Biomedical subjects

T Irie

Publications and source records attributed to T Irie.

304 records · Page 17Linked to original sources

PubMedDate not supplied

Morphologic study of intermediate filaments in rat hepatocytes.

Rat liver perfused with 0.5% Triton X-100 for 15 to 90 min followed by 1% sodium dodecyl sulfate for 30 min were studied by electron microscopy and polyacrylamide gel electrophoresis. After 15 min of perfusion, a rich network of intermediate filaments and microtubules was visualized in the cytoplasm of hepatocytes. Using stereopairs, branching was visualized. Connections of filaments were noted with nuclei, centrioles, microtubules, vesicles, and rough endoplasmic reticulum. The existence of connections supported the concept that intermediate filaments may function to integrate mechanically the cytoplasmic space as postulated by Lazarides.

Animals↗

PubMedDate not supplied

Mallory body formation runs parallel to gamma-glutamyl transferase induction in hepatocytes of griseofulvin-fed mice.

To evaluate whether Mallory bodies (MBs) are linked to the induction of the enzyme gamma-glutamyl transferase (GGT), mice were fed 2.5% griseofulvin (GF). The experimental and control mice livers were examined at four time periods, i.e., after 4 months' of GF feeding, 1 month after GF withdrawal and 13 days after GF refeeding, and at sacrifice after 4 months of GF withdrawal. The livers from mice continuously fed GF or control diet for 10 months were also examined. Tumors and nontumorous livers were examined histologically, histochemically, electron microscopically, and immunocytochemically. The tumors consisted of hepatomas and hyperplastic nodules. To localize MBs inside GGT-positive cells, a double-staining method was employed; GGT-positive cells were identified histochemically followed by staining for MBs using the unlabeled immunoperoxidase technique. The per cent area of the GGT-positive foci was closely correlated with the frequency of MBs observed in the course of a GF feeding and withdrawal. Almost all of the MBs were located in GGT-positive cells in both tumors and nontumor liver tissue. MBs and GGT positivity involved the same liver cells. They both were found in high frequency in tumors induced by GF. These results indicate that MB formation, like GGT induction, is a phenotypic change induced by GF. The coexistence of the two phenomenon in the same cell throughout all phases of tumor formation suggests that MBs may be related to the neoplastic process in the GF-fed mouse model.

Animals↗

PubMedDate not supplied

Cystic islet cell tumors: radiologic findings in three cases.

We report three cases of cystic islet cell tumors, two caused by gastrinomas and the other by an islet cell carcinoma. All three patients underwent computed tomography (CT) and angiography and two also had magnetic resonance (MR) imaging. Several common radiographic findings were present as follows: thickening of the cyst wall and irregularity of the inner surface on postcontrast CT and MR images, neovascularity and a densely staining hypervascular rim on angiography, and moderately increased signal intensity of the cyst content on T1-weighted MR images, which indicated fluid containing blood and/or necrotic tissue. These findings are helpful in defining the nature of these lesions and strongly suggest that cystic islet cell tumor should be included in the differential diagnosis.

Angiography↗

PubMedDate not supplied

Extended intraarterial cisplatin infusion for treatment of gynecologic cancer after alteration of intrapelvic blood flow and implantation of a vascular access device.

PURPOSE: Twenty-two patients with advanced gynecologic cancer underwent extended intraarterial cisplatin infusion after alteration of the intrapelvic blood flow and implantation of a vascular access device (VAD). METHODS: To maximize concentrations of cisplatin at the target lesion, the superior and inferior gluteal arteries were embolized with steel coils. The tip of the catheter was inserted into the internal iliac artery; the opposite end of the catheter was connected to the VAD. RESULTS: Intensive radioisotope accumulation was demonstrated in the anterior division of the pelvis, seen by scintigraphy performed with technetium 99m macroaggregated albumin via the VAD. Local perfusion in the tumor was well seen by ultrasonographic angiography with CO2 microbubbles via the VAD. Continuous consecutive infusion of cisplatin at a rate of 12.5 mg/day via the VAD minimized the toxicity. The overall response rate was 73%. Radical surgery was possible in 16 of the 22 patients after this intraarterial infusion. CONCLUSION: This method was useful for treating advanced gynecologic cancer without significant toxicity.

Adenocarcinoma↗

PubMedDate not supplied

Subtraction CT with low-flow-rate arterial contrast injection to estimate drug distribution during balloon-occluded arterial chemotherapy infusion for bladder cancer.

PURPOSE: To simulate drug distribution during balloon-occluded arterial chemotherapy infusion (BOAI) for urinary bladder cancer using subtraction computed tomography (CT) with low-flow-rate arterial contrast injection (S-CTLA). METHODS: Ten patients with bladder cancer underwent S-CTLA, and the distribution of contrast agent during BOAI into both internal iliac arteries simultaneously was evaluated in nine pairs of internal iliac arteries and one single artery. For S-CTLA, spiral CT data were acquired before and after 0.2 ml/sec intraarterial injection of contrast material. The enhancement of the urinary bladder wall, the gluteal muscles, and the pelvic bones was categorized using a 4-grade scale. The grades were compared in each of the three pelvic components and differences were tested for significance using the Wilcoxon test for paired groups. RESULTS: S-CTLA revealed the distribution of the contrast agent clearly. Gluteal muscles grades were significantly higher than those of the other two assessed components. CONCLUSION: BOAI does not improve the concentration of contrast agent to the bladder wall over neighboring structures, suggesting that the balloon occlusion technique does not achieve its desired goal for chemotherapy targeting.

Aged↗

PubMedDate not supplied

Vascular access system for continuous arterial infusion of a protease inhibitor in acute necrotizing pancreatitis.

We used a vascular access system (VAS) for continuous arterial infusion (CAI) of a protease inhibitor in two patients with acute necrotizing pancreatitis. The infusion catheter was placed into the dorsal pancreatic artery in the first patient and into the gastroduodenal artery in the second, via a femoral artery approach. An implantable port was then connected to the catheter and was secured in a subcutaneous pocket prepared in the right lower abdomen. No complications related to the VAS were encountered. This system provided safe and uncontaminated vascular access for successful CAI for acute pancreatitis.

Adult↗

PubMedDate not supplied

Retrievable IVC filter: preliminary in vitro and in vivo evaluation.

PURPOSE: To develop an inferior vena cava (IVC) filter that is retrievable even after neointimal formation and incorporation into the caval wall. MATERIALS AND METHODS: Eight filters were placed percutaneously in the infrarenal IVC of eight dogs. Four weeks after placement, percutaneous retrieval of the filters was attempted. Vena cavograms were obtained before and immediately after retrieval. Three dogs were killed immediately after the retrieval procedure was completed. In the other five dogs, follow-up vena cavography was performed 4-14 weeks after retrieval, and autopsy was performed. RESULTS: The filters were placed and retrieved successfully in all eight dogs. No migration, caval penetration, or tilting occurred. The IVCs were completely patent both before and immediately after retrieval in all eight dogs. In the three dogs killed immediately after retrieval, neointimal hyperplasia was seen around the struts, but there was no detachment. Delayed stenosis was not seen in any of the five dogs that were followed up, and the inner surface of the caval wall was smooth. CONCLUSION: This IVC filter can be easily placed and safely retrieved percutaneously, even after neointimal formation.

Animals↗

PubMedDate not supplied

Contrast-enhanced spiral CT of the liver: effect of injection time on time to peak hepatic enhancement.

PURPOSE: On contrast-enhanced hepatic CT, maximum tumor detection of liver metastases from colorectal cancer is achieved at peak hepatic enhancement. We investigated the relationship between injection time of contrast medium and time to peak hepatic enhancement (TPHE) after the end of injection. METHOD: One hundred nineteen patients without a cardiovascular disorder were enrolled in this study. Before the spiral CT was performed, a small amount of contrast medium was injected and a single level dynamic CT was performed to evaluate aortic enhancement and to determine the scan start time of the spiral examination. Patients were divided into three groups; contrast medium was injected over 30 s in 40 patients (Group A), 45 s in 39 patients (Group B), and 60 s in 40 patients (Group C). The TPHE after the end of injection was measured, and the difference among the groups was compared using one-way analysis of variance. A p value of <0.05 was considered a statistically significant difference. RESULTS: The TPHEs of the groups were 25.3 +/- 4.6 s (Group A), 27.0 +/- 5.8 s (Group B), and 24.4 +/- 4.6 s (Group C) and were similar in value. No statistically significant difference was observed (p = 0.067). CONCLUSION: Hepatic enhancement reaches its peak at approximately 25 s after the end of contrast medium injection irrespective of injection time.

Adult↗

PubMedDate not supplied

Influence of liver cirrhosis on pseudolesions in liver at CT during arterial portography.

PURPOSE: Pseudolesions are sometimes seen around the falciform ligament, around the gallbladder, or at the posterior edge of the medical segment on CT during arterial portography. The purpose of this study was to investigate the influence of liver cirrhosis on these pseudolesions. METHOD: The basis of this study was 33 patients with liver cirrhosis or hepatitis (group A) and 43 with neither (group B). The standard for diagnosis was surgical findings. We investigated whether there was a difference in the frequency of each pseudolesion between groups A and B. When tumors were seen in each location, they were excluded from statistical analysis. RESULTS: Pseudolesion around the falciform ligament was seen in none of 32 patients in group A and in 18 of 40 in group B (4 cases were excluded), around the gallbladder in 14 of 30 in group A and 16 of 42 in group B (4 cases were excluded), and at the posterior edge of the medial segment in 13 of 33 in group A and 16 of 42 in group B (1 case was excluded). There was a statistically significant difference in the frequency of pseudolesion around the falciform ligament (p < 0.001, Fisher test), but not around the gallbladder or posterior edge of the medial segment. CONCLUSION: Liver cirrhosis decreases the frequency of pseudolesions around the falciform ligament, but not around the gallbladder or posterior edge of the medial segment.

Adult↗

PubMedDate not supplied

Intrahepatic portosystemic venous shunts: spectrum of CT findings in external and internal subtypes.

PURPOSE: The purpose of this work was to survey the spectrum of CT findings in intrahepatic portosystemic venous shunts (IPSVSs). METHOD: One thousand consecutive liver CT scans examined with an enhanced helical technique were retrospectively reviewed on workstation to find IPSVSs. RESULTS: IPSVSs were noted in 37 patients and divided into two subtypes according to the location of the communicating systemic vein, either outside (external type, n = 34) or within (n = 4) the liver (one patient had both internal and external types). All the external-type shunts were noted in cases with portal hypertension (n = 34). Most shunts (n = 30) ran through segment 4 and/or 3 and came out near the falciform ligament, but five shunts were noted in segment 2 communicating either with the systemic vein (n = 3) or probably with an enlarged left gastric vein (n = 2). Solitary portohepatic venous shunts (internal type) were noted in three cases with (n = 2) or without (n = 1) aneurysmal dilatation and many portohepatic venous shunts in another patient. CONCLUSION: IPSVSs of the external type were far common than those of the internal type, always associated with increased pressure of the portal system and in specific sites probably lacking the hepatic capsule.

Adult↗

PubMedDate not supplied

Residual disease and presence of human papillomavirus after conization.

The objective of this study was to evaluate the incidence of residual disease and the presence of human papillomavirus (HPV) after conization. Data on 53 patients with carcinoma in situ or microinvasive carcinoma who underwent hysterectomy less than 2 months after conization were examined. Seven of 53 patients (13%) had positive margins. In 4 of these 7 patients (57%), residual disease was found in the postconization hysterectomy specimen. Two of 46 patients (4%) with negative margins also had residual disease. HPV DNA was detected by PCR in 27 of 53 conization specimens and in 2 postconization hysterectomy specimens. Of 2 patients, 1 did not have residual disease. Residual disease could be present even with a negative conization margin, and HPV DNA may be found in a histologically normal cervix after conization.

Adult↗

PubMedDate not supplied

Pineal effects on adrenal medulla, area postrema and brain water content in relation to intracranial surgery.

We aimed to explore whether and how the pineal influences the adrenal medulla, the area postrema and the brain water content; and is influenced by sham pinealectomy (SPX) in its structures and melatonin secretion. Quantitative morphological methods were mainly used in rats and golden hamsters. Experimental results showed: (1) Pineal effects on the A cell system of the adrenal medulla were inhibitory to the synthesis and secretion of epinephrine into the perivascular space and stimulatory to the opioid synthesis, and augmented by SPX. Time-of-day changes were also influenced by SPX and PX. (2) The sizes of a part of the nuclei of nerve and glia cells in the area postrema and the brain water content increased by SPX depending on the presence of the pineal, suggesting the pineal's stimulatory effects on these following SPX. (3) SPX caused morphological changes suggesting an increased activity of pinealocytes. However, corresponding consistent increases in plasma melatonin levels were not seen following SPX. Possible interpretations of these observations were discussed.

Adrenal Medulla↗

PubMedDate not supplied

Ultrasonography and computed tomography in adenomyomatosis of the gallbladder.

Ultrasonography and computed tomography were performed in 4 patients with adenomyomatosis of the gallbladder of segmental or diffuse type. Cholecystectomy was performed in all cases, and the diagnosis of adenomyomatosis was confirmed histopathologically. Ultrasonography revealed diffuse or segmental thickening of the gallbladder wall with small intramural diverticula. Small stones were also found. The characteristic findings of adenomyomatosis at computed tomography were soft tissue density masses in the gallbladder fossa, associated with a well-delineated, distinct tumor-free space between the mass and the liver, and with small intramural diverticula and calcified stones within the mass. Ultrasonography and computed tomography demonstrate a characteristic appearance of adenomyomatosis.

Adolescent↗

PubMedDate not supplied

Inhibition of attachment and chemotactic invasion of uterine endometrial cancer cells by a new vinca alkaloid, conophylline.

The effect of conophylline, a new vinca alkaloid that inhibits ras expression, on tumour cell adhesion and infiltration was evaluated using a human endometrial cancer cell line. When SNG-II, a highly differentiated human endometrial cancer cell line, was exposed to conophylline, the cells developed filamentous processes at concentrations which did not affect cell proliferation (0.03-0.3 microgram/ml). After exposure to conophylline (0.3 microgram/ml), cells adherent to matrigel- and type IV collagen-coated wells respectively decreased to 26.9% and 33.3% of the number in the untreated control culture (p < 0.01). In an in vitro invasion assay using a Boyden chamber, infiltration of cells exposed to conophylline decreased to 19.4% (0.3 microgram/ml) (p < 0.01) of the control. In a wound assay, conophylline inhibited the movement of cells at 24 hr after wounding. Flow cytometric analysis revealed that expression of integrin beta 1 was not altered by conophylline, but E-cadherin and CD44 were decreased. The expression of E-cadherin and CD44 could be changed by conophlline.

Antineoplastic Agents, Phytogenic↗

PubMedDate not supplied

A case of deep soft tissue leiomyoma: CT and MRI findings.

A 25-year-old man presented with a firm tissue mass of the right elbow and intermittent pain. CT showed a dumbbell-shaped soft tissue mass with foci of dense calcification in the muscular layer of the triceps brachii muscle and subcutaneous tissue. The tumor showed slightly higher signal intensity on T1-weighted images and markedly higher intensity on T2-weighted images compared with the surrounding muscle. Prominent enhancement was present after the intravenous injection of Gd-DTPA. Histopathological examination of the resected specimen revealed a deep soft tissue leiomyoma.

Adult↗

PubMedDate not supplied

Postsurgical intrahepatic portal thromboembolism: a possible cause of perfusion defects on CT during arterial portography.

OBJECTIVE: Our goal was to investigate unexplained nontumorous perfusion defects on CT arterial portography (CTAP). MATERIALS AND METHODS: The CTAP images of 35 patients who underwent partial hepatectomy or open biopsy were analyzed. Hepatic tumors consisted of hepatocellular carcinoma (n = 18) and colorectal carcinoma metastases (n = 17). Nontumorous perfusion defects were categorized into those previously explained and those unexplained. We investigated unexplained ones and their relationship with the underlying conditions. RESULTS: Eight unexplained nontumorous perfusion defects were found in four patients with colorectal metastases. Statistical analysis showed that the defects occurred with significantly higher incidence in patients with colorectal metastases than in those with hepatocellular carcinoma (p = 0.046, Fisher test). All four patients with defects underwent CTAP within 1 month after colorectal surgery. A significant difference was seen in the distribution of surgery-CTAP time intervals between those patients with and those without defects (p < 0.05, Wilcoxon-Mann-Whitney test). Intrahepatic portal thrombi were pathologically proven in one of the four patients. CONCLUSION: Unexplained nontumorous hepatic perfusion defects may represent postsurgical portal thromboemboli.

Adult↗