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K Tokiwa

Publications and source records attributed to K Tokiwa.

At least 37 records · Page 2Linked to original sources
PubMed1997

Results of a modified Duhamel Operation for Hirschsprung's disease using the GIA stapler.

Thirty-six patients with Hirschsprung's disease underwent surgery using modified Duhamel operation with the GIA (gastrointestinal autosuture) stapler over a 12-year period at our institution. We now present our experience from the perspective of postoperative complications and anorectal function. Postoperative complications included minimal anal bleeding due to the GIA stapler in 2 patients, and mild enterocolitis in 6 patients. Severe complications such as anastomotic leakage or stricture were not observed in our series. Overall, postoperative anorectal function was good in patients without Down's syndrome or cerebral palsy. Follow-up of our patients showed that a good quality of life was achieved during childhood. We conclude, therefore, that the modified Duhamel operation, with the use of the GIA stapler, is a safe and easy procedure for correction of Hirschsprung's disease.

Child, Preschool↗
PubMed1996

OK-432 therapy for lymphangioma in children: why and how does it work?

Intralesional injection of OK-432 (lyophilized incubation mixture of group A Streptococcus pyogenes of human origin) is safe and effective therapy for lymphangioma. The authors evaluated the mechanism of this therapy in 6 patients who had cystic lymphangioma. The intracystic fluid of the cystic lymphangioma was aspirated before and after (on days 1 and 4) the OK-432 therapy. Changes in cell populations and cytokine productions in each aspirated fluid were analyzed. White blood cells in the intracystic fluid increased markedly in number. Before OK-432 therapy, 96% of the intracystic white blood cells were lymphocytes, and the remaining were neutrophils and macrophages. On day 1, the percentages of neutrophils and macrophages increased to 72% and 21%, respectively. On day 4, the percentage of lymphocytes increased to 72%. Flow cytometry analysis using monoclonal antibodies showed that the number of natural killer cells (CD56+) and T cells (CD3+) had increased. The activity of cytotoxic tumor necrosis factor (TNF) and interleukin-6 increased immediately after OK-432 injection and remained high in titer until day 4. These findings suggest that the white blood cells induced and activated by OK-432, and the cytokines (including TNF) produced by these cells increased the endothelial permeability, and thus the accelerated lymph drainage and increased lymph flow let to shrinkage of the cystic spaces.

Adult↗
PubMed1996

Early mucosal changes of the gallbladder in patients with anomalous arrangement of the pancreaticobiliary duct.

BACKGROUND & AIMS: Anomalous arrangement of the pancreaticobiliary duct (AAPBD) is frequently associated with gallbladder cancer. The aim of this study was to characterize the early epithelial changes of the gallbladder that might be associated with carcinogenesis in patients with AAPBD. METHODS: Routinely fixed tissue specimens obtained from pediatric patients with AAPBD and control patients were examined histologically with H&E, periodic acid-Schiff, and argyrophilic nucleolar organizer region (AgNOR) staining. RESULTS: Epithelial hyperplasia was frequently observed in the gallbladder of patients with AAPBD but not in patients without this anomaly. The incidence of epithelial hyperplasia was significantly higher in the gallbladder of patients in whom the major pancreatic duct joined the common bile duct (P-C type) than in patients in whom the common bile duct joined the pancreatic duct (C-P type). The mean AgNOR number in the gallbladder mucosa was significantly higher in patients with AAPBD than in patients without AAPBD. Patients with C-P type AAPBD had a significantly higher mean AgNOR number of the gallbladder mucosa than patients with C-P type AAPBD. CONCLUSIONS: Patients with AAPBD, especially those with the P-C type anomaly, have increased cellular proliferative activity of the gallbladder mucosa in early childhood.

Bile Ducts↗
PubMed1996

Surgical reconstruction of a high cloacal anomaly with two short vaginas.

We treated a patient with a complex cloacal malformation: a high confluence cloaca and 2 separate short vaginas. At the age of 1 year and 2 months the rectocloacal fistula was closed because of frequent urinary infections, and the vaginas were separated from the wide urogenital sinus and anastomosed to the lower colon. At the age of 2 years and 4 months the lower colon, which had been anastomosed with the 2 vaginas, was pulled down to the perineum to serve as a lower vagina, and the sigmoid colon was pulled through to form a neorectum. She is now 7 years old and goes to school without problems of bowel function or urinary function except that catheterization is done twice a day.

Anus, Imperforate↗
PubMed1996

Impaired autoregulation in an experimental model of chronic cerebral hypoperfusion in rats.

BACKGROUND AND PURPOSE: To verify the hypothesis that impaired autoregulation may contribute to cerebral swelling or hemorrhage after a sudden recovery of perfusion pressure, we studied the chronic effects of cerebral hypoperfusion on the autoregulatory responses of the pial arterioles in situ. METHODS: Eight to 12 weeks after a carotid-jugular fistula was created in rats, experiments were performed under alpha-chloralose and urethane anesthesia. Regional cerebral blood flow (rCBF) was determined by the hydrogen clearance method, and carotid pressure was measured. Using a closed cranial window, we determined the autoregulatory responses of the arterioles (30 to 50 microns) to both hypertension induced by norepinephrine and sudden fistula closure at various mean arterial pressures (MAPs). RESULTS: rCBF on the fistula side was reduced by 27%. Carotid pressure was significantly lower than normal but was immediately increased by fistula closure. The pial arterioles showed marked elongation and enlargement. During induced hypertension, the arterioles in the fistula group started to dilate at an MAP lower than that of the control group (130 versus 180 mm Hg, respectively). The arterioles constricted when the fistula was occluded at normal MAP. However, when the fistula was occluded at an MAP higher than 130 mm Hg, the vessels dilated. CONCLUSIONS: It was demonstrated that (1) chronic hypoperfusion induced impairment of the upper limit of autoregulation and (2) sudden fistula closure under hypertensive conditions caused vasodilation of the arterioles. These findings suggest that rapid restoration of perfusion pressure is possibly followed by a pressure breakthrough phenomenon in a chronically hypoperfused cerebrovasculature.

Animals↗
PubMed1995

Intestinal obstruction in an infant due to magnet ingestion.

A case of intestinal obstruction in an infant due to magnet ingestion is reported. The 17-month-old female swallowed seven small magnets, and developed an acute intestinal obstruction. At laparotomy, a fistula between the jejunum and the ileum which contained the seven magnets was found and resected. The patient's postoperative recovery was uneventful. Accidental magnet ingestion mandates careful observation for the development of intestinal obstruction.

Acute Disease↗
PubMed1995

The effects of a carotid-jugular fistula on cerebral blood flow in the cat: an experimental study in the chronic period.

The purpose of the present study was to investigate the effects of feline carotid-jugular fistula (Spetzler's model) on cerebral blood flow at 8 weeks after creation of the fistula. Using laser-Doppler flowmetry, cortical cerebral blood flow (CBF) on the fistula side was measured in 10 cats, Occlusion of the fistula showed no cortical CBF changes in 6 animals, but transient increases in 4. CO2 reactivity in the closed fistula was preserved. No neurological or histological abnormalities were recognized. These findings suggested that cerebral hemodynamic changes due to Spetzler's CJ fistula model are minimal even in the chronic period after fistulization. Therefore, creation of another experimental arterio-venous fistula model is mandatory for the investigation of hemodynamic changes following resection of a cerebral arteriovenous malformation.

Animals↗
PubMed1994

The effects on cellular functions of bile acid and trypsin in stagnant bile juice in anomalous arrangement of the pancreaticobiliary duct.

To examine the reasons for the high frequency of biliary tract carcinogenesis in individuals with anomalous arrangement of the pancreaticobiliary duct (AAPBD), we investigated the effects on cellular functions of bile acid and trypsin, which are possible risk factors for carcinogenesis found in stagnant bile juice, using a chick embryo fibroblast culture system. Bile acid was found to increase PGE2 synthesis which has been shown to be increased in premalignant lesions, but to suppress the incorporation of [3H]-labelled TdR into DNA. On the other hand, trypsin increased the incorporation of [3H]TdR into DNA, but did not increase PGE2 synthesis. These results suggest that both the bile acid and trypsin present in the stagnant bile juice in AAPBD act to stimulate cell proliferation, but that their mechanisms of action on cell growth differ. Therefore, the combination of these effects of different types of tumor promoters in the stagnant bile juice in AAPBD may account for the high incidence of carcinogenesis.

Animals↗
PubMed1994

Increased numbers of argyrophilic nucleolar organizer regions between primary and metastatic sites predict tumor progression in stage IV and IV-S neuroblastoma.

BACKGROUND: A silver colloid technique to determine nucleolar organizer region (AgNOR) number was used to study the proliferative activity of Stage IV-S neuroblastoma in which a spontaneous tumor regression is often observed. METHODS: Primary regional lymph nodes and hepatic lesions from five children with Stage IV-S and five with Stage IV neuroblastoma were examined. RESULTS: Average AgNOR counts per tumor cell nucleus from all five children with Stage IV neuroblastoma were lowest in the primary lesions, intermediate in the metastatic regional lymph nodes, and highest in the distant metastases. However, in four Stage IV-S patients whose metastases later disappeared and showed no sign of recurrence, the average AgNOR number was similar in primary tumors and metastatic lesions. In the other patient with progressive metastases initially diagnosed as Stage IV-S, the data showed the same pattern as in Stage IV neuroblastoma. CONCLUSIONS: The unique AgNOR staining pattern may reflect the proliferative activity of Stage IV-S neuroblastoma. This method may provide further information to differentiate a subtype of metastatic neuroblastoma showing spontaneous tumor regression and/or favorable prognosis.

Adrenal Gland Neoplasms↗
PubMed1994

The effects of a carotid-jugular fistula on cerebral blood flow in the cat: an experimental study in the acute period.

The purpose of the present study is to investigate the effects of feline carotid-jugular (CJ) fistula (Spetzler's model) on cerebral blood flow (CBF) in the acute period after creation of the fistula. Using laser-Doppler flowmetry, cortical CBF was measured on the fistula side of 11 cats. Temporary occlusion and opening of the fistula led to an immediate increase and decrease, respectively, in cortical CBF. However, CBF returned to baseline within 1 minute, on average. CO2 reactivity in the closed fistula was preserved. It is suggested that cerebral hemodynamic changes due to Spetzler's CJ fistula model are minimal in the acute period after fistulization.

Acute Disease↗
PubMed1994

Draining vein pressure increases and hemorrhage in patients with arteriovenous malformation.

BACKGROUND: Recent radiological studies have shown that arteriovenous malformations with impaired venous drainage may be susceptible to hemorrhage. To evaluate this hypothesis using a hemodynamic approach, we measured intravascular pressure during surgery in three patients with arteriovenous malformation. SUMMARY OF REPORT: In three patients we measured intravascular pressures in the draining venous system and the feeding arteries simultaneously before removal of arteriovenous malformations with marked segmental stenotic or occlusive draining veins and evidence of hemorrhage. The draining vein pressures at prestenotic (or preocclusive) sites in the three patients were 38, 25, and 40 mm Hg, respectively, all significantly above the normal cortical venous pressure, whereas pressure measurements in poststenotic sites and the sagittal sinus pressure in the venous drainage system approached normal values. The feeding artery pressures in the patients were lower than normal cortical artery pressure because of the arteriovenous shunt. CONCLUSIONS: Intraoperative vascular pressure measurements support the hypothesis that arteriovenous malformations with impaired venous drainage may be associated with a local increase in venous pressure and thus may be susceptible to hemorrhage.

Adolescent↗
PubMed1994

An unruptured arteriovenous malformation with edema.

We report a case of unruptured arteriovenous malformation in which an extensive zone of increased signal intensity in the brain parenchyma adjacent to the nidus is demonstrated on T2-weighted MR. This area of perilesional hyperintense signal exerts a compressive effect, suggesting that it represents perilesional edema.

Brain Edema↗
PubMed1993

Lymphatic drainage of adrenal neuroblastoma.

The lymphatic drainage of adrenal neuroblastoma (NB) was investigated in 11 patients using intraoperative vital staining with carbon particle suspension. Carbon staining was most frequent in the nodes at the origin of the renal artery and next most frequent in the interaorticovenous nodes. The staining was characteristically noted in the paraaortic nodes and the nodes around the hemiazygos vein in cases of left adrenal NB, and in the paracaval nodes and the nodes around the azygos vein in cases of right adrenal NB. Histological evaluation confirmed a correlation with lymph node metastases and carbon staining. These findings suggest that the primary regional nodes of adrenal NB are the nodes at the origin of the renal artery, those around the hemiazygos vein in left adrenal NB, and those around the azygos vein in right adrenal NB. The secondary regional nodes are the interaorticovenous nodes, the paraaortic nodes in left adrenal NB, and the paracaval nodes in right adrenal NB. The topography of lymphatic drainage of adrenal NB should be considered in the management of this tumor.

Adrenal Gland Neoplasms↗
PubMed1993

Correlation between intravascular pressure and risk of hemorrhage due to arteriovenous malformations.

The correlation between intraoperative pressure levels measured in the feeding arteries and in the draining veins, and the risk of hemorrhage from arteriovenous malformations (AVMs) is discussed. Feeding artery pressure (FAP) was significantly higher in AVMs with hemorrhage (57 +/- 11 mmHg) than in AVMs without hemorrhage (38 +/- 4), and draining vein pressure (DVP) in the former (24 +/- 5) was significantly higher than that in the latter (13 +/- 5). FAP and DVP were inversely related to the number of draining veins and size of the AVMs. The present study suggests that a high FAP and a high DVP may contribute to the development of hemorrhage from AVMs, and supports previous reports that small AVMs and AVMs with only one draining vein are susceptible to hemorrhage.

Blood Pressure↗
PubMed1993

Biliary tract complications in patients with hypoganglionosis and chronic idiopathic intestinal pseudoobstruction syndrome.

The biliary tract system was studied in two patients with hypoganglionosis and chronic idiopathic intestinal pseudoobstruction syndrome (CIIPS) to evaluate manifestations of these diseases, especially as for underlying motility disorder. In a 3-year-old boy with hypoganglionosis, cholelithiasis was diagnosed and the gallbladder specimen showed a markedly hypoplastic neural plexus on histopathology as was found in his total alimentary tract. In a 2-year-old girl with CIIPS, echo-guided gallbladder wall motility testing demonstrated an impaired response to a ceruletide diethylamine stimulation. These clinical experiences in two patients suggest that these pathological entities may be frequently associated with biliary tract complications not only due to a consequence of total parenteral nutrition, but also due to a possible intrinsic involvement of biliary tract dysmotility.

Barium Sulfate↗
PubMed1993

Pulmonary hypertension as a fatal complication of extrahepatic portal hypertension.

Pulmonary hypertension is an uncommon complication of portal hypertension seen in cirrhotic as well as noncirrhotic patients. We report a 10-year-old girl who presented with extrahepatic portal hypertension and pulmonary hypertension in the absence of intrinsic liver disease. Further investigations revealed high serum concentrations of prostaglandin F2 alpha, thromboxane B2 in the inferior vena cava, and angiotensin I in the inferior vena cava and right ventricle. The increased levels of these vasoconstrictive substances strongly suggest that the possible mechanism for the pulmonary hypertension in such patients with extrahepatic portal hypertension include shunting of vasoactive agents from the splanchnic circulation to the pulmonary vascular bed.

Angiotensin I↗