normal ranges. Consequently, we diagnosed her as having central diabetes insipidus (DI). She required a smaller dose of DDAVP (2.5 microg/day) than usual DI (5-15 microg/day) to maintain normal urinary volume and the serum sodium level for seven months. After the nasal administration of DDAVP was discontinued, the serum sodium levels again returned to within the upper normal range. A water deprivation study demonstrated poor elevation of both plasma antidiuretic hormone (ADH) level (range, 0.5-2.0 pg/ml) and urine osmolarity (peak level, 552 mOsm/kgH2O) despite the elevation of plasma osomolarity, suggesting latent partial central DI. Water balance and serum electrolyte levels should be closely monitored in cases of SMID.

Adult↗
PubMed2004

[NSE-positive lymphoblastic lymphoma in a boy with cutaneous involvement, giant splenomegaly, and hyper-gamma globulinemia].

We report a 6-year-old boy who was diagnosed as having neuron-specific enolase (NSE)-positive pro-T cell type lymphoblastic lymphoma preceded with a variety of symptoms such as skin rash, giant splenomegaly, and hyper-gamma globulinemia. He first showed cervical lymphadenopathy in June 1999, followed by a fever of unknown origin with atypical erythema, hepatosplenomegaly, and a few lymphoblastoid cells present in the bone marrow in September. However, no specific treatments were started at this point because a cervical lymph node biopsy failed to show malignancy and the patient's signs and symptoms resolved spontaneously. Two months later, oral prednisolone therapy was started due to recurrence of the fever and erythema, but resulted in exacerbation of the skin lesions and generalized lymphadenopathy. A biopsy of the right inguinal lymph node performed in January 2000 revealed proliferation of lymphoblastic cells positive for CD3, CD5 and NSE with a rearrangement of T cell receptor gene Jdelta, leading to the diagnosis of lymphoblastic lymphoma. After intensified chemotherapy, he received an autologous peripheral blood stem cell transplantation and has been in complete remission for 4 years.

Child↗
PubMed2003

Transient decrease in the CD45RA expression on T lymphocytes in neonates with fetal distress.

To determine the expression of CD45 isoforms on T lymphocytes in neonates with fetal distress and to evaluate its diagnostic accuracy, peripheral blood samples were examined in 53 neonates who were classified into one of three groups: group I: 'control' group (n = 23), group II: 'mild distress' group (n = 15), and group III: 'moderate distress' group (n = 15). The expression of CD3 (mean +/- SD 24.2 +/- 10.1%), CD4 (23.0 +/- 5.7%), and CD45RA (27.3 +/- 9.6%) on total lymphocytes and the expression of CD45RA on CD4+ T lymphocytes (13.7 +/- 4.7%) in group III were significantly lower than in the other two groups 0-3 days after birth. Sensitivity and specificity of the CD45RA expression on CD4+ T lymphocytes for discrimination of group III were calculated as 0.79 and 1.0, respectively, when the cutoff value was 22.7%. The low CD3, CD4, and CD45RA expression returned to normal levels 10 days and more after birth. There were no differences in the CD8 and CD45RO expression between the groups. We conclude that CD4+ T lymphocytes from neonates with fetal distress show a transient decrease in the CD45RA expression without an increase in the CD45RO expression, and, therefore, analysis of the CD45 isoform expression is useful for laboratory evaluation of fetal distress.

CD3 Complex↗
PubMed2003

Effects of sodium in hydration solution on plasma methotrexate concentrations following high-dose methotrexate in children with acute lymphoblastic leukemia.

PURPOSE: To test whether a higher sodium dose in the hydration solution may facilitate faster methotrexate (MTX) elimination as compared with a lower sodium dose following high-dose MTX (HDMTX) treatment. METHODS: Intravenous solutions with alternate doses of sodium (regimen A 70 mEq/l, regimen B 100 mEq/l) were given to 30 children with acute lymphoblastic leukemia in two courses of HDMTX in a randomized crossover fashion. The plasma MTX concentrations every 24 h from the beginning of MTX administration and the adverse events associated with HDMTX were compared between the two hydration regimens. RESULTS: The plasma MTX concentrations were similar in the two hydration regimens at 24 h (A 50.9+/-7.4 vs B 40.9+/-5.4 microM, means+/- SE, P=0.17), but was significantly lower in regimen B at 48 and 72 h (A 0.65+/-0.17 vs B 0.27+/-0.03 microM, P=0.04; and A 0.14+/-0.03 vs B 0.05+/-0.01 microM, P=0.003). The time during which MTX plasma concentrations exceeded 0.1 microM was significantly longer in regimen A than in regimen B (A 3.83+/-0.18 vs B 3.13+/-0.06 days, P=0.001). The incidences of adverse events were similar between the two regimens ( P=0.78), and severe adverse events were not seen in either regimen. CONCLUSIONS: Hydration with a higher sodium dose facilitated faster MTX elimination following HDMTX. Sodium may have a beneficial effect on MTX-induced nephrotoxicity.

Adolescent↗
PubMed2003

Development of the prefrontal lobe in infants and children: a three-dimensional magnetic resonance volumetric study.

Relatively little is known about normal prefrontal lobe development. We used three-dimensional magnetic resonance imaging (MRI)-based brain volumetry to characterize developmental changes in prefrontal lobe volumes in infants and children. Prefrontal volumes were determined in 30 subjects aged 5 months to 18 years (221 months) and 3 adults aged 28-39 years (324-468 months). Images were acquired on a 1.5-T MRI system using T1-weighted gradient-echo sequences. Volumes of the frontal and prefrontal lobes were determined using a workstation, and the prefrontal-to-frontal volume ratio was calculated. Prefrontal lobe volume increased slowly until 8 years (96 months) of age, contrasting sharply with rapid growth between 8 and 14 years (96 and 168 months). The prefrontal-to-frontal volume ratio increased with age as a sigmoid growth curve. A prefrontal growth spurt occurs in late childhood. Knowledge of prefrontal lobe development is essential for understanding cognitive development and dysfunction.

Adolescent↗
PubMed2003

Age shifts frontal cortical control in a cognitive bias task from right to left: part I. Neuropsychological study.

Two functionally and neurally distinct cognitive selection mechanisms involve the prefrontal lobes: those based on internal representations (context dependent) and those involving exploratory processing of novel situations (context independent). We used a cognitive bias task (CBT) representing contextual reasoning to correlate lateralization with age in the frontal lobes. Subjects included 37 healthy right-handed male children and adolescents (age range, 5-18 years). Controls were 19 right-handed men from 20 to 30 years old. A computer-presented version of the original card-choice task simplified, modified for children was used (modified CBT; mCBT). Simple visual stimuli differed dichotomously in shape, color, number, and shading. A target object presented alone was followed by two choices from which subjects selected according to preference. Considering all four characteristics, similarity between target and subject choice was scored for 30 trials. A high score implied a context-dependent response selection bias and a low score, a context-independent bias. Similarity increased significantly with age. The youngest children (5-7 years) scored lower than ages from 11 years to adulthood. Between 7 and 9 years, scores began to increase with age to reach an adult level by age 13-16. Young children showed context-independent responses representing right frontal lobe function, while adolescents and adults showed context-dependent responses implicating left frontal lobe function. The locus of frontal cortical control in right-handed male subjects thus shifts from right to left as cognitive contextual reasoning develops.

Adolescent↗
PubMed2003

[Development of severe aplastic anemia in a girl with Hashimoto's thyroiditis and papillary thyroid carcinoma].

A 14-year-old girl was admitted because of general fatigue and cervical lymphadenopathy. She showed bilateral struma (IInd degree) and enlargement of her left cervical lymph nodes. Laboratory data revealed neutropenia (219/microliter) and thrombocytopenia (Plt 5.1 x 10(4)/microliter) with mild anemia (Hb 11.1 g/dl), and the bone marrow aspirate and biopsy specimens showed hypocellularity. In addition, auto-antibodies against thyroid peroxidase (TPO) and thyroglobulin (TG) were highly elevated. Computed tomography of the neck showed a nodule in the left thyroid lobe with marked lymphadenopathy, and fine needle aspiration biopsy demonstrated papillary thyroid carcinoma with Hashimoto's thyroiditis and metastasis to the lymph nodes. One month after left thyroid lobectomy and cervical lymphadenectomy, the patient's condition progressed to very severe aplastic anemia, and she received immunosuppressive therapy consisting of cyclosporin A and anti-thymocyte globulin. Hematologically, partial and complete responses were obtained three and six months later, respectively. Of interest, anti-TPO and TG antibody titers remarkably decreased after immunosuppressive therapy. The patient had HLA-DR 2(DRB 1*1501) and DR 8(DRB 1*0802). The former is frequently found in patients with cyclosporin A-dependent aplastic anemia, and the latter is frequently found in Asian patients with Hashimoto's thyroiditis, suggesting an underlying autoimmune background for the simultaneous outbreak of aplastic anemia and Hashimoto's thyroiditis complicated by thyroid carcinoma.

Adolescent↗
PubMed2002

TNF-related apoptosis-inducing ligand (TRAIL) frequently induces apoptosis in Philadelphia chromosome-positive leukemia cells.

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and Fas ligand (FasL) have been implicated in antitumor immunity and therapy. In the present study, we investigated the sensitivity of Philadelphia chromosome (Ph1)-positive leukemia cell lines to TRAIL- or FasL-induced cell death to explore the possible contribution of these molecules to immunotherapy against Ph1-positive leukemias. TRAIL, but not FasL, effectively induced apoptotic cell death in most of 5 chronic myelogenous leukemia-derived and 7 acute leukemia-derived Ph1-positive cell lines. The sensitivity to TRAIL was correlated with cell-surface expression of death-inducing receptors DR4 and/or DR5. The TRAIL-induced cell death was caspase-dependent and enhanced by nuclear factor kappa B inhibitors. Moreover, primary leukemia cells from Ph1-positive acute lymphoblastic leukemia patients were also sensitive to TRAIL, but not to FasL, depending on DR4/DR5 expression. Fas-associated death domain protein (FADD) and caspase-8, components of death-inducing signaling complex (DISC), as well as FLIP (FLICE [Fas-associating protein with death domain-like interleukin-1-converting enzyme]/caspase-8 inhibitory protein), a negative regulator of caspase-8, were expressed ubiquitously in Ph1-positive leukemia cell lines irrespective of their differential sensitivities to TRAIL and FasL. Notably, TRAIL could induce cell death in the Ph1-positive leukemia cell lines that were refractory to a BCR-ABL-specific tyrosine kinase inhibitor imatinib mesylate (STI571; Novartis Pharma, Basel, Switzerland). These results suggested the potential utility of recombinant TRAIL as a novel therapeutic agent and the possible contribution of endogenously expressed TRAIL to immunotherapy against Ph1-positive leukemias.

Amino Acid Chloromethyl Ketones↗
PubMed2002

The association of Ala45Thr polymorphism in NeuroD with child-onset Type 1a diabetes in Japanese.

Recently Iwata et al. reported that the polymorphism in NeuroD exon 2(Ala45Thr) was associated with adult-onset Type 1 diabetes in Japanese. Furthermore, the mutations in the NeuroD as a regulator of insulin transcription have been reported to result in Type 2 diabetes. We, therefore, aimed to clarify the role of this Ala45Thr polymorphism in the susceptibility to Type 1a, immune-mediated, diabetes of child-onset Japanese patients. Eighty patients with child-onset Type 1 diabetes were examined along with 121 non-diabetic subjects as the controls. The polymorphism in Ala45Thr was defined using the PCR-RFLP method. The GAD Ab, IA-2 Ab, HLA-DRB1 genotypes and residual beta-cell function at 3 years from onset were evaluated in relation to the difference in this polymorphism. The frequency of the Ala45Thr heterozygotes was significantly higher in the Type 1 diabetic patients than in the controls (21.3 versus 9.9%, P=0.0252). The frequency of loss of beta-cell function was higher in heterozygotes patients than in wild type homozygotes patients (P=0.0112). Type 1 diabetic patients with DRB1*0901 allele showed a significantly higher frequency, 27.9%, of the Ala45Thr variant than the controls (P=0.0041). In conclusion, the Ala45Thr polymorphism contributes to the risk of development of, and to the early deterioration of beta-cell function, in Type 1a diabetes among the Japanese population.

Adolescent↗
PubMed2002

Effects of growth hormone on testicular dysfunction induced by cyclophosphamide (CP) in GH-deficient rats.

Growth hormone (GH) is known to accelerate spermatogenesis and maintain gonadal function. In this study, we evaluated the effect of GH on recovery from testicular damage induced by cyclophosphamide (CP). Eleven- to fourteen-week-old GH-deficient Lewis rats (dw/dw) were divided into 4 groups (n = 10 each), with one group serving as controls. In the CP group, CP was intravenously administered in daily doses of 50 mg/kg for 2 days, followed by daily doses of 10 mg/kg for the next 3 days. In the GH group, rat GH was subcutaneously administered at a daily dose of 0.3 mg/kg until the rats were sacrificed. In the CP/GH group, GH and CP administration were started simultaneously. In the CP/preGH group, GH administration was started 14 days before CP administration. Five rats from each group were sacrificed at days 14 and 28 after administration of CP. Spermatogenesis was then evaluated morphometrically by counting numbers of cells at several stages of the spermatogenic cycle. On day 14, there were no significant differences in the numbers of the spermatocytes between CP and CP/GH group. On day 28, the numbers of spermatocytes and motility of spermatozoa in CP/GH group were greater than those of CP group were. In the CP/preGH group, these effects of GH administration were not observed. These results suggested that administration of GH improved testicular function damaged by CP under GH-deficient condition, when GH and CP administration are started simultaneously.

Animals↗
PubMed2002

[Measurement of the frontal and prefrontal lobe volumes in children with malnutrition by three dimensional magnetic resonance imaging scan].

To evaluate the effects of malnutrition in early life on the growth of the frontal and prefrontal lobes, we quantitatively measured the volumes of the frontal and prefrontal lobes by three dimensional (3-D) MRI in three children (1 year 2 months to 2 years 5 months) with malnutrition. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. The data obtained were compared with those of 16 normal subjects (13 children aged 5 months to 14 years, and 3 adults aged 27 to 39 years). The volumes of the frontal and prefrontal lobes in the subjects were smaller compared with age matched controls. The results suggest that malnutrition in early life affects the growth of the frontal and prefrontal lobes.

Adolescent↗
PubMed2002

[Measurements of the frontal and prefrontal lobe volumes by three dimensional magnetic resonance imaging scan--III. Analysis of sex differences with advanced age].

To determine whether there is sex difference in the growth of the frontal and prefrontal lobes, we quantitatively measured the volume of these lobes by three dimensional (3-D) MRI in healthy 12 males (5 months to 39 years) and six females (1 year 11 months to 27 years). The left and right lobes were studied separately. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. In males, the left to right ratio (L/R ratio) of the frontal and prefrontal lobes increased with age. On the contrary, in females, L/R ratio of the frontal and prefrontal lobes showed no significant change with advancing age. These results highlighted sex-specific maturational changes of the frontal and prefrontal lobes and suggested that quantitative data on the frontal and prefrontal lobe are important in interpreting brain abnormalities in children with developmental disorders.

Adolescent↗
PubMed2002

[The evaluation of lateralized frontal lobe function in the patients with autistic or attention deficit/hyperactivity disorder].

The prefrontal lobes are involved in two functionally distinct cognitive selection mechanisms: processing based on internal representation, such as planning (context-dependent reasoning) and exploratory processing of novel cognitive situations (context-independent reasoning). On the basis of this working hypothesis, a cognitive bias task (CBT; Goldberg, 1994), designed as an activation procedure representing contextual reasoning, was used to explore developmental disorders of lateralization in the frontal lobes in autistic disorder and attention deficit/hyperactivity disorder (ADHD). The subjects included 3 patients with autistic disorder, 4 with ADHD. Ten normal right-handed males served as controls. In CBT, a high score indicated consistency of choice: a context dependent selection bias, and a low score showed independent selection bias. The autistic group showed a score significant lower than those in controls (p < 0.01). The ADHD group had also a lower score. These findings implicate a deficit in the development of hemispheric specialization in the symptoms of these developmental disorders.

Attention Deficit and Disruptive Behavior Disorder↗
PubMed2002

[Ictal SPECT and paired stimulation SEP recovery curve in a patient with paroxysmal kinesigenic choreoathetosis].

Paroxysmal kinesigenic choreoathetosis (PKC) is a rare and benign disorder with its onset in childhood. PKC generally improves with age, and its pathophysiology has not been revealed. We recorded both ictal and interictal SPECT in a 14-year-old girl with PKC. Ictal SPECT showed a significant decrease in blood flow in the caudate nucleus contralateral to the limb showing an involuntary movement. We also examined paired-pulse stimuli somatosensory evoked potential (SEP) of the same patient. Recovery pattern of P25 and N33 components was normal and comparable to 5 healthy volunteers, suggesting the absence of cortical hyperexcitability. These results suggest dysfunction or immaturity of the indirect pathway of basal ganglia in PKC, as well as the hyperexcitability of the descending pathway.

Adolescent↗