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Biomedical subjects

S Miyoshi

Publications and source records attributed to S Miyoshi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Thymic carcinoma successfully resected with superior vena cava after chemoradiotherapy.

A 57-year-old woman hospitalized for thymic cancer invading the superior vena cava and left brachiocephalic vein evidenced both pleural and pericardial effusion. After chemotherapy with cisplatin and docetaxel and concurrent radiotherapy, the entire tumor was successfully resected along with the pericardium, superior vena cava, and left brachiocephalic vein, followed by vascular reconstruction. Pathologically, viable tumor cells were identified only in the center of the tumor as anaplastic cell carcinoma. Induction chemoradiotherapy thus appears useful in enabling complete resection of advanced thymic carcinoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

An analysis of video-assisted thoracoscopic resection for mediastinal masses in 150 cases. An overview of the pansternal approach, histology, and complications.

BACKGROUND: To clarify the usefulness of the diagnosis and treatment of mediastinal masses, by video-assisted thoracoscopic surgery (VATS), we performed a retrospective multi-institutional study to delineate the type of approach, histopathology, and complications associated with these entities. METHODS: We analyzed 150 patients who underwent the VATS procedure at several institutions between 1991 and 1999. RESULTS: VATS resections were performed using various combinations of the "pansternal approach." The unilateral thorax approach was applied in 135 patients, the bilateral thorax approach combined with the suprasternum approach in seven patients, the unilateral thoracic approach combined with the supraclavicular approach in three patients, the infrasternal approach in three patients, and the bilateral thoracic approach combined with both the infrasternal and the suprasternal approaches in two patients. Thoracoscopic resections or biopsies diagnosed 140 benign and 10 malignant mediastinal masses. There were operative complications in nine patients (6%). Eight patients (5.3%) were converted to conventional thoracotomy. CONCLUSION: VATS is a safe, effective, minimally invasive technique that can facilitate the resection of mediastinal masses when the pansternal approach is applied as appropriate for the location of the tumor.

Adolescent↗
PubMed2001

The C-terminal domain promotes the hemorrhagic damage caused by Vibrio vulnificus metalloprotease.

Vibrio vulnificus, an opportunistic human pathogen, produces a 45-kDa zinc metalloprotease (V. vulnificus protease; VVP) as an important virulence determinant. VVP injected intradermally into the dorsal skin causes the hemorrhagic damage through specific degradation of type IV collage in the vascular basement membrane. The N-terminal 35-kDa polypeptide (VVP-N), the catalytic domain, also evoked the hemorrhagic skin reaction within minutes. However, the hemorrhagic activity of VVP-N was one-third of that of VVP. Besides, the proteolytic activity of VVP-N toward the reconstituted basement membrane or type IV collagen was found to be about 50 % of VVP. VVP-N, like VVP, was quickly inactivated by an equimolar amount of alpha(2)-macroglobulin, a broad-spectrum plasma protease inhibitor. These findings indicate that the C-terminal 10-kDa polypeptide, the substrate-binding domain mediating the effective binding to protein substrates, functions to augment the hemorrhagic reaction of VVP.

Amino Acid Sequence↗
PubMed2001

Recovery of electrophysiological parameters after conversion of atrial fibrillation.

We investigated the recovery of electrophysiological parameters from electrical remodeling after conversion of chronic lone atrial fibrillation in humans. Clinical studies have shown that the longer atrial fibrillation lasts, the more difficult it becomes to maintain the sinus rhythm after cardioversion. To explore the effects of the duration of atrial fibrillation on changes of electrophysiological parameters after conversion, we determined the atrial effective refractory period and P wave duration during right atrial pacing at 1 and 24 h after electrical cardioversion in 15 patients with chronic lone atrial fibrillation (median duration, 6 months). By 24 h after cardioversion, the effective refractory period at a pacing cycle length of 600 ms increased from 225+/-19 to 254+/-27 ms. However, the P wave duration did not decrease significantly 24 h after conversion. As the duration of atrial fibrillation became longer, the prolongation of effective refractory period was more delayed (P<0. 001, r=0.82), and the shortening of P wave duration was significantly smaller within 24 h after cardioversion (P<0. 001, r=0.67). After cardioversion of chronic lone atrial fibrillation, the recovery of shortened atrial refractoriness and prolonged intraatrial conduction time is dependent on the duration of preexisting atrial fibrillation.

Atrial Fibrillation↗
PubMed2001

Evaluation of the efficacy and safety of laparoscopic nephrectomy.

PURPOSE: To evaluate the efficacy and safety of laparoscopic nephrectomy. METHODS: From June 1994 to November 1999, 10 patients underwent laparoscopic nephrectomy at Osaka University Medical Hospital and Osaka Rosai Hospital. Laparoscopic nephrectomy was performed either via transperitoneal or retroperitoneal approach under general anesthesia. These 10 cases were reviewed in respect of primary disease of the kidney, operative time, complications and postoperative convalescence. RESULTS: Of the 10 patients, five were preoperatively diagnosed as having a non-functioning kidney with hydronephrosis, two patients were diagnosed as having an atrophic kidney, two had renal cell carcinoma and one had renal pelvic tumor. The average operative time was 374 min (range 270-675 min). The mean blood loss was 330 mL (range 60-800 mL). One patient required transfusion due to postoperative oozing. The average hospital stay after operation was 7 days. No major postoperative complications were observed. CONCLUSION: Laparoscopic nephrectomy is an option in surgically managing renal disorders, including malignancies, although it has a longer operative time compared to conventional open surgery.

Adult↗
PubMed2001

Clinical and functional significance of WHO classification on human thymic epithelial neoplasms: a study of 146 consecutive tumors.

We examined the clinical and functional significance of histologic classification of thymic epithelial neoplasms proposed by the World Health Organization (WHO), based on an analysis of 146 consecutive tumors derived from 141 patients and 47 normal thymuses derived from children ranging in age from 1 to 9 years. Invasive tumors were seen in 12.5%, 38.6%, 40.0%, 69.4%, 80.0%, and 100% of type A, AB, B1, B2, B3, and C primary tumors, respectively. All of six recurrent or metastatic lesions were type B2 tumors. Myasthenia gravis was associated in 0%, 6.8%, 40.0%, 55.6%, 10.0%, and 0% in patients with type A, AB, B1, B2, B3, and C tumors, respectively. The average number (x10(6)) of tumor-associated CD4+CD8+ cells present in 1 g of tumor tissue was 1.5, 391.1, 1041.7, 333.9, 24.5, and 0.2 in type A, AB, B1, B2, B3, and C, respectively, and it was 1168.2 in the normal thymuses. Thus, type B1 tumor retained the function to induce CD4+CD8+ double-positive cells at a level comparable to that of the normal thymic cortical epithelial cells, followed by type AB and type B2 tumors. Type A and B3 tumors had this function at a barely detectable level, and type C tumor was nonfunctional. WHO histologic classification was shown to reflect the clinical features and the T-cell-inducing function of thymic epithelial tumors.

CD4-CD8 Ratio↗
PubMed2001

Electropharmacologic effects of pilsicainide, a pure sodium channel blocker, on the remodeled atrium subjected to chronic rapid pacing.

Clinical experience suggests that sodium channel blockers are effective in converting atrial fibrillation of recent onset but not chronic atrial fibrillation. We investigated changes in the electrophysiologic effects of pilsicainide, a pure sodium channel blocker, on the canine atrium during chronic rapid pacing (400/min). Three pairs of bipolar electrodes were sutured to the right atrial appendage in six dogs. Five days later, rapid atrial pacing was started after baseline measurements of the effective refractory period (ERP), the intra-atrial conduction velocity, the atrial wavelength, and the inducibility of atrial fibrillation. These studies were repeated at 2, 7, and 14 days of pacing, both before and after pilsicainide administration. Before pacing, pilsicainide increased ERP more than it decreased conduction velocity, causing an increase of wavelength, particularly at faster rates. However, this use-dependent prolongation of ERP disappeared after 2 days of pacing. Thus, pilsicainide failed to prolong ERP during chronic pacing, allowing progressive shortening of wavelength in the remodeled atrium. The effect of sodium channel blockers on atrial refractoriness may decline as rapid atrial excitation persists, limiting the usefulness of these agents for the treatment of chronic atrial fibrillation.

Animals↗
PubMed2001

Identification and characterization of the sodA genes encoding manganese superoxide dismutases in Vibrio parahaemolyticus, Vibrio mimicus, and Vibrio vulnificus.

Sequencing of Fur titration assay-positive clones obtained from genomic DNA libraries of Vibrio parahaemolyticus, V. mimicus and V. vulnificus revealed open reading frames encoding proteins of 202, 205 and 202 amino acid residues, respectively. Each open reading frame was preceded by a predicted Fur box which overlaps a likely promoter with similarity to the -10 and -35 consensus sequence of Escherichia coli. The deduced amino acid sequences shared considerable homology with bacterial Mn-containing superoxide dismutases (MnSODs). Consistent with this, these Vibrio strains produced proteins with SOD activity resistant to inhibition by H2O2 and KCN only when grown under iron-limiting conditions. Primer extension analysis of the total RNA from these vibrios revealed iron-repressible expression of the genes. Furthermore, when grown under iron-limiting conditions, E. coli carrying a plasmid with each cloned gene overexpressed protein with the same electrophoretic mobility and insensitivity of SOD activity to H2O2 and KCN. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by N-terminal amino acid sequencing revealed that proteins (MnSODs) having N-terminal amino acid sequences consistent with those deduced from the corresponding genes were present in cell lysates of the vibrios grown under these iron-limited conditions. These results demonstrate that the genes cloned in this study are sodA homologs encoding MnSODs, whose expression is regulated by the iron status of the growth medium. PCR using a primer set based on the V. parahaemolyticus sodA sequence revealed the presence of homologous genes in certain other Vibrio species.

Amino Acid Sequence↗
PubMed2001

Analysis of seawaters for the recovery of culturable Vibrio parahaemolyticus and some other vibrios.

We investigated the recovery of dormant and injured cells along with the normally culturable cells of Vibrio species with special emphasis on V. parahaemolyticus using both selective and non-selective media at moderate (20 C) and standard (37 C) culture temperatures from a bay water environment. Culture temperatures (20 or 37 C) did not affect the recovery of V. parahaemolyticus but did for other vibrios. We observed similar seasonality of V parahaemolyticus as in most other environmental studies. V. parahaemolyticus and other Vibrio species were recovered in higher numbers by a replica plating method compared to most probable number (MPN) and direct TCBS (thiosulfate citrate bile-salt sucrose) agar counts. Even with the replica plating method, however, vibrios number goes down to a minimum level and V. parahaemolyticus was undetectable during the cool temperature period of the year, although total bacterial cells and CFU on nutrient agar (with 2% NaCl) did not vary so much during the study period.

Colony Count, Microbial↗
PubMed2001

[A case of urothelial tumors which occurred simultaneously in bilateral upper urinary tracts and bladder presenting with anuria].

A 72-year-old male was admitted with a chief complaint of anuria. Clinical examinations showed that he was in uremic state and had bilateral hydronephroses. An endoscopic examination revealed a left ureteral tumor and a bladder tumor. Left nephroureterectomy with partial cystectomy and transurethral resection of the bladder tumor were performed. Pathological examinations showed an invasive left renal pelvic tumor (pT3, G3), an invasive left ureteral tumor (pT4, G3), and a bladder tumor (pTis, G3). Following the operation, roentgenological and urinary cytological findings showed a right ureteral carcinoma. He died of multiple liver and bone metastases and local recurrence at 5 months postoperatively.

Aged↗
PubMed2001

[Transitional cell carcinoma of the bladder in a young patient: a case report].

A 14-year-old male patient was admitted with the chief complaint of macroscopic hematuria. Abdominal ultrasonography demonstrated a tumor of the anterior wall of the bladder. Further, cystoscopic examination confirmed a papillary tumor. Transurethral resection of the bladder tumor was performed. Histopathology of the excised tumor showed transitional cell carcinoma (G1, pTa). Recurrence has not been observed for 9 months postoperatively.

Adolescent↗
PubMed2001

[Undescended testicular tumor found by torsion of the testis: a case report].

A 37-year-old man was admitted with a painful mass in his left inguinal region. He had an undescended testis on the left side. Six months earlier, he had noted that his left inguinal testis was larger, and he had suddenly developed pain in the left inguinal region. The levels of AFP, hCG beta and LDH were normal. We diagnosed a left undescended testicular tumor and torsion of the left testis. Left inguinal high orchiectomy showed a torsion of the left testis and histopathological examination of the specimen revealed seminoma.

Adult↗
PubMed2001

[Renal metastasis originating from pulmonary carcinoma: a case report].

A 61-year-old woman, who had undergone total right pneumonectomy 22 months before due to lung cancer (adenosquamous cell carcinoma) was admitted for macroscopic hematuria. Abdominal CT showed two renal tumors in the right kidney. Right radical nephrectomy was performed, because no imaging study showed any other metastasis. Pathological examination revealed adenosquamous cell carcinoma, which was the same pathology as the lung cancer had been. She died of the left lung metastasis 24 months after right radical nephrectomy. Her prognosis was thought to have been prolonged by the operation of right radical nephrectomy.

Carcinoma, Adenosquamous↗
PubMed2001

[Late metastases of prostatic adenocarcinoma to urinary bladder after radical prostatectomy: a case report].

We report a case of metastasis of prostatic cancer to urinary bladder. A 67-year-old man was admitted with a complaint of macroscopic hematuria, who had undergone radical prostatectomy and surgical castration for prostatic cancer (pT3N0M0) 53 months before. Computed tomographic (CT) scan revealed an invasive tumor on the right wall of the urinary bladder and swelling of paraaortic and pelvic lymph node metastases. These lesions were diagnosed as bladder tumor with lymph node metastases, and then transurethral biopsy of bladder tumor was performed. Because macroscopic hematuria could not be controlled and severe progressive anemia was found after the biopsy, simple cystectomy and bilateral cutaneoureterostomy were performed on the next day. Histopathological analysis showed that the tumor was adenocarcinoma, which was thought to be a metastatic tumor from the prostatic cancer.

Adenocarcinoma↗
PubMed2001

[Prostatic carcinoma presenting as neck lymph node metastases: report of two cases].

We report two cases of prostatic carcinoma presenting as neck lymph node metastases. Case 1: A 56-year-old man was admitted to our hospital with the chief complaint of left lower abdominal pain. A lymph node was palpable on the left side of the neck swollen. Rectal examinations revealed prostatic stony-hard mass. Computed tomography showed a swollen neck and paraaortic lymph nodes on the left side. PSA level was 380 ng/ml. Transperineal prostatic biopsy revealed moderately differentiated adenocarcinoma, and neck lymph node biopsy also revealed metastatic adenocarcinoma. We diagnosed him with prostatic carcinoma stage D2 (LYM). He underwent hormonal therapy (TAB) but died 13 months later. Case 2: A 66-year-old man was admitted to our hospital with the chief complaint of a large palpable mass on the left side of the neck. Resection of this mass revealed metastatic adenocarcinoma. Rectal examination revealed no malignant lesions, but the PSA level was high, 1,700 ng/ml. Transperineal prostatic biopsy revealed moderately differentiated adenocarcinoma. Computed tomography revealed paraaortic and pelvic lymph node metastases and bone scintigram revealed abnormal uptake, bone metastases. We diagnosed him with prostatic carcinoma stage D2 (LYM OSS). We performed bilateral testectomy followed by hormonal therapy (TAB). The lymph node metastases disappeared after 4 months of therapy.

Adenocarcinoma↗
PubMed2001

[A case of multiple emphysematous bullae treated with living-donor lung transplantation from identical twin brothers].

A 30-year-old man with multiple emphysematous bullae and bronchiectasis was admitted to Toyama Medical and Pharmaceutical University Hospital because of exertional dyspnea and fever. His chest radiograph and CT scan revealed multiple large bullae in the right lung and infiltrative shadows in the left middle lung field. Pseudomonas aeruginosa was isolated from his sputum culture. Although standard therapies including various antibiotics were administered, his respiratory condition was exacerbated, accompanied with the enlargement of bullae in the right lung and the consequent shift of the mediastinum to the left. The patient and his family proposed lung transplantation, and we concluded that lung transplantation would be an appropriate treatment for his disease. We transported the patient to Osaka University Hospital. Living-donor lung transplantation from the patient's identical twin brothers was successfully performed.

Adult↗
PubMed2000

Calmodulin kinases II and IV and calcineurin are involved in leukemia inhibitory factor-induced cardiac hypertrophy in rats.

We recently reported that leukemia inhibitory factor (LIF) enhances Ca(2+)](i) through an increase in L-type Ca(2+) current (I(Ca,L)) in adult cardiomyocytes. The aim of this study was to investigate whether LIF activates Ca(2+)-dependent signaling molecules, such as calcineurin and calmodulin kinases II and IV (CaMKII and CaMKIV), and, if so, whether these Ca(2+)-mediated signaling events contribute to LIF-mediated cardiac hypertrophy. We first confirmed that LIF increased I(Ca,L) and [Ca(2+)](i) in primary cultured rat neonatal cardiomyocytes. Calcineurin, CaMKII, and CaMKIV activities increased at 2 minutes and peaked by 1.6-, 2.2-, and 2.2-fold, respectively, at 15 minutes. Nicardipine or verapamil fully inhibited these activities. Autophosphorylation of CaMKII was also observed to parallel the timing of CaMKII activity, and this phosphorylation was blocked by nicardipine, verapamil, or EGTA. LIF treatment led to a 3-fold increase in nuclear factor of activated T cell-luciferase activity. To confirm that inositol triphosphate (IP(3))-induced Ca(2+) release from sarcoplasmic reticulum was not involved in this process, IP(3) content and phosphorylation of phospholipase Cgamma were investigated. LIF did not increase IP(3) content or phosphorylate phospholipase Cgamma. KN62 (an inhibitor of CaMKII and CaMKIV) attenuated c-fos, brain natriuretic peptide, alpha-skeletal actin, and atrial natriuretic peptide expression. KN62 suppressed the LIF-induced increase in [(3)H]phenylalanine uptake and cell size. Cyclosporin A and FK506 slightly attenuated brain natriuretic peptide but did not affect c-fos or atrial natriuretic peptide expression. Cyclosporin A significantly reduced the LIF-induced increase in [(3)H]phenylalanine uptake. These findings indicated that LIF activated CaMKII, CaMKIV, and calcineurin through an increase in I:(Ca,L) and [Ca(2+)](i) and that CaMKII, CaMKIV, and calcineurin are critically involved in LIF-induced cardiac hypertrophy.

Aniline Compounds↗