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Y Yamashiro

Publications and source records attributed to Y Yamashiro.

At least 37 records · Page 2Linked to original sources
PubMed2001

Quantitative analysis of telomerase activity and telomerase reverse transcriptase expression in renal cell carcinoma.

To investigate the relationship between the telomerase activity levels and clinicopathological features of tumors, we quantified the telomerase activities of 23 renal cell carcinomas (RCCs) and four non-cancerous tissues, using a modified telomeric repeat amplification protocol assay, and assessed the hTERT mRNA levels of these samples by reverse transcription-polymerase chain reaction analysis. Elevated levels of telomerase activity had correlation with tumor stages as well as the degree of nuclear grades. Our findings suggested that telomerase activity is a useful indicator for tumor aggressiveness in RCCs. However, hTERT mRNA levels in RCCs had no correlation with nuclear grades and tumor stages. The telomerase activities and the hTERT mRNA levels in cancer cells were not always in parallel. These results suggested that telomerase activity is regulated in a posttranscriptional manner as well as a post-translational manner in tumor cells.

Adult↗
PubMed2001

Angiotensin converting enzyme gene polymorphism in primary vesicoureteral reflux.

We studied the insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE) gene in 78 patients with primary vesicoureteral reflux (VUR), and examined renal function by dimercaptosuccinate (DMSA) renoscintigraphy and diethylenetriamine-penta-acetic acid (DTPA) renogram in each genotype. Patients were classified into three genotypes according to the ACE gene I/D polymorphisms: 32 in II genotype, 36 in ID, and 10 in DD. The incidence of presumably congenital unilateral small kidneys was high in DD patients (70%). Glomerular filtration rate obtained from DTPA renogram was 120.7+/-35.7 ml/min (expressed as mean+/-SD) in II genotype, 111.7+/-33.3 in ID, and 88.0+/-18.0 in DD. The total quantitative DMSA tracer uptake of both kidneys was also low in patients with the D allele. This study shows that the D allele of ACE gene is closely related to small congenital kidneys with refluxing ureters in patients with primary VUR, and in accordance with previous reports, this allele is also related to the progression of reflux nephropathy.

Alleles↗
PubMed2001

Combined pharmacotherapy for nocturnal enuresis.

Nocturnal enuresis is a common childhood disorder. Tricyclic antidepressants and anticholinergic agents have been the well accepted pharmacological treatment for this disorder and are efficacious in 40-70% and 10-50% of cases, respectively. The present study was performed to evaluate the effect of a combined treatment of tricyclic antidepressant and an anticholinergic agent. Twenty-two children aged 6-12 years with primary monosymptomatic nocturnal enuresis who did not prefer to use a conditioning alarm were given a combined treatment of these drugs. After a control period of 1 month, each patient was treated for 6 months and then observed for 3 months. A 30-mg dose of amitriptyline or imipramine was given with either 2-4 mg oxybutinin or 10-20 mg propiverine. Efficacy was determined relative to the number of wet nights per week compared with the control period, with more than a 50% decrease in wet nights per week taken to indicate efficacy. The mean wet nights per week decreased from 6.1 to 1.7 (P<0.01), and efficacy was established in 20 patients (90.9%). Relapses occurred in 60.0% of patients during the follow-up period. No significant side effects were observed. The efficacy of the combined therapy in monosymptomatic nocturnal enuresis appears to be greater than that reported for either drug alone, and therefore can be a choice of treatment in order to motivate children with nocturnal enuresis.

Amitriptyline↗
PubMed2001

Nutcracker phenomenon demonstrated by three-dimensional computed tomography.

We report a 15-year-old girl with nutcracker syndrome (NCP) in whom three-dimensional helical computed tomography (3D helical CT) was useful for diagnosis; angiographic imaging using 3D helical CT provided fine outlines of the vascular structures in NCP, i.e., a compression of the left renal vein between the aorta and the superior mesenteric artery and the abnormal acute angle between them. Thus, a 3D helical CT enables precise depiction of the anatomical characteristics of renal vasculature and, therefore, may be a useful alternative imaging technique instead of conventional examinations, such as invasive venography or digital subtraction angiography. Further study in a large number of children with vascular abnormalities would be worthwhile.

Adolescent↗
PubMed2001

Systemic effects of transdermal testosterone for the treatment of microphallus in children.

OBJECTIVES: To elucidate the metabolic effects of topical testosterone for the treatment of microphallus in children. METHODS: We administered 5% testosterone ointment to 50 prepubertal boys for the treatment of microphallus, allowing us to observe its metabolic effect on plasma concentrations of testosterone as a marker of transdermally absorbed testosterone, insulin-like growth factor (IGF)-I as a marker of growth hormone secretion status, and osteocalcin as a marker of bone metabolic turnover. RESULTS: Transdermal application of testosterone for 30 days at a dose that affects penile growth increased mean (+/-SD) plasma testosterone concentrations from 7.5+/-5.1 to 31.0+/-8.2 ng/dL (pre- vs. post-treatment, respectively; P<0.01). This was associated with a slight but statistically significant elevation of IGF-I concentrations (117.2+/-76.9 vs. 154.4+/-81.5 ng/mL; P<0.05). No significant change in osteocalcin levels was found. CONCLUSIONS: When using testosterone ointment as a treatment for microphallus, it should be borne in mind that this application has systemic effects.

Administration, Cutaneous↗
PubMed2001

Magnetic resonance cholangiopancreatography in assessing the cause of acute pancreatitis in children.

Magnetic resonance cholangiopancreatography (MRCP) is a new noninvasive method of obtaining images of the pancreaticobiliary tract. Recent advances in MR technology and image quality have made it easy to diagnose structural abnormalities of the pancreaticobiliary tract (SAPBT) in children. To examine the usefulness of MRCP in assessing the cause of acute pancreatitis in children, we performed MRCP in 16 patients with acute pancreatitis. The study population was divided into two groups according to the cause of acute pancreatitis as follows: group 1 consisted of seven patients sonographically diagnosed with choledochal cysts; and group 2 consisted of nine patients with no obvious cause of acute pancreatitis. Non-breath-hold MRCP using the half-Fourier, single-shot, fast spin-echo imaging method was performed within 7 days after the onset of pancreatitis. Abnormal union of the pancreaticobiliary junction was detected in six of seven group 1 patients and in one of nine group 2 patients. Pancreatic divisum was detected in one patient of group 1, but could not be confirmed in one patient of group 2. Dilatation of the main pancreatic duct was detected in one patient of group 1 and in three patients of group 2. Our results suggest that MRCP is a useful, noninvasive method of identifying and ruling out SAPBT as a cause of acute pancreatitis in children with early-stage pancreatitis.

Acute Disease↗
PubMed2001

Helicobacter pylori intrafamilial infections: change in source of infection of a child from father to mother after eradication therapy.

Biopsy specimens of the antrum and corpus were obtained from four Helicobacter pylori-infected members of a family and from the same boy (son 1) in whom the infection reappeared after simultaneous successful eradication treatment of three family members, excluding the mother. A total of 18 to 60 H. pylori isolates were obtained from each specimen and subjected to rRNA gene restriction pattern analysis. The father's isolates and the initial isolates from son 1 showed the same HindIII type, which was divided into three HaeIII subtypes. Isolates from the mother and a brother (son 2) and posttreatment isolates from son 1 showed a distinct HindIII type (with one minor subtype), which was divided into six HaeIII subtypes. All subtypes of the initial isolates from son 1 were present in the father's isolates, and all subtypes of the posttreatment isolates from son 1 were present in the mother's isolates but not in son 2's. Electron microscopic analysis of the biopsy specimens demonstrated extremely high levels of H. pylori colonization in the father's gastric mucosa. H. pylori adherence with a ruffle formation was also demonstrated. The findings suggest that son 1 was infected initially with the H. pylori strain of the father and son 2 was infected with the H. pylori strain of the mother and that after eradication therapy son 1 was reinfected with the H. pylori strain of the mother, who did not undergo eradication therapy.

Adult↗
PubMed2001

Apoptosis of renal tubular cells in Shiga-toxin-mediated hemolytic uremic syndrome.

In order to clarify the mechanism of unusual renal tubular dysfunction seen in a child with Shiga toxin (Stx)-mediated hemolytic uremic syndrome (HUS), we studied the renal biopsy specimens for Stx binding and apoptosis of renal tubular cells. A 7-year-old boy with Stx-2-mediated HUS demonstrated extensive renal tubular damage characterized by nonoliguric acute renal failure, increased urinary tubular enzymes and defective urine-concentrating capacity. His renal biopsy specimens were analyzed for Stx binding and apoptotic cell death. Seven kidney tissue specimens obtained from patients without HUS served as controls. Detection of Stx binding to renal sections and apoptotic cells were performed using mouse monoclonal anti-Stx 2 antibody and the TUNEL method, respectively. Positive staining was observed predominantly in renal tubular cells, while the 7 kidney tissue specimens from control patients did not show positive staining. To the best of our knowledge, this is the first case to show Stx binding and apoptotic cell death in renal tubules on biopsy specimens obtained from a child with Stx-mediated HUS. In conclusion, this case suggests that vascular endothelial cells are not the sole nor the consistent target for Stx-mediated cell injury and that significant renal tubular damage other than glomerular damage might occur in some children with Stx-mediated HUS.

Apoptosis↗
PubMed2001

Effects of n-3 polyunsaturated fatty acids and vitamin E on colonic mucosal leukotriene generation, lipid peroxidation, and microcirculation in rats with experimental colitis.

AIMS: We investigated the effect of n-3 polyunsaturated fatty acids (PUFAs) on mucosal levels of leukotrienes (LTs) and lipid peroxide (LPO), and on mucosal microcirculation, in rats with experimental colitis induced by dextran sulfate sodium (DSS). METHODS: We fed Wistar rats a perilla oil-enriched diet containing alpha-linolenic acid (63.2% of total fatty acids) with various doses of vitamin E for 4 weeks, with 4% DSS added to the drinking water during the last week. Control rats were fed a diet produced from soybean oil containing alpha-linolenic acid (5.1% of total fatty acids). Colonic mucosal blood flow was measured with a laser Doppler flowmeter. RESULTS: The mucosal level of arachidonic acid was significantly lower and that of eicosapentaenoic acid was significantly higher in the experimental group. The mucosal level of LPO in the experimental group fed a trace or ordinary dose of vitamin E was significantly higher than that of the controls. The production of LTB(4) and LTC(4) from the colonic mucosa in the experimental group was significantly lower than that in controls. However, only the experimental group fed a vitamin E dose 4-fold higher than that given to the controls showed a significant increase in mucosal blood flow. CONCLUSION: These results suggest that n-3 PUFAs increase mucosal blood flow by inhibiting LT production when there is sufficient vitamin E to inhibit lipid peroxidation in rats with experimental colitis.

Administration, Oral↗
PubMed2001

[Bone mineral density of eating disorder].

Osteoporosis recently has been added to growing list of medical complications assisted with eating disorder in particular Anorexia nervosa. These often occur early in the course of anorexia in adolescent girls, presumably because this disorder not only interrupts the normal rapid bone accretion characteristic of adolescences, but also accelerate bone loss. The pathogenesis of osteoporosis in AN has not been completely characterized. While low body mass and amenorrhea are clearly important variables, other focters also may be involved. Some possible contributing factors in patients with AN include low Ca intake, increased glucocorticoids, insulin growth factor 1 deficiency. Simple weight gain needs to be part of the treatment, although it and exercise remain of unproven benefit for osteoporosis in patients with AN. But some studies have found that the clinical course of osteoporosis is not reversed simply with weight restoration. Long term studies are needed to answer the question of whether osteoporosis assisted with eating disorder is reversible.

Anorexia Nervosa↗
PubMed2001

Long chain polyunsaturated fatty acids (LC-PUFA) and perinatal development.

UNLABELLED: This paper reports on the conclusions of a workshop on the role of long chain polyunsaturated fatty acids (LC-PUFA) in maternal and child health. The attending investigators involved in the majority of randomized trials examining LC-PUFA status and functional outcomes summarize the current knowledge in the field and make recommendations for dietary practice. Only studies published in full or in abstract form were used as our working knowledge base. CONCLUSIONS: For healthy infants we recommend and strongly support breastfeeding as the preferred method of feeding, which supplies preformed LC-PUFA. Infant formulas for term infants should contain at least 0.2% of total fatty acids as docosahexaenoic acid (DHA) and 0.35% as arachidonic acid (AA). Since preterm infants are born with much less total body DHA and AA, we suggest that preterm infant formulas should include at least 0.35% DHA and 0.4% AA. Higher levels might confer additional benefits and should be further investigated because optimal dietary intakes for term and preterm infants remain to be defined. For pregnant and lactating women we consider it premature to recommend specific LC-PUFA intakes. However, it seems prudent for pregnant and lactating women to include some food sources of DHA in their diet in view of their assumed increase in LC-PUFA demand and the relationship between maternal and foetal DHA status.

Animals↗
PubMed2000

cDNA cloning and chromosomal mapping of the gene encoding adenylate kinase 2 from Drosophila melanogaster.

As a step toward understanding of the role of adenylate kinase (AK) in energy metabolism, we analyzed this enzyme in Drosophila melanogaster. The enzyme activities of all three AK isozymes were determined in cell-free extracts of flies, and their proteins were detected by Western blot analysis using polyclonal antibodies against the mammalian isozymes. A cDNA encoding adenylate kinase was isolated from D. melanogaster cDNA library. The cDNA encodes a 240-amino acid protein, which shows high similarity to bovine, human and rat AK2, and hence was named DAK2. Preliminary subcellular fractionation analysis indicated that DAK2 is localized in both cytoplasm and mitochondria. In situ hybridization to salivary gland polytene chromosomes revealed that the Dak2 gene is located at 60B on the right arm of the second chromosome.

Adenylate Kinase↗
PubMed2000

Non-lupus nephropathy associated with antiphospholipid antibodies.

Renal biopsy was performed in a 12-year-old girl with hematuria and proteinuria which was first detected at the age of 7, and the findings were the mesangial proliferative glomerulonephritis with IgG and C3 deposits. The routine blood examination for the biopsy disclosed the presence of the prolonged activated partial thromboplastin time and the biological false positive reaction in the syphilis test. These results led us to the further investigation, which revealed the presence of high titers of anticardiolipin antibodies. Since this girl presented no extra-renal symptoms of systemic lupus erythematosus (SLE) and had negative serologic tests for SLE, we hypothesize that her nephritis is closely related to antiphospholipid antibodies.

Antibodies, Antiphospholipid↗
PubMed2000

Xanthogranulomatous pyelonephritis in childhood: a rare but important clinical entity.

PURPOSE: Xanthogranulomatous pyelonephritis (XGPN) is extremely rare in children. The authors review their experience of this condition. METHODS: Medical records were investigated to conduct a retrospective study of 4 patients with XGPN (3 boys, 1 girl; age range, 2 months to 7 years) at the authors' institute over the past 14 years. RESULTS: Three of the 4 patients presented with fever of unknown origin and 1 with general fatigue. An abdominal mass was palpable in two cases at initial presentation. Although all patients had pyuria or hematuria, preoperative urine culture was positive in only 2 cases. Preoperative radiologic studies showed that 1 kidney was affected completely in 2 cases and affected partially in 2 cases. Preoperatively, the provisional diagnosis was XGPN in 3 cases, and Wilms' tumor in 1 case. Total nephrectomy was performed in 3 cases and enucleation in 1 case. XGPN was confirmed in all cases by histopathologic studies, but the underlying disease could be identified only in 1 case (cystinuria). All patients did well postoperatively and have had no further health problems over a mean follow-up period of 4.8 years. CONCLUSIONS: XGPN should be considered when there is a history of recurrent or therapy-resistant pyelonephritis. Preoperative radiologic investigation is paramount for diagnosis, and nephrectomy is the treatment of choice, although partial resection or enucleation are adequate for partially affected kidneys.

Child↗