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Biomedical subjects

N Aida

Publications and source records attributed to N Aida.

At least 19 recordsLinked to original sources

Aberrant trafficking of a proteolipid protein in a mild Pelizaeus-Merzbacher disease.

Pelizaeus-Merzbacher disease (PMD) is a rare X-linked leukodystrophy caused by proteolipid protein 1 (PLP1) gene mutations. Previous studies indicated that proteolipid proteins (PLPs) with disease-associated mutations are misfolded and trapped in the endoplasmic reticulum (ER) during transportation to the cell surface, which eventually leads to oligodendrocyte cell death in PMD. Here we report a PMD patient with a very mild phenotype carrying a novel mutation (485G-->T) in exon 4 of the PLP1 gene that causes a Trp(162)Leu substitution in the protein. We also investigated intracellular trafficking of this mutant PLP in COS-7 cells. Transiently transfected mutant PLP(W162L) fused to an enhanced green fluorescent protein (EGFP) or a short peptide tag was not carried to the plasma membrane. However, in contrast to previous studies, this mutant PLP was not retained in the ER, indicating an escape of the newly translated protein from the quality control machinery. We also found that the mutant PLP accumulated in the nuclear envelope (NE) in a time-dependent manner. This mutant PLP, with its distribution outside the ER and a very mild phenotype, supports the idea that accumulation of misfolded mutant protein in the ER causes the severe phenotype of PMD.

Animals↗

Prophylactic cranial irradiation of acute lymphoblastic leukemia in childhood: outcomes of late effects on pituitary function and growth in long-term survivors.

It is well known that prophylactic cranial irradiation is highly effective in preventing central nervous system (CNS) relapse of acute lymphoblastic leukemia (ALL). Nevertheless, there have been very few reports on the late effects, especially pituitary function and growth, in long-term survivors who were treated with 18 Gy cranial irradiation in childhood. The subjects consisted of 35 children with ALL who were treated with prophylactic 18 Gy cranial irradiation at Kanagawa Children's Medical Center between October 1981 and February 1995. All patients received cranial irradiation after first attaining complete remission with induction chemotherapy, according to the treatment protocols prescribed by the Tokyo Children's Leukemia Study Group (TCLSG) and Tokyo Children's Cancer Study Group (TCCSG). Their ages at the time of cranial irradiation ranged from 2.2-15.0 years (mean 6.8). We evaluated their pituitary functions by measuring their pituitary hormone values 0.7-11.3 years (mean 6.0) after cranial irradiation and their growth by analyzing their height standard deviation score (SDS) at diagnosis of ALL and their final height SDS at the mean follow-up period of 8.2 years after cranial irradiation. Height SDS is defined as the difference between the patient's height and the mean height of their age and sex, divided by the standard deviation of their age and sex. Eight of 35 patients had ALL relapse, involving the bone marrow in seven patients and the CNS in only one. Six of the eight patients with relapse died 1.5-6.6 years after cranial irradiation and the other two patients were salvaged by further intensive therapies. The remaining 27 relapse-free patients have survived for 1.4-15.8 years (mean 10.1) after cranial irradiation. Twenty-six of the 29 survivors are long-term survivors of more than 5 years. Although there was one patient with an abnormal result in each value of growth hormone (GH), adrenocorticotropic hormone (ACTH), and prolactin (PRL), and two patients with abnormal results in thyroid-stimulating hormone (TSH) values, none of the patients had clinical symptoms of pituitary hormone abnormality and none required hormone supplements. The final height SDS decreased significantly compared with the height SDS at diagnosis of ALL in the long-term survivors (P = 0.001) and the height SDS of the patients who had received cranial irradiation at a young age tended to decrease gradually (P = 0.019). However, no patient showed severe growth failure. It is considered that prophylactic 18 Gy cranial irradiation plus chemotherapy for ALL in childhood can effectively prevent CNS relapse and is unlikely to produce clinically significant late effects, although it may cause slight pituitary hormone abnormality.

Adolescent↗

Clinicopathological study of a hilar nodule in the livers of long-term survivors with biliary atresia.

With the application of liver transplantation for patients with biliary atresia (BA), we have had the opportunity to review the clinicopathologic features of the native livers from 10 transplanted BA patients. A single large nodule at porta hepatis (hilar nodule) was noted in three of 10 patients, and an ill-defined nodule-like lesion at porta hepatis was present in two other patients. The three BA patients with hilar nodules were long-term survivors, compared to the patients with nodule-like and those without nodules. The hilar nodules measured between 5.0 cm and 8.0 cm and histologically, they were partly surrounded by fibrous septa with relatively well-preserved liver architectures and fewer inflammatory cells at the portal triads when compared to the surrounding cirrhotic lesions. No nuclear or cellular atypia was observed. Proliferating cell nuclear antigen labeling index was higher in the surrounding cirrhotic lesions than the hilar nodules. The nodule-like lesions at porta hepatis also showed similar light microscopic and immunohistochemical features as the hilar nodules. These hilar nodules did not seem to contain any malignant potential. The benign histology with relatively well-preserved liver architecture and the preferential site of occurrence at porta hepatis where bile seemed to flow more smoothly, suggested possible residues of less-affected hepatic tissues.

Biliary Atresia↗

3-D analysis of vascular and capsular invasion in thyroid follicular carcinoma.

To clarify the mechanism of vascular invasion (VI) and capsular invasion (CI) in thyroid follicular carcinoma (FC), 3-D reconstruction of tumor tissues, vessels and capsules was performed from serial sections in five FC and three follicular adenomas (FA). Outflow veins in the lesions were well developed under the capsule, narrowed just beneath the capsule, and dilated within the capsule. Both VI and CI were observed at the poststenotic intracapsular dilated part of outflow veins. The tumor tissue extended along the intracapsular horizontal veins which flowed in parallel with the capsule in VI, or along the vertical veins which directly flowed outside the capsule in CI. There was tumor tissue in the subendothelial layer of the outflow veins within the capsule. Intravascular tumor nests and nodular lesions within the capsule continued from the main tumors. It can be concluded from these results that most VI and CI may not be true invasions but pre-invasive lesions.

Adenocarcinoma, Follicular↗

Late recurrence of neuroblastoma stage 4S with unusual clinicopathologic findings.

The authors present unusual clinicopathologic findings of a patient with neuroblastoma stage 4S that recurred 11 years after induction of complete remission with chemotherapy. A 12-year-old girl presented with recurrent tumor in the liver. Urinary catecholamine metabolites were within normal range in contrast to the increased values at initial presentation. She underwent left lateral segmentectomy and biopsy of the right lobe. Histologic analysis of the recurrent tumor showed undifferentiated neuroblastoma intermingled with mature ganglioneuromatous lesions. There also were scattered ganglioneuromatous lesions throughout nontumorous area of the liver. Although multimodal intensified treatments including autologous bone marrow transplantation were performed, the patient died of obstinate recurrent tumor at age 14 years. The clinicopathologic findings suggested dedifferentiation from the ganglioneuromatous lesion rather than ordinary recurrence of the primary tumor. The current case and the literature review may indicate that long-term follow-up would be necessary for neuroblastoma stage 4/4S cases. J Pediatr Surg 36:953-955.

Child↗

Congenital absence of the portal vein and role of liver transplantation in children.

BACKGROUND/PURPOSE: Congenital absence of the portal vein (CAPV) is a subtype of congenital portosystemic shunt, which can cause a broad spectrum of clinical manifestations. The authors report on 4 patients with CAPV including a boy with CAPV-associated encephalopathy, which was resolved effectively by liver transplantation (LT). METHODS: The case records of 4 pediatric patients with CAPV who were referred to the author's institution between 1984 and 1999 were reviewed. RESULTS: The patients (3 boys and 1 girl) ranged in age at diagnosis from 0.8 to 14 years. Two patients had growth retardation or disturbed consciousness, and the other 2 had no specific manifestations. Not only high serum levels of bile acids, ammonia, and transaminases but also low plasma levels of branched-chain amino acids were common laboratory findings. The absent portal vein was replaced by a large portosystemic shunt, which connected the splanchnic vein to the inferior vena cava or the left renal vein. Two patients survived without any symptoms, but 1 with growth retardation died of hepatic failure. The other with encephalopathy did not respond to medical therapy and underwent LT, which resolved symptoms and metabolic disorders effectively. CONCLUSIONS: Patients with CAPV do not always have a good prognosis. They should be followed up with careful observation of their symptoms, hepatic function, and metabolic abnormalities. LT might be indicated for patients with symptomatic CAPV unresponsive to medical therapy.

Adolescent↗

Congenital dyserythropoietic anemia type 1 with fetal onset of severe anemia.

We report a patient with congenital dyserythropoietic anemia type 1 with characteristic anomalies and two novel clinicopathologic presentations: intrauterine onset of severe anemia resulting in cardiac failure and relatively mild dyserythropoietic features on bone marrow aspiration in contrast to severity of anemia. After repeated transfusions and a trial of erythropoietin administration, the patient died from respiratory infection at age 7 months. Autopsy revealed characteristic dyserythropoietic features of the bone marrow by light microscopy and electron microscopy, which confirmed a diagnosis of congenital dyserythropoietic anemia type 1.

Anemia, Dyserythropoietic, Congenital↗

Radiation therapy for life- or function-threatening infant hemangioma.

PURPOSE: To assess the effectiveness and long-term results of radiation therapy in infants with life- or function-threatening hemangiomas. MATERIALS AND METHODS: Thirteen patients with life- or function-threatening hemangiomas (eight male, five female; age range, 0-8 months; median age, 2 months) were treated with radiation therapy. Life-threatening hemangiomas were treated with five fractions of radiation per week, and function-threatening hemangiomas were treated with two fractions per week. A median dose of 10 Gy was delivered to each hemangioma. The presence of residual hemangiomas, skin changes, functional problems, and growth delay was evaluated. RESULTS: All patients with Kasabach-Merritt syndrome (KMS) showed regression of the hemangioma and an increase in platelet counts to greater than 100,000 per cubic millimeter (1.0 x 10(11) per liter) within 40 days after radiation therapy. The treatment field was inadequate in two patients who required reirradiation or a change of treatment portal. With the exception of the patients with KMS, all but one patient experienced relief from symptoms in 40 days. Severe long-term radiation-related morbidity was noted in one patient who required reirradiation for a relapsed hemangioma. CONCLUSION: Radiation therapy (in doses of < or = 10 Gy in 2-Gy fractions) is indicated for life-threatening hemangiomas and for some function-threatening hemangiomas.

Adolescent↗

Covalent modifier NEDD8 is essential for SCF ubiquitin-ligase in fission yeast.

A ubiquitin-like modifier, NEDD8, is covalently attached to cullin-family proteins, but its physiological role is poorly understood. Here we report that the NEDD8-modifying pathway is essential for cell viability and function of Pcu1 (cullin-1 orthologue) in fission yeast. Pcu1 assembled on SCF ubiquitin-ligase was completely modified by NEDD8. Pcu1(K713R) defective for NEDD8 conjugation lost the ability to complement lethality due to pcu1 deletion. Forced expression of Pcu1(K713R) or depletion of NEDD8 in cells resulted in impaired cell proliferation and marked stabilization of the cyclin-dependent kinase inhibitor Rum1, which is a substrate of the SCF complex. Based on these findings, we propose that covalent modification of cullin-1 by the NEDD8 system plays an essential role in the function of SCF in fission yeast.

Amino Acid Sequence↗

Congenital primitive epithelial tumor of the liver showing focal rhabdoid features, placental involvement, and clinical features mimicking multifocal hemangioma or stage 4S neuroblastoma.

We describe an unusual case of congenital primitive epithelial tumor of the liver with focal rhabdoid features. The present case is unique and informative in the following aspects: (1) a first case of congenital epithelial tumor of the liver with no hepatocytic differentiation but focal rhabdoid features, (2) clinical similarities to multicentric hemangioma or stage 4S neuroblastoma, (3) diagnosis obtained from histological examination of the placenta immediately after birth.

Adult↗

Epithelioid leiomyosarcoma in a non-immunocompromised infant: additional differential diagnosis of pediatric "round cell tumors".

We report an 18-month-old Japanese girl with purely epithelioid leiomyosarcoma presenting as a huge intraabdominal mass. The patient had been well from birth and had shown no signs of immunodeficiency. She was negative for human immunodeficiency virus. Blood examination revealed elevated serum neuron specific enolase (NSE). Histologically, the tumor was comprised of solid growths of round or polygonal cells with vesicular nuclei and often vacuolated cytoplasm rich in glycogen. The tumor cells were positive for vimentin, NSE, and MIC2, and were negative for desmin and neurofilament. The age, clinical presentation, and histologic findings mostly favored Ewing's sarcoma/primitive neuroectodermal tumor. Silver stain, however, demonstrated well-developed reticulin fibers often outlining individual tumor cells. An expanded panel of immunostains showed that the tumor cells were intensely positive for smooth muscle actin, and ultrastructural study revealed abundant fine cytoplasmic filaments with focal subsarcolemmal densities, various amounts of glycogen, and irregularly arranged, thick basal lamina. The diagnosis of epithelioid leiomyosarcoma was made. Following reduction in tumor size by chemotherapy, the serum NSE level was normalized. From the surgical finding, the primary site was presumed to be the urachus or the urinary bladder dome. Although extremely rare, epithelioid leiomyosarcoma should be added in the list of differential diagnoses of pediatric "round cell tumors."

Abdominal Neoplasms↗

Clinicopathologic study of mass-screened neuroblastoma with special emphasis on untreated observed cases: a possible histologic clue to tumor regression.

Spontaneous regression and maturation of neuroblastoma (NB) are well documented and occur frequently in infants, including those detected by mass screening. To seek histologic clues for regression/maturation in mass-screened NB, clinicopathologic features of 12 tumors that were resected after 2 to 18 months of untreated observation were reviewed. Unobserved screened and age-matched unscreened patients were also studied. To evaluate the possible important role of apoptosis, apoptotic cells were detected by in situ deoxyribonucleic acid (DNA) nick end labeling and immunohistochemical stain for activated caspase-3. Nests with a varying degree of reduced cellularity ("less cellular" and "hypocellular" nests) were common in patients younger than 18 months of age, and were rare in older patients. Two characteristic cells, which have not been focused previously, were frequent, especially in the hypocellular nests. One showed amorphic eosinophilic cytoplasm with pyknotic nuclei and the other contained plump cytoplasm with well-maintained nuclei. These cells were also observed in 89% of the unobserved screened NBs and 79% of the age-matched unscreened patients with good outcome, whereas they could not be confirmed in any of the age-matched unscreened NBs with poor outcome. The amorphic and plump cells were negative for activated caspase-3 and in situ DNA nick end labeling. From these results, the authors hypothesize that these cells most likely represent a degenerative process, in either a state before the activation of caspase-3 or a caspase-independent form of cell death. The presence of less cellular and hypocellular nests with amorphic/plump cells may serve as one of the important clues in predicting tumor prognosis.

Age Factors↗

Frontonasal dysplasia, macroblepharon, eyelid colobomas, ear anomalies, macrostomia, mental retardation, and CNS structural anomalies: another observation.

We report a Japanese girl with brachycephaly, a wide forehead, hypertelorism, macroblepharon with eyelid colobomas, ectropion, a broad nasal root, a depressed nasal tip, macrostomia, a small and grooved chin, ear anomalies, a structural anomaly of the corpus callosum, dilatation of the fourth ventricle, a urogenital sinus, and mental retardation. Cause and inheritance are unknown.

Abnormalities, Multiple↗

Natural course of neuroblastoma detected by mass screening: s 5-year prospective study at a single institution.

PURPOSE: To describe various favorable courses of neuroblastoma (NBL) detected by mass screening and to present our observation program as a temporary treatment option, to be used until a final decision is made regarding the mass screening program for 6-month-old infants. PATIENTS AND METHODS: Between October 1993 and November 1999, 26 of 51 patients with NBL detected by mass screening were enrolled in our observation program. The criteria for observation included urinary vanillylmandelic acid (VMA) and homovanillic acid (HVA) levels less than 50 microg/mg creatinine, smaller tumor size (< 5.0 cm), preoperative status, and granted informed consent. Patients were divided into four groups according to changes in urinary VMA and HVA values and tumor size. Patients who no longer fulfilled criteria underwent surgery. RESULTS: The observation period ranged from 4 to 73 months. Urinary VMA and HVA levels decreased in 19 of 26 patients, often by age 16 months. Eighteen patients had regressing tumors, and in 10 of these cases, the tumor was undetectable or barely detectable by imaging techniques. Four patients younger than 12 months had increased tumor marker levels and tumor volume, histologically reflecting neuroblastic proliferation. The remaining three patients, all older than 18 months, had varied tumor marker levels but increased tumor volume, histologically reflecting an increase in Schwann cells. No upgrading of tumor stage or unfavorable biologic factor was noted in any patient. CONCLUSION: None of our patients showed evidence of transition from favorable to unfavorable prognosis, a finding that points to a reduction in the significance of screening as a public health measure. Until results of ongoing screening trials involving older patients have been evaluated, the observation program can be used as a temporary measure to avoid, with little risk, unnecessary surgical intervention.

Abdominal Neoplasms↗

Noonan syndrome and cavernous hemangioma of the brain.

We present two patients with multiple characteristics that occur in Noonan phenotype and cavernous hemangioma of the brain. The first patient, who had been diagnosed radiographically as having a cavernous hemangioma in the left basal ganglia at age 15 years, developed massive intracerebral hemorrhage, resulting in sudden death at home at 19 years. The second patient, who was diagnosed radiographically as having a cavernous hemangioma in the left parietal lobe at age 17 years, is being followed carefully (the patient is currently 18 years old). A review disclosed four cases of structural cerebrovascular abnormalities with or without subsequent hemorrhage. Neither these four patients nor our two patients had any severe anomalies in the heart or large vessels, which are frequently seen in patients with Noonan syndrome. Cerebrovascular abnormalities might have a significant influence on the prognosis of patients with Noonan syndrome, especially those having no severe abnormalities in the heart or large vessels.

Adolescent↗