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S Suita

Publications and source records attributed to S Suita.

At least 55 records · Page 3Linked to original sources
PubMed2000

Genomic imprinting of insulin-like growth factor-2 in infant leukemia and childhood neuroblastoma.

BACKGROUND: Loss of imprinting (LOI) of insulin-like growth factor-2 (IGF-2) has been implicated in the pathogenesis of certain human cancers and tumor-predisposing overgrowth disorders, such as Beckwith-Wiedemann syndrome. In a previous study, the authors revealed that certain patients with childhood acute leukemia and neuroblastoma had had rapid somatic growth after birth, suggesting the involvement of growth factor(s) in tumorigenesis. In the current study, the authors examined whether relaxation of IGF-2 imprinting occurred in infant leukemia and childhood neuroblastoma. METHODS: The genomic DNA of infant leukemia, childhood neuroblastoma, and control individuals was amplified by polymerase chain reaction (PCR). Patients who had heterozygous genotype were selected as informative cases using Apa I polymorphism in exon 9 of the IGF-2 gene. Total RNA was isolated from informative cases, followed by cDNA synthesis. cDNA was amplified by PCR, and direct sequence was performed for determining allele specific transcription. RESULTS: Twenty of 22 infant leukemia blasts and all of 16 neuroblastoma cells showed normal monoallelic expression of IGF-2 as well as 23 controls. The height and weight of two acute lymphoblastic leukemia patients with LOI were within normal ranges for Japanese children. CONCLUSIONS: The current study revealed that the imprinting status of IGF-2 was generally maintained in infant leukemia and confirmed that it was maintained in childhood neuroblastoma. The results suggest that LOI of IGF-2 does not play a major role in the carcinogenesis of these diseases or in rapid physical growth of the patients.

Female↗
PubMed2000

The formation of the chick ileal muscle layers as revealed by alpha-smooth muscle actin immunohistochemistry.

The genesis of intestinal smooth muscle layers was immunohistochemically investigated by use of an antibody to alpha-smooth muscle actin (alpha-SMA) in the developing chick ileum. Myoblast cells positive for alpha-SMA were already found in the presumptive circular muscle layer on E 8.5. On E 11.5 radially oriented muscle fibers were protruded from the outermost layer of the developing circular musculature and then formed a tuft-like aggregates. These radial muscle bundles were bent into an L-shape. The long distal extension of muscle bundles run parallel to the long axis of the ileal loop and developed into the longitudinal muscle layer. The obliquely oriented muscle fibers, locating at the intermuscular space of the muscularis propria, probably are to be considered a remnant of the short extension of radial muscle bundles. The muscularis mucosae was formed by the processes equivalent to the genesis of longitudinal muscle layer. On E 14.5 centripetally oriented muscle fibers emerged from the innermost layer of circular musculature. The long distal extension of centripetal fibers lay along the inner surface of developing circular musculature. On E 19.5 the longitudinal muscle layer of the muscularis mucosae was newly formed by separating from the circular musculature. The villous myoblast cells initially developed from the innermost layer of the muscularis mucosae on E 18.5, and were widely distributed in the lamina propria mucosae on E 20.5. Temporal and chronological pattern in expression of alpha-SMA was observed during the development of the chick intestinal smooth muscle. By E 14.5 the entire layer of the muscularis propria was intensely immunostained for alpha-SMA, but from E 15.5 onward the staining intensity gradually began to decrease from the outer half of the circular musculature. Finally, the immunoreactivity was localized in the inner layer of circular muscle and the longitudinal muscle layer. A possible functional role of this inner layer of circular muscle is discussed.

Actins↗
PubMed2000

Comparative studies of fertility and histologic development of contralateral scrotal testes in two rat models of unilateral cryptorchidism.

Fertility and the development of the contralateral scrotal testis in patients with unilateral cryptorchidism (UCO) remain controversial. This study investigated these controversies in two different UCO rat models using 43 Wistar King A rats. The animals were divided into three groups: I: an endocrinologic model of UCO was obtained by injecting pregnant dams with flutamide 100 mg/kg per day on days 15-17 of gestation (n = 12); II (n = 21): a mechanical model of UCO was obtained by extra-abdominal fixation of the gubernaculum in the neonatal period, III (n = 10): non-treated rats were used as controls. At the age of 90 days, 5 rats from each group were segregated into individual cages and housed with two virgin adult females for 2 weeks. The occurrence of pregnancy and litter sizes were counted in order to study fertility. All the animals were then weighed and killed. The occurrence of testicular descent, growth of the external genitalia, and epididymal development were examined. Morphologic and histologic evaluations were performed in the cryptorchid and contralateral testes. In the endocrinologic model (group I) the 10 female rats failed to show any offspring (0%), while in the mechanical model (group II) 9 out of 10 rats had offspring (90%, P < 0.001); 10 out of 10 control rats showed offspring. All of the rats in groups I and II had UCO, and the undescended testes were located in the superficial inguinal position, while the contralateral and control testes descended into the scrotum. Hypospadias and a small epididymis were frequently noted in the flutamide-treated rats. Testicular weight, seminiferous tubular diameter, and spermatogenesis were all significantly reduced in the undescended testes (UDT) compared to the contralateral and control testes. Moreover, the development of the contralateral testis was inhibited in group I compared to groups II and III. Our observations showed that short-term exposure to flutamide in utero induced significantly reduced fertility and degenerated contralateral scrotal testes in UCO rats compared to mechanically-induced UCO rats by early adulthood. It is suggested that fertility potential and testicular development in unilateral UDT may be partially due to the factors that induce testicular maldescent, especially in cases due to intrauterine hormonal abnormalities. These cases may show inhibited fertility and testicular development even after orchiopexy.

Androgen Antagonists↗
PubMed2000

The efficacy of predeposited autologous blood transfusions in general pediatric surgery.

Allogeneic blood transfusions are associated with a risk of infection, immunological reactions, immunosuppression, and the induction of antibodies in blood cells. We report our results of giving predeposited autologous blood transfusions (PABT) to children when it was anticipated that transfusions would be required for an elective operation. Autologous blood was collected for deposit from 16 patients ranging in age from 1 to 11 years old (mean 5.6 years old, mode 4 years old), and weighing from 9.7 to 42 kg (mean 20.8kg). They included 12 patients with pectus excavatum (funnel chest) and 4 patients with choledochal cyst (CBD). Blood was collected once from 2 patients and twice from the other 14 patients, then centrifuged and stored in a freezer at -80 degrees C. Between 7 and 14 ml/kg was collected at one time, the total mean volume of predeposited blood being 21.0 +/- 3.3 ml/kg for the children operated on for funnel chest, and 16.2 +/- 4.5 ml/ kg for those operated on for CBD. None of the patients required allogeneic transfusions and no complications occurred. PABT was found to be a safe and effective means for elective general pediatric surgical procedures for avoidance of allogeneic blood transfusion.

Blood Transfusion, Autologous↗
PubMed2000

Alteration of the [Ca(2+)](i)-force relationship during the vasorelaxation induced by a Ca(2+) channel blocker SR33805 in the porcine coronary artery.

The mechanism of vasorelaxation induced by SR33805 was investigated by simultaneously monitoring the cytosolic Ca(2+) concentration ([Ca(2+)](i)) and force, and by determining level of myosin light chain (MLC) phosphorylation in the medial strip of the porcine coronary artery. SR33805 inhibited the sustained increases in [Ca(2+)](i) and force (IC(50); 3.2+/-1.0 and 49.4+/-27.5 nM, respectively) induced by 118 mM K(+)-depolarization. There was about a 10 fold difference in the inhibitory potency between [Ca(2+)](i) and force. SR33805 completely inhibited the [Ca(2+)](i) elevation induced by a thromboxane A(2) analogue, U46619 and histamine, at concentrations (1 microM) higher than those required for the complete inhibition of K(+)-depolarization induced [Ca(2+)](i) elevation. SR33805 had no effect on the [Ca(2+)](i) elevation induced by histamine or caffeine in the absence of extracellular Ca(2+). SR33805 caused a leftward shift of the [Ca(2+)](i)-force relationship of the contraction induced by cumulative application of extracellular Ca(2+) during 118 mM K(+)-depolarization. The relationship between [Ca(2+)](i) and MLC phosphorylation also shifted to the left by SR33805, while the relationship between MLC phosphorylation and force remained unaffected. In conclusion, SR33805 caused an apparent leftward shift of the [Ca(2+)](i)-force relationship, accompanied by a greater degree of MLC phosphorylation for a given level of [Ca(2+)](i). The mechanism of this leftward shift, however, still remains to be elucidated.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2000

Time-specific effects of mono-n-butyl phthalate on the transabdominal descent of the testis in rat fetuses.

OBJECTIVE: To determine the time-specific effects of mono-n-butyl phthalate (MBP) on the transabdominal migration of the testis in fetal rats. Materials and methods Three groups of pregnant rats were administered MBP by stomach-tube feeding when the fetus was at 7-10 days of gestation in group 1, 11-14 days in group 2, and 15-18 days in group 3; controls (group 4) were given vehicle only from 7-18 days. At 20 days of gestation the fetuses were obtained by Caesarean section, and the position of the testes, the development of the gubernaculum, cranial suspensory ligament and the epididymis were examined. RESULTS: The timed intervals of MBP administration showed that the maximum inhibition of transabdominal testicular descent was at 15-18 days of gestation. There was an elongated gubernaculum and hypertrophic cranial suspensory ligament in the MBP-treated rat fetuses. Furthermore, the epididymis showed a few small ducti deferentia, although there were no remarkable changes in either the Sertoli and Leydig cells in these testes. The mean (SEM) content of testicular testosterone was significantly less (P < 0.001) in the MBP-treated rats, at 50.9 (3.8) pg/testis, than in the controls, at 676 (33.3) pg/testis. CONCLUSIONS: These findings indicate that a brief exposure to MBP during fetal development can inhibit the transabdominal migration of the testis and reduce testosterone content in rats, although the relationship between migration and the testicular testosterone content remains unknown.

Animals↗
PubMed2000

Clinical implications of minimal disease in the bone marrow and peripheral blood in neuroblastoma.

PURPOSE: In patients with neuroblastoma (NB), minimal disease (MD) in bone marrow (BM) and peripheral blood (PB) is thought to play an important role in metastasis. The current study was designed to evaluate the clinical implications of the detection of MD in NB at the initial diagnosis. METHODS: Expression of the neuroendocrine protein gene product 9.5 (PGP9.5) and tyrosine hydroxylase (TH) mRNA in BM and PB obtained from 18 patients with NB was investigated by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: MD was detected in the BM obtained from 4 of 14 localized NB patients and also in the PB from 2. However, it was found also in both the BM and PB obtained from all 4 patients with metastatic NB. Two of the 4 MD-positive patients with localized NB had metastatic recurrence after a complete tumor excision. They also had unfavorable biological prognostic factors compared with the other 2 who did not have recurrent disease. CONCLUSION: MD detected by RT-PCR in the BM and the PB of patients with NB thus suggests a risk for metastatic disease, which in association with other unfavorable biological features may indicate a poor prognosis.

Adolescent↗
PubMed2000

Improved survival for patients with advanced neuroblastoma after high-dose combined chemotherapy based in part on N-myc amplification.

BACKGROUND/PURPOSE: In spite of many different kinds of chemotherapy for neuroblastoma, the prognosis for advanced neuroblastoma remains unsatisfactory. In particular, the outcome of advanced neuroblastoma with high copies of the N-myc gene tend to be poor. Therefore, the new high-dosage combined chemotherapy regimens for advanced neuroblastoma based in part on the N-myc amplification status has been utilized in the Kyushu area of Japan since 1991. This study aims to investigate whether these new regimens based in part on N-myc amplification have improved the survival rate of stage III and stage IV patients in comparison with the old regimens. METHODS: Between 1983 and 1995, 77 patients over 1 year of age and with stage III or IV neuroblastoma were registered in the Kyushu Area. Between 1983 and 1990, 49 patients received 1 of 2 combined chemotherapy regimens consisting of cyclophosphamide, cisplatin plus VM-26, and Adriamycin plus DTIC. Since 1991, two new regimens (New A1 and A3) have been administered based on the N-myc amplification status in a total of 28 patients. The New A1 regimen, which consists of cyclophosphamide, cisplatin, Adriamycin, and VP-16 has been administered in cases of less than 10 copies of N-myc, whereas the A3 regimen, consisting of a higher dose of cyclophosphamide, cisplatin, Adriamycin, and VP-16, has been administered in cases of more than 10 copies of N-myc. The survival rate was then compared between the old regimens and the new regimens. RESULTS: The 3-year survival rate (61.5%) for patients treated by the new regimens was significantly higher than that (32.7%) for patients treated by the old regimens (P <.01). Regarding the 24 cases of more than 10 copies of N-myc, the 3-year survival rate (35.9%) of the 13 patients treated by the A3 regimen was higher than that (0%) of the 11 patients treated by the old regimens (P <.05). However, in the 19 stage IV patients treated by the new regimens, the 3-year survival rate (11.1%) of the 9 cases of more than 10 copies was significantly lower than that (77.8%) of the 10 cases of less than 10 copies of N-myc (P <.01). CONCLUSIONS: These results suggest that high-dose combined chemotherapy based in part on the N-myc amplification status significantly improved the prognosis of patients with advanced neuroblastoma. However, stage IV patients with N-myc amplification still require a more effective treatment modality.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

The validity of bioelectrical impedance phase angle for nutritional assessment in children.

BACKGROUND/PURPOSE: Bioelectrical impedance analysis (BIA) is a quick and noninvasive method for estimating body composition. Many prediction equations have been reported recently using bioelectrical impedance to calculate fat free mass (FFM) and fat mass (FM). These equations are based on the assumption that the composition and density of FFM are stable. In children, the composition and density of FFM vary according to age and clinical state, so the use of these equations is limited. However, phase angle is directly determined from resistance (Rz) and reactance (Xc) without equations and reflects body cell mass. The authors, therefore, investigated the validity of phase angle for nutritional assessment in children. METHODS: Bioelectrical impedance analysis and anthropometric measurements were performed in 81 patients, including 71 well-nourished and 10 malnourished children. RESULTS: Phase angle correlated with body weight (R = 0.818) and arm muscle circumference (r = 0.901) in well-nourished children. Malnourished patients showed lower phase angle than that of well-nourished children. CONCLUSION: Bioelectrical impedance phase angle is a useful parameter for nutritional assessment in children.

Body Composition↗
PubMed2000

The characteristics of mediastinal neuroblastoma.

The prognosis of mediastinal neuroblastoma has been reported to be better than for other neuroblastomas. The reason for this is however not clear. Furthermore, a comparison between mediastinal neuroblastoma and the other neuroblastomas has been rarely reported so far. In this study, the characteristics of mediastinal neuroblastoma (84 cases) are investigated and compared with those of other neuroblastomas (440 cases). Regarding clinical factors, the age distribution and the rate of cases detected at mass screening were similar in both groups. According to Evan's staging system, the rates of early stage (I, II) were 62% in the mediastinal neuroblastoma and 38% in the other neuroblastomas (p<0.001). Regarding the biological prognostic factors, a favorable histology based on Shimada's classification was found in 100% (35/35) of the mediastinal neuroblastoma cases and in 85% (112/132) of the other neuroblastoma cases (p<0.05). With regard to N-myc amplification, all of the examined 42 cases in mediastinal neuroblastoma had a N-copy number of less than 10 copies, while 32 of the examined 263 cases (12%) in the other neuroblastomas had an amplification of N-myc of more than 10 copies (p<0.05). The 5-year survival rates were 78% in the mediastinal neuroblastoma and 59% in the other neuroblastomas, respectively. Of the cases who underwent an incomplete resection of primary tumors in localized neuroblastoma, the 5-year survival rate of the mediastinal neuroblastoma cases was significantly more favorable than that of the other neuroblastomas. The majority of mediastinal neuroblastoma cases showed an early stage and favorable prognostic factors. It is likely that the clinical and biological prognostic factors of the tumor are therefore more closely correlated with the outcome of mediastinal neuroblastoma rather than the degree of the surgical resection. Regarding the treatment for mediastinal neuroblastoma, it is most important to evaluate the biology of the tumor after surgical resection.

Child, Preschool↗
PubMed2000

Changing profile of abdominal wall defects in Japan: results of a national survey.

BACKGROUND/PURPOSE: The incidence of gastroschisis has increased over the past 3 decades in a number of countries. To elucidate the Japanese status of anterior abdominal wall defects, the Japanese Society of Pediatric Surgeons conducted a national survey in Japan. METHODS: Information was obtained by sending out a questionnaire to 192 University Hospitals, Children's hospitals, and general hospitals that each had more than 200 beds. The characteristics of the patients including the birth date, birth weight, gestations, rate of associated anomalies, rate of antenatal diagnosis and prognosis, maternal age, gravidity, history of smoking, and drug use were analyzed. RESULTS: The authors obtained answers from 149 institutions, including 1,785 cases of omphalocele and 970 cases of gastroschisis, which were treated between 1975 to 1997. There was a significant increase in the incidence of gastroschisis, from 0.131 in 1975 to 1980, 0.269 in 1981 to 1985, 0.337 in 1986 to 1990, 0.461 in 1991 to 1995 to 0.467 per 10,000 births in 1996 to 1997. The incidence of omphalocele was 0.322 in 1975 to 1980, 0.567 in 1981 to 1985, 0.657 in 1986 to 1990, 0.741 in 1991 to 1995 to 0.626 per 10,000 births in 1996 to 1997, respectively. In the omphalocele group, 43.1% of the mothers were between 25 to 29 years of age, whereas in the gastroschisis group 42.6% of the mothers were 20 to 24 years of age. In the gastroschisis group, the number of primipara mothers was larger than that of multipara mothers. In the omphalocele group, approximately 10% of the mothers smoked during each period, whereas in the gastroschisis group, the percentage of smoking mothers increased chronologically from 12.9% in 1981 to 1985, 18.7% in 1986 to 1990, 23.5% in 1991 to 1995 and 29.3% in 1996 to 1997. A history of drug use by the mother was approximately 10% for both the omphalocele and gastroschisis groups. In the omphalocele group, 55.9% had associated anomalies against 21.8% in the gastroschisis group. Approximately 10% in the omphalocele group and less than 3% in the gastroschisis group showed chromosomal abnormalities. From 1986, a significant number of cases detected antenatally has been observed. CONCLUSIONS: There have been substantial changes in the incidence of anterior abdominal wall defects, particularly regarding gastroschisis in Japan. The reasons for such changes are most likely multifactorial, further epidemiological monitoring is thus called for.

Abnormalities, Multiple↗
PubMed2000

Analysis of the prognostic factors relating to better clinical outcome in ganglioneuroblastoma.

PURPOSE: To elucidate the precise reason for the better prognosis in ganglioneuroblastoma (GNB) than in neuroblastoma (NB), the prognostic factors (age at diagnosis, stage at diagnosis, primary site, N-myc amplification, Shimada classification, and ploidy) were analyzed. METHODS: A retrospective analysis of the 57 neuroblastoma cases (20 GNB cases and 37 NB cases), that had not been detected by mass screening over the past 19 years at the authors' institute, was carried out. RESULTS: A Kaplan-Meier analysis of the 5-year survival rates were 67.2% and 35.1% in cases of GNB and NB, respectively, and these rates were significantly higher in GNB (logrank test; P = .04631). No significant differences were seen between GNB and NB regarding the rate in patients 1 year of age or older (95.0% v 78.4%; P = .1005), the rate of advanced cases (60.0% v 78.4%, P = .1406), the rate of an unfavorable histology (Shimada classification, 54.5% v 68.4%, P = .4473), or the diploid pattern rate (75.0% v 76.9%, P = .9200). However, N-myc amplification was found exclusively in NB (amplified cases per examined cases; 15/31), and all cases with N-myc amplification died. When the 5-year survival rate was evaluated in the patient without N-myc amplification between GNB and NB, no significant difference was observed (logrank test; P = .8568). CONCLUSION: The better prognosis in patients with GNB was thus thought to be exclusively related to an absence of N-myc amplification.

Ganglioneuroblastoma↗