Biomedical subjects

Y Takase

Publications and source records attributed to Y Takase.

At least 37 records · Page 2Linked to original sources

PubMed2000

Persistent trigeminal artery variants detected by MR angiography.

Persistent trigeminal artery (PTA) variants are cerebellar arteries that originate directly from the precavernous portion of the internal carotid artery (ICA). The goal of our study was to determine the incidence and MR angiographic features of PTA variants. Between April 1996 and September 1999, 523 cranial MR angiographies were performed at our institution. Most of the patients examined had or were suspected of having cerebrovascular disease. We retrospectively reviewed these 523 MR angiograms. A 1.5-T scanner was used in all studies, and maximum intensity projection (MIP) images obtained using the three-dimensional time-of-flight (3D TOF) technique were displayed stereoscopically. Four PTA variants were detected on MR angiograms, at a rate of 0.76%. At least three of the four PTA variants were anterior inferior cerebellar arteries (AICAs), small tortuous arteries arising from the precavernous portions of the ICAs and taking a posterior course. Although the clinical significance is not great, we found a relatively high incidence of PTA variants on MR angiograms. We stress that knowledge and recognition of these anomalous cerebellar arteries are useful and important in the interpretation of cranial MR angiograms.

Arteries↗

PubMed2000

Middle cerebral artery variations detected by magnetic resonance angiography.

Middle cerebral artery (MCA) variations are found incidentally on cranial magnetic resonance angiography (MRA). Our goal was to examine the incidence and types of MCA variations detected by MRA. Between April 1996 and March 1999, cranial MRA was performed in 432 cases at our institution. Most of the patients examined had or were suspected to have cerebrovascular disease. After excluding 7 patients with moyamoya disease, we retrospectively reviewed 425 MRA results. A 1.5-T scanner was used in all studies, and maximum-intensity projection images obtained using the three-dimensional time-of-flight technique were displayed stereoscopically. In the 425 patients MRA revealed 16 anomalous MCAs, including 9 duplicated MCAs, 5 accessory MCAs, and 2 fenestrated MCAs, which is a rate of 3.8%. Thus, although the clinical significance is not great, we found a relatively high incidence of anomalous MCAs on MRA. We stress that knowledge and recognition of these variations are useful and important during the interpretation of cranial MRA.

Adolescent↗

PubMed2000

The essential interaction between yeast mRNA capping enzyme subunits is not required for triphosphatase function in vivo.

The Saccharomyces cerevisiae mRNA capping enzyme consists of two subunits: an RNA 5'-triphosphatase (Cet1) and an mRNA guanylyltransferase (Ceg1). In yeast, the capping enzyme is recruited to the RNA polymerase II (Pol II) transcription complex via an interaction between Ceg1 and the phosphorylated carboxy-terminal domain of the Pol II largest subunit. Previous in vitro experiments showed that the Cet1 carboxy-terminal region (amino acids 265 to 549) carries RNA triphosphatase activity, while the region containing amino acids 205 to 265 of Cet1 has two functions: it mediates dimerization with Ceg1, but it also allosterically activates Ceg1 guanylyltransferase activity in the context of Pol II binding. Here we characterize several Cet1 mutants in vivo. Mutations or deletions of Cet1 that disrupt interaction with Ceg1 are lethal, showing that this interaction is essential for proper capping enzyme function in vivo. Remarkably, the interaction region of Ceg1 becomes completely dispensable when Ceg1 is substituted by the mouse guanylyltransferase, which does not require allosteric activation by Cet1. Although no interaction between Cet1 and mouse guanylyltransferase is detectable, both proteins are present at yeast promoters in vivo. These results strongly suggest that the primary physiological role of the Ceg1-Cet1 interaction is to allosterically activate Ceg1, rather than to recruit Cet1 to the Pol II complex.

Acid Anhydride Hydrolases↗

PubMed2000

Blood supply routes of recurrent esophageal varices following endoscopic embolization.

BACKGROUND/AIM: The blood supply routes of recurrent esophageal varices following complete endoscopic embolization (EE) are not yet known. The purpose of this study is to identify these blood supply routes by comparing endoscopic varicography and percutaneous transhepatic portography (PTP). METHODS: Eleven cases of recurrent esophageal varices following EE are included in this study. The blood supply routes of primary and recurrent varices were analyzed by comparing the varicography obtained at the initial and repeat EE with PTPs before and after the initial EE. RESULTS: Endoscopic varicography at the time of initial EE could show the vessels of the left gastric vein (LGV) system, such as the cardiac branch of the LGV, and the cardiac venous plexus (CP) in 100% of cases, and the trunk of the LGV in 73% (8/11) of cases, whereas the posterior gastric vein was seen in only 18% (2/11) of cases. PTP performed 2 weeks after the initial EE confirmed that the routes visualized by endoscopic varicography could be obliterated in 10 of 11 cases. The blood supply routes of recurrent varices, demonstrated by varicography, were the vessels of the short gastric vein (SGV) system, such as the fundic branch of the SGV or the posterior gastric vein in 82% (9/11) of cases, and the partially reformed fine CP in 27% (3/11) of cases. Varicography revealed the remnant vessels of the LGV in only 1 case. CONCLUSIONS: The primary esophageal varices are supplied with blood mainly from the cardiac branch of the LGV through the CP. However, the blood supplies of recurrent varices following EE come from the fundic branch of the SGV or the posterior gastric vein. We conclude that three-dimensional obliteration of esophageal varices and their feeders, the LGV and SGV systems, is completed by initial and repeat EEs.

Adult↗

PubMed2000

Urgent transjugular retrograde obliteration for prophylaxis of rebleeding from gastric varices in patients with a spontaneous portosplenorenal shunt.

BACKGROUND: Bleeding isolated gastric varices with a spontaneous portosplenorenal shunt are difficult to control. The urgent use of transjugular retrograde obliteration (TJO) to prevent early rebleeding and to improve early mortality has not yet been demonstrated. We report our experience with this technique in patients with isolated gastric varices after treatment of acute bleeding. METHODS: We reviewed our experience of 6 patients with isolated gastric varices with a spontaneous portosplenoral shunt treated with TJO after treatment of acute bleeding. We basically applied endoscopic glue embolization using cyanoacrylate monomer for treatment of acute bleeding. TJO was a method using an occlusive balloon catheter to control a spontaneous portosplenorenal shunt flow while injecting sclerosant retrograde into the gastric varices. RESULTS: Treatment of acute bleeding was achieved immediately by endoscopic glue embolization, endoscopic variceal ligation, and ligating the varices with sutures following anterior gastrotomy in 4, 1 and 1 patients, respectively, and then TJO was performed. Permanent hemostasis and variceal eradication was achieved in these 6, and they all survived. They were alive for 6-66 months without gastric variceal recurrence. CONCLUSIONS: We conclude that urgent TJO is effective in the prophylaxis of early and late rebleeding from isolated gastric varices in patients with a spontaneous portosplenorenal shunt.

Adult↗

PubMed2000

Short-term hemodynamic effects of transjugular retrograde obliteration of gastric varices with gastrorenal shunt.

OBJECTIVES: The purpose of this study was to investigate the short-term effects on portal hemodynamics of transjugular retrograde obliteration (TJO) of gastric varices with gastrorenal shunt. METHODS: Thirty patients with gastric varices and a gastrorenal shunt were included in this study. The patients ranged in age from 42 to 75 years (16 men and 14 women), and according to Child's classification, class A, B and C cirrhosis was seen in 1, 13 and 16 patients, respectively. The portal blood flow was measured by an ultrasonic duplex Doppler system, and the wedged hepatic venous pressure was measured by hepatic venous catheterization, before and after TJO. RESULTS: Complete obliteration of the gastrorenal shunt and gastric varices was revealed by retrograde inferior phrenic venography and computed tomography after TJO in all cases. The wedged hepatic venous pressure was significantly increased the day after TJO compared with that before therapy (257 +/- 71 vs. 307 +/- 73 mm H(2)O, p < 0.01). The portal venous flow was significantly increased 1 week after TJO compared with that before therapy (744 +/- 190 vs. 946 +/- 166 ml/min, p < 0.01). The serum albumin levels before and after TJO were 3.0 +/- 0.4 and 3.1 +/- 0.5 g/dl, respectively, and the total bilirubin levels were 1.5 +/- 0.7 and 1. 5 +/- 0.8 mg/dl, respectively, neither of these parameters changing significantly. The plasma ammonia levels before and after TJO were 109 +/- 62 and 67 +/- 31 microg/dl, and the indocyanine green retention rates at 15 min were 31 +/- 13 and 24 +/- 13%, both showing a significant change (p < 0.01 and p < 0.05, respectively). CONCLUSIONS: We conclude that TJO increases portal blood flow which contributes to the decrease in plasma ammonia levels and the indocyanine green retention rate, although increasing the wedged hepatic venous pressure.

Adult↗

PubMed2000

Short-term portal hemodynamic effects of endoscopic embolization for esophageal varices.

BACKGROUND/AIM: Endoscopic embolization (EE) is a specialized treatment that obliterates esophageal varices along with their associated blood supply. The purpose of this study was to investigate the short-term effects of EE for esophageal varices on portal hemodynamics and liver function. METHODS: Thirty patients with esophageal varices were included in this study. The portal blood flow was measured by an ultrasonic duplex Doppler system before and after EE. EE was performed by freehand intravariceal injection of 5% ethanolamine oleate with iopamidol with the aid of a balloon attached to the tip of an endoscope under fluoroscopy. RESULTS: For the blood supply system, endoscopic varicography at the time of EE was able to show the vessels of the cardiac branch of the left gastric vein in 93% of the cases, the cardiac venous plexus in 90%, the trunk of the left gastric vein in 27%, the lesser curvature branch of the left gastric vein in 10%, the fundic branch of the short gastric vein in 13%, and the posterior gastric vein in 13%. For the blood drainage system, endoscopic varicography was able to show the paraesophageal vein in 39% of the cases, the inferior phrenic vein in 17%, and the mediastinal vein in 13%. No clotting was detected after EE in the intra- and extraportal veins in any of the cases. The flow velocities in the main portal vein before and after EE were 14.2+/-3.2 and 15.5+/-3.5 cm/s, respectively, showing no significant change. The cross-sectional area of the portal vein before and after EE was 0.96+/-0.21 and 1.04+/-0.23 cm(2), and the flow volume of the portal vein was 817+/-288 and 930+/-189 ml/min, both also showing no significant change. The blood laboratory parameters showed no significant change after EE. CONCLUSIONS: We conclude that neither portal blood flow nor liver function were damaged by EE, although both the varices and their associated blood supply were obliterated.

Aged↗

PubMed2000

[An autopsy case of malignant lymphoma who showed hearing loss and cavernous sinus syndrome in the first stage and hemophagocytic syndrome].

A 48-year-old man was admitted to our hospital due to multiple cranial neuropathy such as vertigo, hearing loss of the left ear, visual loss of the left eye, left ptosis and total ophthalmoplegia of the left eye. Brain MRI revealed no abnormalities. After 10 days, he suddenly showed hemophagocytic syndrome with high fever, liver dysfunction, jaundice and pancytopenia. In spite of the treatment, he died of multiple organ failure after 26 days. At autopsy, malignant lymphoma cells of T cell origin directly invaded into the liver, spleen, intraperitoneal lymph nodes and other organs. Reports that direct invasion of lymphoma cells could be detected at the cranial nerves in the cavernous sinus are very rare.

Cavernous Sinus↗

PubMed1999

Preoperative anal sphincter high pressure zone, maximum tolerable volume, and anal mucosal electrosensitivity predict early postoperative defecatory function after low anterior resection for rectal cancer.

PURPOSE: The aims of this study were to correlate postoperative defecatory function after low anterior resection with clinical factors and physiologic parameters and to explore the possibility of predicting early postoperative defecatory function after low anterior resection. METHODS: Thirty-two patients who underwent low anterior resection for rectal cancer were studied. Anorectal physiologic studies were performed preoperatively and six months postoperatively; maximum resting pressure, maximum squeeze pressure, length of the high pressure zone, neorectal sensory threshold, neorectal maximum tolerable volume, and anal mucosal electrosensitivity were recorded. Preoperative and postoperative defecatory function was scored between 0 (worst) and 6 (best) on the basis of bowel frequency, fecal incontinence, and urgency. RESULTS: In univariate regression analyses, a longer preoperative high pressure zone and a more sensitive anal mucosa were associated with better postoperative defecatory function. Using multiple regression analysis, in which age, gender, the level of anastomosis, and preoperative physiologic parameters were examined as independent variables, a longer preoperative high pressure zone, a larger preoperative maximum tolerable volume, and lower sensory threshold of the anal canal were associated with better postoperative defecatory function. Postoperative function score was found to be predictable using the following formula: 1.47 + 0.496 x high pressure zone (cm) + 0.007 x maximum tolerable volume (ml) - 0.247 x sensory threshold (mA) of the anal canal. CONCLUSION: Early postoperative defecatory function after low anterior resection is predictable from preoperative high pressure zone, maximum tolerable volume, and anal mucosal electrosensitivity.

Aged↗

PubMed1999

Thallium-201 SPECT of adjacent intracranial tumours: a contrast in thallium kinetics.

We report a case of adjacent intracranial tumours: malignant fibrous histiocytoma (MFH) and meningioma. Thallium-201 single-photon emission computed tomography demonstrated different thallium kinetics between the tumours (slow washout from the MFH and rapid clearance in the meningioma) and could be said to have been useful for preoperative histological estimation.

Aged↗

PubMed1999

Carrier-mediated absorption of salicylic acid from hamster cheek pouch mucosa.

Previously, we found that monocarboxylic acids undergo carrier-mediated transport in primary cultures of oral mucosal epithelial cells.1 In this study, we investigated whether carrier-mediated absorption of a monocarboxylic acid from the oral mucosa occurs in vivo. Salicylic acid was administered to hamster cheek pouch. At predetermined intervals, the concentration of salicylic acid in the fluid remaining in the cheek pouch lumen and the blood salicylic acid concentration were determined. The absorption of salicylic acid was saturable at high salicylic acid concentrations. Sodium azide, a metabolic inhibitor, and carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP), a protonophore, significantly inhibited the absorption of salicylic acid but not the absorption of salicylamide from the oral mucosa. Various monocarboxylic acids inhibited the absorption of salicylic acid, whereas dicarboxylic acids had no such effect. Transfer of [14C]salicylic acid from the cheek pouch mucosa to the systemic circulation was observed, and the blood [14C]salicylic acid concentration in the case of coadministration with propionic acid was significantly lower than that in the case of no propionic acid coadministration. These results show that monocarboxylic acids undergo carrier-mediated absorption from the hamster cheek pouch mucosa.

Absorption↗

PubMed1999

[Infectious complications in patients with ulcerative colitis].

Several infectious disease play a role in altering the clinical course of ulcerative colitis(UC). Such infections are considered to be opportunistic infections. Especially cytomegalovirus(CMV) infection is a famous exacerbating factor. We describe a case of fulminant ulcerative colitis with methicillin-resistant staphylococcus aureus (MRSA) infection. A 55-year-old man was admitted to the hospital because of yellowish watery diarrhea. Antibiotics were administered, but the patient's condition was not improved. On the 9th hospital day, a stool culture yielded MRSA. On the 12th hospital day the patient developed toxic megacolon. Colonoscopic examination revealed the characteristic signs of UC. He underwent the emergency total colectomy and ileostomy. We emphasize in this article that MRSA infections should be recognized as an exacerbating factor of UC.

Colitis↗

PubMed1998

4-Benzylamino-1-chloro-6-substituted phthalazines: synthesis and inhibitory activity toward phosphodiesterase 5.

We synthesized various 4-benzylamino-1-chloro-6-substituted phthalazines (15) and 4-benzylamino-1-chloro-7-substituted phthalazines (16) and evaluated their inhibitory activity toward phosphodiesterase 5 (PDE5) purified from porcine platelets. The PDE5-inhibitory activities of 15 were greater than those of the isomers (16). The preferred substituent at the 4-position of phthalazine was a (3-chloro-4-methoxybenzyl)amino group, and those at the 6-position were cyano, nitro, and trifluoromethyl groups. Compounds 15a (IC50 = 4.8 nM), 15f (3.5 nM), and 15i (5.3 nM) were more potent inhibitors than E4021 (8.6 nM). Compounds 15a and 15f also showed vasorelaxant activity in isolated porcine coronary arteries precontracted with prostaglandin F2alpha (10(-5) M). The EC50 values for vasorelaxant action of 15a, 15f, and E4021 were 150, 160, and 980 nM, respectively. These results show that novel PDE5 inhibitors possessing a potent vasorelaxant effect may exist among phthalazine derivatives.

3',5'-Cyclic-GMP Phosphodiesterases↗

PubMed1998

Primary Sjögren's syndrome complicated by sarcoidosis.

Sjögren's syndrome and sarcoidosis share several common features, such as keratoconjunctivitis sicca, swelling of parotid glands, lung involvement, cutaneous anergy, T cell-mediated immunodeficiency, an increased CD4+/CD8+ lymphocyte ratio, and association with the human leucocyte antigen (HLA)-B 8 and DR 3 haplotypes. However, only five patients with primary Sjögren's syndrome and sarcoidosis have been previously reported in the English language literature. The rare case of a 49-year-old Japanese woman with primary Sjögren's syndrome complicated by sarcoidosis is described. The serum angiotensin-converting enzyme level was increased, and histological examination of lung and skin biopsies revealed noncaseating granulomas, indicating that her primary Sjögren's syndrome was complicated by sarcoidosis.

Female↗

PubMed1998

[A case of musicogenic epilepsy induced by listening to an American pop music].

This is the second report of musicogenic epilepsy in Japan. A 23-year-old woman was admitted to our hospital due to the musicogenic epilepsy. She had four generalized tonic clonic seizures at 18 and 19 years old. Since 19, she had had complex partial seizures lasting for about 20 seconds which was easily evoked by listening to an American pops particularly "Dreamlover" song by Mariah Carey. Brian MRI and interictal 99mTc HMPAO-SPECT showed no abnormalities. In the ictal EEG recording, three minutes after listening to the song, seizure activities were recorded from the right temporal region with 11Hz rhythmic epileptiform activities over the right temporal region and subsequent delta activities over the right hemisphere. The song that induced the seizure had a specific meaning that might evoke her emotion as had been pointed out in the previous reports.

Adult↗

PubMed1997

Intraorbital wooden and bamboo foreign bodies: CT.

We describe the CT findings of intraorbital wooden and bamboo foreign bodies in the acute, subacute, and chronic stages. We examined four patients using CT a total of seven times. The CT findings were reviewed. There were three dry wooden foreign bodies. CT within a day of the accident demonstrated wooden foreign bodies as low density relative to surrounding orbital fat, while CT 8-29 days after the accident showed them as denser than the extraocular muscles. In the acute stage, dry wooden foreign bodies mimic air bubbles. Wooden foreign bodies in the subacute and chronic stages should be included in the differential diagnosis of intraorbital lesions of soft tissue density or above on CT of traumatised orbits. There was one dry bamboo foreign body. Within a day of the accident it was recognised as linear lesion isodense with fat. Therefore, such foreign bodies may be missed on CT when located in the orbital fat.

Adipose Tissue↗

PubMed1997

Childhood bronchial mucoepidermoid tumors.

A very rare case of a childhood bronchial mucoepidermoid tumor is presented. A 4-year-old girl was hospitalized with prolonged pneumonia. Computed tomography of the chest showed a tumor with calcifications in the right upper lobe. Subsequently, the patient underwent right upper lobectomy. Histologically, the tumor was a low-grade mucoepidermoid tumor originating from the bronchus. Three years postoperatively there has been no evidence of disease. A review of the literature indicates that 30 cases of bronchial mucoepidermoid tumors in children have been reported. Symptoms result from associated bronchial obstruction. Children with recurrent or prolonged pneumonia should undergo aggressive diagnostic investigation by chest tomography or bronchoscopy. Appropriate therapy for childhood bronchial mucoepidermoid tumor is total resection of the lesion while sacrificing as little of the normal lung tissue as possible.

Airway Obstruction↗

PubMed1997

An improved endoscopic variceal ligation for esophageal and solitary gastric varices--three-O-band-shooter.

We have reported a 16.0 mm long new type of instrument with the inner diameter of inner cylinder of 10.3 mm for endoscopic variceal ligation which could shoot 3 elastic O bands continuously in short period of time without removing the endoscope. The suction volume of new instrument is larger than that of the Stiegmann's ligator. We performed endoscopic variceal ligation (EVL) in 17 cases of the esophageal varix and 8 cases of the solitary gastric varix. EVL was performed as prophylaxis as all the cases. The esophageal varices were eliminated in all the cases after ulcer formation. The procedure was performed one time in 15 cases and two times in the remaining 2 cases. Three patients died one to hepatic failure during the follow-up period between 4 and 16 months. Six and twelve months cumulative recurrence rates were 30% and 48% respectively. On the other hand all the gastric varices disappeared after one sitting of the treatment. There was one variceal recurrence during the follow-up period. Computed tomography and/or arterioportography performed before had showed patent gastro-renal shunt in five cases. No change in the shunt was observed after the treatment. No serious complications due to EVL was encountered in all the cases. Therefore, it is thought that this method can be used for the treatment of not only esophageal varices but also gastric varices.

Endoscopes↗