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Y Okada

Publications and source records attributed to Y Okada.

At least 325 records · Page 18Linked to original sources

[Evaluation of varicocele by ultrasonography through a water bag in the supine position].

Recently, ultrasonography has been widely used to evaluate varicocele. However, it is difficult to obtain reproducible scrotal images with a hand probe in the standing position. We, therefore, applied the water bag technique during ultrasonographic examination of the scrotal contents in the supine position. The ultrasonographic images thus obtained were compared with physical findings and scrotal scintigraphic findings. Forty-five varicocele patients diagnosed by palpation and ultrasonography were enrolled in this study. An ultrasonographic examination through a water bag in the supine position has the following advantages 1) it is easy to perform and stable images are obtained, 2) varicoceles that are not palpable can be detected and 3) examinations can be repeated both pre- and postoperatively. Of the 45 patients, 39 and 41 had positive findings on the ultrasonographic images and physical examinations, respectively. Four patients had negative findings on physical examination but positive findings on the ultrasonographic images. Thus, ultrasonographic images through a water bag in the supine position proved to be a useful method of confirming the hemodynamics in varicoceles.

Adolescent↗

[Anesthetic management for a patient with autoimmune hemolytic anemia].

A 69-year-old woman with autoimmune hemolytic anemia (AIHA) received gastric resection and splenectomy under general anesthesia combined with epidural anesthesia. Her blood type had been determined as type A, Rh type CCDee, with anti-e-antibody and anti-pdl-antibody positive as autoantibodies. We applied the technique of hemodilutional autologous transfusion to supplement the blood loss during the operation to prevent hemolysis or occurrence of new antibody after homologous transfusion. We should pay much attention to a patient with AIHA to find signs of peri-operative hemolysis and to give the treatment for hemolysis in early stage. We consider that the hemodilutional autologous transfusion is a useful technique for the anesthetic management of the patient having a rare blood type.

Aged↗

Identification of multiple cis-acting elements mediating the induction of prostaglandin G/H synthase-2 by phorbol ester in murine osteoblastic cells.

The tumor promoter phorbol 13-myristate 12-acetate (PMA), the best characterized protein kinase C agonist, frequently regulates gene expression via activation of Fos/Jun (AP-1) complexes. PMA rapidly and transiently induces prostaglandin G/H synthase-2 (PGHS-2) expression in murine osteoblastic MC3T3-E1 cells, but no functional AP-1 binding motifs in the 5'-flanking region have been identified. In MC3T3-E1 cells transfected with -371/+70 bp of the PGHS-2 gene fused to a luciferase reporter gene (Pluc), PMA stimulates luciferase activity up to eightfold. Computer analysis of the sequence of the PGHS-2 promoter region identified three potential AP-1 elements in the -371/+70 bp region, and deletion analysis suggested that the sequence 5'-aGAGTCA-3' at -69/-63 bp was most likely to mediate stimulation by PMA. Mutation of the putative AP-1 sequence reduces the ability of PMA to stimulate Pluc activity by 65%. On electrophoretic mobility shift analysis (EMSA), PMA induces binding to a PGHS-2 probe spanning this sequence, binding is blocked by an unlabeled AP-1 canonical sequence, and antibodies specific for c-Jun and c-Fos inhibit binding. Mutation of this AP-1 site also causes a small (22%) but significant reduction in the serum stimulation of Pluc activity in transiently transfected MC3T3-E1 cells. On EMSA, serum induces binding to a PGHS-2 probe spanning the AP-1 site, binding is blocked by an unlabeled AP-1 canonical sequence, and antibodies specific for c-Jun and c-Fos inhibit binding. Joint mutation of this AP-1 site and the nearby CRE site at -56/-52 bp, previously shown to mediate serum, v-src and PDGF induction of PGHS-2 in NIH-3T3 cells, blocks both PMA and serum induction of Pluc activity in MC3T3-E1 cells. Hence, the AP-1 and CRE binding sites are jointly but differentially involved in both the PMA and serum stimulation of PGHS-2 promoter activity.

3T3 Cells↗

Coexpression of VEGF receptors VEGF-R2 and neuropilin-1 in proliferative diabetic retinopathy.

PURPOSE: To elucidate vascular endothelial growth factor (VEGF)-mediated pathogenesis of fibrovascular proliferation in diabetic retinopathy. METHODS: Fibrovascular tissues were obtained at vitrectomy from 22 cases with proliferative diabetic retinopathy. The half-divided tissues were processed for reverse transcription-polymerase chain reaction (RT-PCR) analysis to examine the expression of VEGF isoforms and their receptors. Paraffin sections of the other half were used for immunohistochemistry for CD34, glial fibrillary acidic protein and VEGF, and in situ hybridization for VEGF. RESULTS: RT-PCR analysis demonstrated the expression of VEGF receptors VEGF-R1, VEGF-R2, and neuropilin-1 in 12, 14, and 14 of 22 cases, respectively. Notably, VEGF-R2 and neuropilin-1 were simultaneously expressed in the identical 14 tissues. The isoform VEGF121 was constitutively expressed in all the tissues examined, whereas the expression of VEGF165 was confined to the 7 tissues that also expressed VEGF-R2 and neuropilin-1. The vascular density of fibrovascular tissues evaluated by immunohistochemistry for CD34 was significantly higher in the cases with the expression of VEGF-R2 and neuropilin-1 than in those without their expression (P < 0.01), whereas VEGF-R1 expression had no such relationship with the vascular density. The fibrovascular tissues that expressed VEGF165 together with VEGF-R2 and neuropilin-1 were found in significantly younger patients (P < 0.01). In situ hybridization and immunohistochemical studies demonstrated that glial cells in the fibrovascular tissues express and produce VEGF. CONCLUSIONS: Coexpression of VEGF-R2 and neuropilin-1 is suggested to facilitate fibrovascular proliferation in diabetic retinopathy.

Adult↗

[Liposarcoma of the spermatic cord in the left scrotum and inguinal region: a case report].

We report a rare case of liposarcoma of the spermatic cord in the left scrotum and inguinal region. The patient was a 75 year old male, who visited our hospital with the complaint of painless left scrotal swelling and inguinal mass which had been noticed for 3 to 4 years. Ultrasonography and computed tomography (CT) showed a heterogenous mass in the left inguinal region and intrascrotum. We suspected a left testicular tumor and removed it by high inguinal orchiectomy. Histological examination revealed a well-differentiated liposarcoma of sclerosing type. Tumor local recurrence was not recognized at 8 months after operation. This is the 43rd case of liposarcoma of the spermatic cord in the Japanese literature.

Aged↗

[A case of severe stenosis of bilateral distal vertebral artery successfully treated with anastomosis operation].

A 65-year-old male complained of loss of consciousness for several minutes, transient diplopia and dizziness. He had no neurological deficits nor abnormalities in MR imaging. However, flow velocity of bilateral vertebral artery on ultrasonography indicated severe stenosis of bilateral distal vertebral artery. Brain angiography revealed severe stenosis of bilateral distal vertebral artery as well as occlusion of right middle cerebral artery (MCA). Single photon emission CT (SPECT: ECD-RVR method with acetazolamide loading) showed decreased cerebral blood flow and poor perfusion reserve in bilateral cerebellar hemisphere and right MCA territory. Superficial temporal artery-superior cerebellar artery (STA-SCA) anastomosis was performed. The patient turned out to have no episodes of unconsciousness attack, transient diplopia and dizziness after operation. Cerebral blood flow (CBF) in the posterior circulation was also improved. Evaluating quantitative CBF measurement by means of ECD-RVR method was useful for evaluating CBF. In cases who have severe stenosis of bilateral distal vertebral artery with complaints of vertebrobasilar insufficiency, STA-SCA anastomosis may be one of the most effective treatments.

Aged↗

Detection of circulating cancer cells by reverse transcription-polymerase chain reaction for uroplakin II in peripheral blood of patients with urothelial cancer.

Few attempts have been made at the molecular detection of urothelial cancer cells in the blood or lymph nodes mainly because of an absence of good candidate molecular or genetic changes specific to urothelial cancer or urothelium. In 1990, however, genes that encode urothelium-specific transmembrane proteins, uroplakins (UPs), were cloned. We have established a method of detecting circulating cancer cells in peripheral blood of patients with transitional cell carcinoma by nested reverse transcription-PCR assay for UP II. UP II mRNA-positive cells were detected in 3 (10.3%) of 29 patients with superficial cancers (pTa-1N0M0), 4 (28.6%) of 14 patients with muscularly invasive cancers (pT2-4N0M0), 2 (40.0%) of 5 loco-regional node-positive patients (pN1-2M0), and 6 (75.0%) of 8 patients with distant metastases. Positive rates, therefore, increased with tumor extension (P = 0.0033, Kruskal-Wallis test). Furthermore, sequential blood sampling was performed in three patients with metastases during and after systemic chemotherapy, and UP-II-positive cells were found to have disappeared in two patients who responded well to the systemic chemotherapy. These results suggest that our nested reverse transcription-PCR assay for UP II is highly specific and might be used as a tumor marker for molecular staging of urothelial cancers, although the sensitivity is not so optimal.

Adult↗

[The application of poly (L-lactide) sternal coaptation pins for median sternotomy].

Poly (L-lactide) sternal coaptation pin has been developed as an assistant material for the fixation of sternum. We used the novel material to a patient who underwent median sternotomy. A 21-year-old male was suspected to have invasive thymoma in the anterior mediastinum. The median sternotomy was indicated as an approach for the resection of tumor. Tumor was completely resected and there was no invasion to sternum. For the fixation of sternum, three poly (L-lactide) sternal coaptation pins were inserted in the bone marrow of sternum and five stainless steel wires were used as conventional procedure. Sternum was adapted without slippage and no complication from the material was observed in the post-surgical period. The application of poly (L-lactide) sternal coaptation pin is a good option for ensuring the fixation of sternum.

Adult↗

[Present condition of lung transplantation candidates in eastern Japan].

We investigated the present condition of lung transplant candidates and the familiarity of doctors in eastern Japan by questionnaire. We shipped questionnaires to 614 hospitals in the Hokkaido district, the Tohoku district, the Kanto district and Niigata Prefecture, a received responses from 216 departments (200 hospitals). The percentage of respondents was 32.6%. There were 191 lung transplant candidates, 97 men and 94 women, in the past two years. Moreover, there were 45 patients with primary pulmonary hypertension (PPH), 38 with idiopathic pulmonary fibrosis, 23 with pulmonary emphysema, 20 with pulmonary lymphangiomyomatosis, among others. Currently, however, there are 88 patients who are lung transplant candidates, a large number, in eastern Japan. On the other hand, only 38 of 68 departments had informed their patients about lung transplantation. It was a lamentable result for transplant surgeons, and points urgently to the importance of giving information about lung transplantation.

Adolescent↗

[Clinical training and home therapy in our clinic].

Since 1986, we have practiced clinical training. In this training, the physician trainee acts as the head of our clinic, managing programs including the medical teams for outpatient clinics and home therapy. Our home therapy started in 1975 and successive resident trainees have held conferences, cooperation between hospitals and clinics between clinics, and also held home patient and family parties. In our clinical training, therefore, the resident can effectively gain generalized clinical abilities.

Aged↗

Disaster drills and continuous medical education using satellite-based Internet.

We designed and evaluated a satellite-based Internet system for use in medical applications. Many experimental telemedicine projects use satellites, but we combined digital satellite communication with an ordinary telephone network to realize an economical countrywide network for emergency medicine and continuous medical education. The system appears to be a useful and practical technology for daily clinical activities.

Disaster Planning↗

[Brain metastasis of bladder carcinoma after total cystectomy: a case report].

A 74-year-old woman underwent total cystectomy with ureterostomy on March 1993 on a diagnosis of advanced bladder cancer. The pathological diagnosis was transitional carcinoma grade 3, pT3a pN0 pV1, pL2. Two courses of adjuvant chemotherapy with CDDP and MTX were added. Three years and 3 months later, she began to suffer from amnesia and hemiparalysis on her left side. Brain MRI examination revealed a solid tumor, 4 x 4 x 3 cm in size, in the right frontal lobe of the cerebrum. No other metastatic lesions were found. She underwent surgical resection of the tumor and subsequent irradiation to right frontal lobe in the cerebrum. Pathological examination confirmed its origin of bladder cancer. She has been enjoying a disease-free life for 3 years with minimal neurological symptoms.

Aged↗

[Clinical analysis of patients referred for lung transplantation in eastern Japan].

We investigated the indications for lung transplantation (LTx) in Japan and discussed questions regarding the current Japanese criteria of LTx. This study examined 37 patients referred to our institute for LTx. Among these patients, there were 11 cases of primary pulmonary hypertension (PPH), 6 of lymphoangiomyomatosis (LAM), 4 of Eisenmenger's syndrome, 3 of bronchiolitis obliterans, 2 each of bronchiectasis, idiopathic pulmonary fibrosis (IPF), and pneumoconiosis, and 7 of other diseases. The most frequent age group was 30-39 years (12 cases, 32.4%), and more than half of the patients were female (22 cases, 59.5%). The regions of residence of the patients were Tohoku (19 patients), Kanto (16), and Chubu (2). Patients were referred from all over eastern Japan. On evaluation, LTx was contraindicated in 5 cases, in 4 of which mechanical ventilation had been installed before consultation with us. Six patients died before registration on the Japan Organ Transplant Network (JOT). 6 transplant candidates were registered with JOT, but one (PPH) died after 6 months of waiting, and one (LAM) received a lung transplant from a brain dead cadaver donor. We propose to reform and clarify the Japanese criteria for LTx-both indications and contraindications, to include such indications as a survival probability of less than two years, and such contraindications as mechanical ventilation. Early consultation at LTx centers was hoped for, in accordance with the International Guidelines and a transplant window.

Adolescent↗

[Toxicologic screening in Japan].

What we have learned from the Tokyo subway sarin gas attack on March 20, 1995, and the Wakayama poisoned curry incident on July 25, 1998, is that Japanese system for the analysis of drugs and poisons for medical treatment is extremely poor. The frequent occurrence of crimes involving drugs and poisons has become a serious problem. In response, the government established the Countermeasure Committee for Poisonous and Dangerous Substances, which submitted a report in November 1998. Based on that report, the Ministry of Health and Welfare equipped emergency medical centers with expensive analytical instruments, such as high-performance liquid chromatography columns and fluorescence X-ray analyzers, upon request. However, problems in their operation have occurred, and few such facilities work efficiently. In the Wakayama incident, the initial was food poisoning. Only after 11 hours and the deaths of four people was the diagnosis of cyanide poisoning made public. During that process, at least three mistakes were made. We believe that a basic and correct understanding of those mistakes and the development of countermeasures are necessary to analyze drugs and poisons from a medical standpoint.

Drug-Related Side Effects and Adverse Reactions↗