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Biomedical subjects

Y Okuda

Publications and source records attributed to Y Okuda.

At least 469 records · Page 26Linked to original sources
PubMedDate not supplied

In vitro transmission of duck hepatitis B virus to primary duck hepatocyte cultures.

An attempt was made to infect primary duck hepatocyte cultures with duck hepatitis B virus in vitro in order to clarify the biology of hepatitis B virus. Livers of ducklings, 0 to 17 days posthatch, without viremia were digested ex situ by perfusion of collagenase solution through the portal or hepatic vein. Homogeneous hepatocyte suspensions were seeded into plastic dishes in L-15 medium containing 10(-8) M insulin, 2 X 10(-8) M glucagon and 10(-8) M dexamethasone and were subsequently inoculated with sufficient numbers of duck hepatitis B virus. As a result, duck hepatitis B virus multiplication started weakly on Day 2, gradually increased and reached the maximum level approximately on Day 10 postinoculation. Viral replication was revealed by duck hepatitis B virus DNA in the cell pellet and in the culture medium and duck hepatitis B virus DNA-specific transcripts in the cell pellet. Immunostaining demonstrated duck hepatitis B virus core antigen in approximately 10% of cultured hepatocytes, and an increase in numbers of positive cells was not observed with time for up to 18 days of culture. Viral particles were found within the endoplasmic reticulum, and the inoculation of culture medium provoked viremia in the ducklings. The age of ducklings did not influence the numbers of cells infected. The in vitro infection system was similar to the in vivo one; however, the former seemed to be age-independent and to allow replication of duck hepatitis B virus in the limited number of hepatocytes.

Animals↗
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Treatment of Takayasu's aortitis with self-expanding metallic stents (Gianturco stents) in two patients.

Gianturco self-expanding metallic stents were successfully placed to treat incomplete balloon dilatation of the abdominal aorta in 2 patients with Takayasu's aortitis. In 1 case eleven 1-cm long, 1-cm diameter stents were inserted in tandem to bridge a long stenosis. In the other patient, four stents 1.5 cm long, 1.5 cm in diameter were inserted in tandem to bridge what had been a complete occlusion prior to balloon angioplasty. Clinical symptoms, as well as angiographic findings, improved significantly after placement of the stents. The patients underwent repeat aortography at 10 and 8 months, respectively, and were followed clinically for a total of 18 months and 15 months, respectively, without clinical evidence of deterioration. Our results show the usefulness of expandable metallic stents in the treatment of aortic stenosis due to Takayasu's aortitis that remains unresponsive to balloon dilatation.

Adult↗
PubMedDate not supplied

Percutaneous internal fistulization of a lung abscess after incomplete external drainage.

Internal drainage was performed with expandable metallic stents in a 79-year-old male with lung abscess secondary to bronchogenic carcinoma. Initial external drainage was prolonged, and internalization of drainage allowed removal of the external drainage catheter. Connection of abscess cavity to obstructed bronchus was created after passing a steerable guidewire percutaneously through the abscess into the bronchus. This new type of internal drainage technique may be applicable to patients with prolonged standard percutaneous external drainage of lung abscesses.

Aged↗
PubMedDate not supplied

Expandable metallic stent treatment for malignant colorectal strictures.

Four patients were treated by placement of an expandable metallic stent (two Gianturco Z-stents, two Ultraflex stents) for malignant colorectal strictures. All four patients were able to defecate after stent placement. Stent migration was recognized in one patient. Two patients suffered from tenesmus after stent placement.

Aged↗
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Long-term effects of eicosapentaenoic acid on diabetic peripheral neuropathy and serum lipids in patients with type II diabetes mellitus.

The present study was undertaken to investigate the efficacy of a new, highly purified (purity greater than 91%), ethyl esterification product from natural eicosapentaenoic acid (EPA-E, C20:5 omega 3) in patients with type II diabetes mellitus (NIDDM). Hemodynamic changes were assessed at the level of the dorsalis pedis artery using an ultrasonic color Doppler duplex system before and after oral administration of EPA-E at a dose of 1800 mg/day for 48 weeks. The cross-sectional area of the dorsalis pedis artery increased significantly from 2.5 +/- 0.2 to 3.9 +/- 0.4 mm2 (48 weeks, mean +/- SE, p < 0.05). Moreover, EPA-E improved the clinical symptom (coldness, numbness) as well as the vibration perception threshold sense of the lower extremities [from 32.1 +/- 8.5 to 16.1 +/- 4.8 (48 weeks) microns]. A significant decrease of serum triglycerides was also noted by EPA-E administration. Furthermore, significant decrease of the excretion of albumin in urine [from 24.4 +/- 3.3 to 13.9 +/- 1.8 (48 weeks) mg/g.Cr, p < 0.05]. The results of this study suggest that EPA-E has significant beneficial effects on diabetic neuropathy and serum lipids as well as other diabetic complications such as nephropathy and macroangiopathy.

Adult↗
PubMedDate not supplied

Delayed severe airway obstruction due to hematoma following stellate ganglion block.

BACKGROUND AND OBJECTIVES: Delayed onset of airway obstruction following stellate ganglion block (SGB) may be life threatening. We treated a patient who developed a severe airway obstruction caused by a large hematoma several hours after an SGB. METHODS: A 62-year-old woman suffering from sudden deafness developed dyspnea 2 hours after undergoing her fourth SGB, and evidenced swelling and tenderness in her anterior neck and chest. Her pharyngolaryngeal tissues were edematous, and the glottis was markedly narrowed. Computed tomograms and magnetic resonance images revealed a large soft tissue mass extending from the first cervical vertebra to the diaphragm. RESULTS: Surgical tracheotomy was performed to maintain her airway. Swelling of the vocal cord disappeared on the eleventh day after the operation. CONCLUSIONS: We believe that the SGB needle injured the vertebral artery and caused massive hemorrhage anterior to the cervical vertebra, subsequently inducing pharyngolaryngeal edema by obstructing the venous and lymphatic drainage of the cervical region.

Airway Obstruction↗
PubMedDate not supplied

Excision of spinal tumor in a patient with severe pulmonary dysfunction using combined spinal and epidural anesthesia with two epidural catheters.

BACKGROUND AND OBJECTIVES: Combined spinal and epidural anesthesia (CSEA) has become common practice. We performed CSEA using two epidural catheters in a 69-year-old female with severe pulmonary dysfunction caused by a diaphragmatic hernia, who underwent surgical excision of a lumbar spinal tumor. METHODS: Combined spinal and epidural anesthesia was performed using two epidural catheters to minimize postoperative pulmonary complications. One epidural catheter was inserted above the surgical region, at the T11-12 interspace, and another one below the surgical region, via the sacral hiatus. Spinal anesthesia was produced using the L5-S1 interspace and 3 mL 0.5% bupivacaine. Oxygen, 3 L/min, was administered through a face mask during surgery. RESULTS: Fifteen minutes after spinal anesthesia, analgesic level was confirmed below T7 using the pinprick method. The patient complained of pain in the surgical region 10 minutes after the dura mater was opened. We injected 5 mL 2% mepivacaine through the upper epidural catheter to relieve the pain. We also injected 10 mL 2% mepivacaine through the lower catheter when she felt pain in the right leg. The perioperative course was uneventful. Oxygen saturation was maintained above 95%. CONCLUSIONS: Combined spinal and epidural anesthesia using two epidural catheters was used successfully to excise a spinal tumor in a patient with severe pulmonary dysfunction.

Anesthesia, Epidural↗
PubMedDate not supplied

Use of computed tomography for maxillary nerve block in the treatment of trigeminal neuralgia.

BACKGROUND AND OBJECTIVES: Maxillary nerve block has traditionally been performed by using external anatomic landmarks. However, the classic approach to the nerve may be confounded because of anatomic variability. We describe a technique for the block using the suprazygomatic route guided by computed tomography (CT). CASE REPORT: A 90-year-old woman had a 30-year history of episodic pain in her right maxillary region. We attempted to block the maxillary nerve with classic technique, but we could not identify the nerve by eliciting paresthesia. In addition, bleeding was noted after repeated attempts. To minimize complications and confirm the correct position of the needle tip, we planned the block with a suprazygomatic approach using CT guidance. The needle was inserted without paresthesia. The CT scan showed the needle tip was placed at the entrance of the pterygopalatine fossa and the distribution of contrast medium spread appropriately around the pterygopalatine fossa. After confirming the clinical effect and lack of complications of the block using the local anesthetic, 0.5 mL of 7% phenol was injected. This technique resulted in complete sensory loss in the area innervated by the maxillary nerve, and did so without complications. CONCLUSIONS: A maxillary nerve block guided by a CT imaging is an alternative to classic techniques.

Aged↗
PubMedDate not supplied

Acute cigarette smoking reduces vasodilative effect induced by sympathetic block in dogs.

BACKGROUND AND OBJECTIVES: The aim of this study is to clarify the influence of acute cigarette smoking on vasodilation induced by sympathetic block. METHODS: We measured mean arterial pressure, heart rate, left brachial artery blood flow (BABF), right femoral artery blood flow (FABF), and plasma catecholamines in dogs to examine the effect of acute cigarette smoking after stellate ganglion block (SGB). The experimental protocol was: (1) Left SGB using 1.0 mL 0.5% mepivacaine without smoking (sham smoking); and (2) left SGB using 1.0 mL 0.5% mepivacaine followed by a single cigarette smoking (nicotine 1 mg) 15 minutes after the block. RESULTS: SGB induced a significant increase of BABF during the study (baseline, 100%; peak at 10 minutes after SGB, 176% +/- 9%; P <.05) in sham smoking and a significant decrease of FABF from 10 minutes after the block to 20 minutes after sham smoking (baseline, 100%; bottom at 5 minutes after sham smoking, 82% +/- 8%; P <.05). Smoking after SGB induced a significant decrease of BABF 60 minutes after smoking (baseline, 100%; 69% +/- 11%; P <.05) and a significant decrease of FABF during the study (baseline, 100%; bottom at 20 minutes after smoking, 74% +/- 20%; P <.05). Smoking significantly increased plasma norepinephrine and epinephrine through the study. CONCLUSIONS: Sympathetic block induces a significant increase of peripheral blood flow, but smoking produces a significant decrease in the blood flow in the SGB-induced dilated vessels.

Anesthetics, Local↗