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Biomedical subjects

Osamu Miyake

Publications and source records attributed to Osamu Miyake.

At least 19 recordsLinked to original sources

Renal cell carcinoma in dialysis patients: a single center experience.

AIM: Renal cell carcinoma (RCC) is a life-threatening complication of end-stage renal disease with an unclear pathogenesis. We evaluated RCC developing in patients undergoing dialysis. METHODS: In 2624 patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis at our hospital between July 1993 and March 2004, we performed annual screening for RCC using abdominal computed tomography and ultrasonography. Patients diagnosed with RCC underwent radical nephrectomy as well as clinical and pathologic evaluation. RESULTS: RCC was detected in 44 patients (1.68%; 31 males and 13 females). The age of RCC patients was 55.5 +/- 11.1 years. Dialysis duration before RCC diagnosis was 11.2 +/- 7.2 years. Most RCC were early stage and low stage by TNM classification, 43 patients had N0M0 RCC, whereas one had N1M0. Tumor size was 2.9 +/- 1.9 cm. The predominant histological type of RCC was common or conventional cell-type carcinoma (clear cell carcinoma and granular cell carcinoma). Of patients, 5(11.4%) had bilateral RCC, and satellite tumor lesions in RCC were detected in 13 (29.5%). In 36 patients (81.8%) RCC was accompanied by acquired cystic disease of the kidney. These patients had longer dialysis durations (P = 0.01) and smaller tumors (P = 0.048). RCC metastasized postoperatively in 4 patients (9.1%), while one (2.3%) died of cancer. CONCLUSIONS: Our dialysis patients showed a higher incidence of RCC than the general population. Prognosis was favorable because tumors were detected by screening when they were small. Therefore, periodical screening for RCC seems very important in dialysis patients.

Adult↗

[A case of further significant anastomotic rupture after gentle traction of urethral catheter for minimal anastomotic leakage after radical retropubic prostatectomy].

A 76-year-old man with clinical stage T1c adenocarcinoma of the prostate underwent radical retropubic prostatectomy. After a cystography on postoperative day 7 demonstrated minimal contrast extravasation, gentle catheter traction was performed. However, a cystography on postoperative day 21 showed a displacement of the catheter out of the bladder due to more significant anastomotic rupture. The catheter was preserved without catheter traction for two months. A cystography revealed complete healing of anastomosis without extravasation. This case suggests that catheter traction for anastomotic leakage should be performed carefully because of a potential risk of further anastomotic leakage.

Adenocarcinoma↗

[Pelvic lymph node metastasis from bladder cancer markedly responsive to methotrexate vinblastine doxorubicin and cisplatin (M-VAC) therapy followed by radiotherapy: a case report].

We report a case of bladder cancer with pelvic lymph node metastasis effectively treated by chemotherapy followed by radiotherapy. The patient was a 65-year-old man who had undergone radical cystectomy. Histological findings showed urothelial carcinoma, G3 > G2, pT1b. After 31 months, computerized tomography (CT) revealed a bulky tumor (7.0 x 5.6 cm) along the left pelvic wall, indicating pelvic lymph node metastasis. Five courses of chemotherapy consisting of M-VAC (methotrexate, vinblastine, doxorubicin and cisplatin) was performed. The size of the tumor was reduced to 1.5 x 1.0 cm. Then, external beam radiotherapy (50 Gy) was added to the residual tumor. He has been alive with no evidence of disease progression for 31 months since the radiotherapy.

Aged↗

Retroperitoneoscopic living related-donor nephrectomy: clinical outcomes of 50 consecutive cases and comparison with open donor nephrectomy.

PURPOSE: To determine whether living related retroperitoneoscopic donor nephrectomy (RDN) is a safe and effective procedure. PATIENTS AND METHODS: From September 2001 to May 2004, RDN was performed in 50 consecutive patients at our hospital. All patients were followed longitudinally with office visits. Perioperative and postoperative data for these RDNs, including operative time, blood loss, and complications, were compared with those of open donor nephrectomies (ODNs) performed between January 1999 and December 2001. RESULTS: The RDN was completed in all cases. The average warm ischemia times were 4.1 minutes (range 1.0-8.5 minutes) and 3.5 minutes (range 2.3-5.5 minutes) in the RDN and ODN groups, respectively (P = NS). The mean operative time for RDN was significantly longer than that for ODN (P < 0.001), but patients in the RDN group had significantly shorter hospital stays (P < 0.05). There was no significant difference between the groups in blood loss during operation or number of doses of analgesics administered after the operation. Perioperative and early postoperative complications occurred in 14 patients (28%) in the RDN group and consisted of subcutaneous emphysema in 9, wound infection in 3, and persistent headache in 2 patients. All kidneys removed retroperitoneoscopically functioned immediately. No recipients required post-transplant continuous hemodialysis. CONCLUSIONS: The RDN is a safe and effective procedure for both donor and recipient. Although the benefits of RDN have been demonstrated, further long-term studies of graft function and patient survival are needed.

Adult↗

Urological robotic surgery: preliminary experience with the Zeus system.

AIM: We performed robotic or robotically-assisted laparoscopic surgery for urological diseases, and evaluated the ef ficacy and safety of this surgery. METHODS: Between November 2003 and June 2004, we performed laparoscopic surgery with the Zeus system in eight cases. Three adrenalectomy cases of cortical adenoma presenting with Cushing syndrome and primary aldosteronism, and two cases of nephrectomy for renal cell carcinoma in dialyzed patients were performed solely with Zeus. In two cases of ureteral stenosis, Zeus was used for ureteral anastomosis after partial ureterectomy by manual laparoscopy. In one prostatectomy case, vesico-urethral anastomosis was performed with Zeus after extraperitoneal prostatectomy by manual laparoscopy. RESULTS: All of the cases were successfully treated without any complications during or after operation. All patients were discharged from hospital within 12 days postoperatively. As for adrenalectomy, nephrectomy and pyeloplasty, this may be the fi rst report in Japan. CONCLUSIONS: Our preliminary experiences suggest that such a robot system, which is being developed day by day, might become more beneficial in future in urological laparoscopic surgery.

Adult↗

Primary aldosteronism combined with preclinical Cushing's syndrome in an elderly patient.

Pre-clinical Cushing's syndrome (pre-CS) is sometimes seen with adrenal cortical tumors. An 80-year-old woman had severe hypertension and hypokalemia, the typical clinical features of primary aldosteronism, but detailed hormonal examinations revealed the accompanying pre-CS. After adrenalectomy by laparoscopy, her blood pressure was remarkably reduced and the hypokalemia also recovered. The tumor consisted of mostly light clear cells and scattered dark compact cells resembling islands. Abundant expression of cytochrome P450 aldosterone synthase in the clear cells and cytochrome P450 11beta-hydroxylase in the dark cells was detected by immunohistochemical studies, which confirmed that clear cells can produce aldosterone and compact cells can produce cortisol.

Adrenal Cortex Neoplasms↗

Molecular identification of Sphingomonas sp. A1 alginate lyase (A1-IV') as a member of novel polysaccharide lyase family 15 and implications in alginate lyase evolution.

Sphingomonas sp. A1 (strain A1) produces three endotypes (A1-I [65 kDa], A1-II [25 kDa], and A1-III [40 kDa]) and an exotype (A1-IV [86 kDa]) alginate lyases in cytoplasm. These four enzymes cooperatively depolymerize alginate into constituent monosaccharides. In addition to the genes for these lyases, novel genes encoding hypothetical proteins homologous with A1-IV were found in the genomes of many bacteria including strain A1. One such protein, A1-IV' (90 kDa) of strain A1, was overexpressed in Escherichia coli cells, purified, and characterized. A1-IV' catalyzed the cleavage of glycosidic bonds in alginate through a beta-elimination reaction and released unsaturated di- and trisaccharides as main products, thus indicating that the enzyme is an endotype alginate lyase. A1-IV', which differed from A1-IV in some enzymatic properties, was not expressed in strain A1, suggesting that A1-IV' has no significant role in alginate metabolism. A1-IV' and other A1-IV homologs facilitate the creation of novel polysaccharide lyase family 15 based on their primary structures, implying the evolution route of alginate lyases in family PL-15.

Amino Acid Sequence↗

Structure and function of a hypothetical Pseudomonas aeruginosa protein PA1167 classified into family PL-7: a novel alginate lyase with a beta-sandwich fold.

Structural and functional analyses of alginate lyases are important in the clarification of the biofilm-dependent ecosystem in Pseudomonas aeruginosa and in the development of therapeutic agents for bacterial disease. Most alginate lyases are classified into polysaccharide lyase (PL) family-5 and -7 based on their primary structures. Family PL-7 enzymes are still poorly characterized especially in structural properties. Among family PL-7, a gene coding for a hypothetical protein (PA1167) homologous to Sphingomonas alginate lyase A1-II was found to be present in the P. aeruginosa genome. PA1167 overexpressed in Escherichia coli cleaved glycosidic bonds in alginate and released unsaturated saccharides, indicating that PA1167 is an alginate lyase catalyzing a beta-elimination reaction. The enzyme acted preferably on heteropolymeric regions endolytically and worked most efficiently at pH 8.5 and 40 degrees C. The specific activity of PA1167, however, was much weaker than that of the known alginate lyase AlgL, suggesting that AlgL plays a main role in alginate depolymerization in P. aeruginosa. In addition to this specific activity, differences were found between PA1167 and AlgL in enzyme properties such as molecular mass, optimum pH, salt effect, and substrate specificity. The first crystal structure of the family PL-7 alginate lyase was determined at 2.0 A resolution. PA1167 was found to form a glove-like beta-sandwich composed of 15 beta-strands and 3 alpha-helices. The structural difference between the beta-sandwich PA1167 of family PL-7 and alpha/alpha-barrel AlgL of family PL-5 may be responsible for the enzyme characteristics. Crystal structures of polysaccharide lyases determined so far indicate that they can be assigned to three folding groups having parallel beta-helix, alpha/alpha-barrel, and alpha/alpha-barrel + antiparallel beta-sheet structures as basic frames. PA1167 is the fourth novel folding structure found among polysaccharide lyases.

Amino Acid Sequence↗

Posttranslational processing of polysaccharide lyase: maturation route for gellan lyase in Bacillus sp. GL1.

Cells of Bacillus sp. GL1 extracellularly secrete a gellan lyase with a molecular mass of 130 kDa responsible for the depolymerization of a heteropolysaccharide (gellan), although the gene is capable of encoding a huge protein with a molecular mass of 263 kDa. A maturation route for gellan lyase in the bacterium was determined using anti-gellan lyase antibodies. The fluid of the bacterial exponentially growing cultures on gellan contained two proteins with molecular masses of 260 and 130 kDa, both of which reacted with the antibodies. The 260 kDa protein was purified from the cultured fluid and characterized. The protein exhibited gellan lyase activity and showed similar enzyme properties, such as optimal pH and temperature, thermal stability, and substrate specificity, to those of the 130 kDa gellan lyase. The N-terminal amino acid sequences of the 260 and 130 kDa enzymes were found to be identical. Determination of the C-terminal amino acid of the 130 kDa enzyme indicated that the 260 kDa enzyme is cleaved between the 1205Gly and 1206Leu residues to yield the mature form (130 kDa) of the gellan lyase. Therefore, the mature enzyme consists of 1170 amino acids (36Ala-1205Gly) with a molecular weight of 125,345, which is in good agreement with that calculated from SDS-PAGE analysis. Judging from these results, gellan lyase is first synthesized as a preproform (263 kDa) and then secreted as a precursor (260 kDa) into the medium through cleavage of the signal peptide. Finally, the precursor is post-translationally processed into the N-terminal half domain of 130 kDa as the mature form, the function of C-terminal half domain being unclear.

Amino Acid Sequence↗

Origin and diversity of alginate lyases of families PL-5 and -7 in Sphingomonas sp. strain A1.

Sphingomonas sp. strain A1 has three endotype alginate lyases (A1-I, A1-II [family PL-7], and A1-III [family PL-5]), each of which is encoded by a single gene. In addition to those of these lyases, a gene (the A1-II' gene) showing significant identity with the A1-II gene was present in the bacterial genome and coded for an alginate lyase with broad substrate specificity. Since no expression of A1-II' was observed even in bacterial cells grown on alginate, the A1-II' gene was thought to be a silent gene derived from the A1-II gene, presumably through duplication, modification, and translocation.

Amino Acid Sequence↗

Renal tubular cell injury and fibronectin.

We recently reported that fibronectin (FN: 230 kDa) was oversecreted from the renal tubular cells as a result of the stimulation of COM crystals, and inhibited the adhesion of COM crystals to renal tubular cells. In the study presented here, we investigated whether FN can prevent injury to renal tubular cells caused by oxalate and COM crystals and tried to identify the relation with inhibition of crystal adhesion. The protective effect of FN against renal tubular cell injury by exposure to oxalate and COM crystals was examined by measuring the lactate dehydrogenase (LDH) activity and using a non-radioactive proliferation assay. Moreover, crystal-cell interaction was morphologically assessed by means of scanning electron microscopy (SEM). LDH was reduced significantly by the addition of FN in a dose-dependent manner. Cell viability increased significantly with the addition of FN, also in a dose-dependent manner. Moreover, the morphological SEM study showed that few crystals were attached to the surface of cells when FN was added compared to the number of adhering crystals when FN was not added. FN was found to have an inhibitory effect on renal tubular cell injury caused by exposure to oxalate and COM crystals. We speculate that the inhibitory effect of FN on the adhesion of COM crystals is related to the inhibitory effect of exposure to COM crystals on renal tubular cell injury.

Animals↗

Molecular identification of an alpha-L-rhamnosidase from Bacillus sp strain GL1 as an enzyme involved in complete metabolism of gellan.

The genes (rhaA and rhaB) for two alpha-L-rhamnosidases of Bacillus sp. strain GL1, which assimilates a bacterial polysaccharide (gellan), were cloned from a genomic DNA library of the bacterium constructed in Escherichia coli, and the nucleotide sequences of the genes were determined. Gene rhaA (2661 bp) contained an open reading frame (ORF) encoding a protein (RhaA: 886 amino acids) with a molecular weight (MW) of 98280. Gene rhaB (2871 bp) contained an ORF encoding a protein (RhaB: 956 amino acids) with a MW of 106049. RhaA exhibited significant identity (41%) with alpha-L-rhamnosidase of Clostridium stercorarium, while RhaB showed slight homology with enzymes from other sources. An overexpression system for the two enzymes was constructed in E. coli, and the enzymes were purified and characterized. Both RhaA and RhaB were highly specific for rhamnosyl saccharides, including gellan disaccharide (rhamnosyl glucose) and naringin, and released rhamnose from substrates most efficiently at pH 6.5-7.0 and 40 degrees C. Bacillus sp. strain GL1 cells grown in a gellan medium produced only RhaB, indicating that RhaB plays a crucial role in the complete metabolism of gellan.

Amino Acid Sequence↗

Crystallization and preliminary X-ray analysis of a novel unsaturated glucuronyl hydrolase from Bacillus sp. GL1.

Unsaturated glucuronyl hydrolase from Bacillus sp. GL1 catalyzes the hydrolytic release of unsaturated glucuronic acids from oligosaccharides produced by the reactions of polysaccharide lyases such as gellan, xanthan, hyaluronate and chondroitin lyases. The enzyme was crystallized at 293 K from a droplet containing 56% MPD, 0.1 M NaCl, 0.1 M glycine-NaOH pH 8.2 and 0.1 M dithiothreitol using the vapour-diffusion method. The crystals were hexagonal and belonged to space group P6(1)22 or P6(5)22, with unit-cell parameters a = b = 102.8, c = 223.4 A. Diffraction data to 2.4 A were collected from a single crystal.

Bacillus↗

An exotype alginate lyase in Sphingomonas sp. A1: overexpression in Escherichia coli, purification, and characterization of alginate lyase IV (A1-IV).

Sphingomonas sp. A1 (strain A1) cells contain three kinds of endotype alginate lyases [A1-I, A1-II, and A1-III], all of which are formed from a common precursor through posttranslational processing. In addition to these lyases, another type of lyase (A1-IV) that acts on oligoalginates exists in the bacterium. A1-IV was overexpressed in Escherichia coli cells through control of its gene under the T7 promoter. The expression level of the enzyme in E. coli cells was 8.6U/L-culture, which was about 270-fold higher than that in strain A1 cells. The enzyme was purified to homogeneity through three steps with an activity yield of 10.9%. The optimal pH and temperature, thermal stability, and mode of action of the purified enzyme were similar to those of the native enzyme from strain A1 cells. A1-IV exolytically degraded oligoalginates, which were produced from alginate through the reaction of A1-I, A1-II, or A1-III, into monosaccharides, indicating that the cooperative actions of these four enzymes cause the complete depolymerization of alginate in strain A1 cells.

Alginates↗

Infected urachal cyst ruptured during medical palliation.

Since most cases of urachal cyst are asymptomatic, they are frequently detected after complication by infection. Ruptured urachal cysts are frequently detected after complication by severe infections such as sepsis. We report on a 31-year-old man who was diagnosed preoperatively as having an infected urachal cyst and the decision was made to follow the patient because primary excision was scheduled to be performed a few days later. Symptoms were transiently relieved, but the cyst ruptured during medical palliation. We treated this case with a two-stage surgical procedure.

Adult↗

Adult Wilms' tumor mimicking hemorrhagic renal cyst.

A 36-year-old man presented with macroscopic hematuria associated with right flank pain. Examination of the patient revealed a cystic mass in the right kidney. Because the mass had increased in size, enucleation of the mass was performed. Histopathological findings revealed nephroblastoma, therefore, radical nephrectomy was performed. We believe the pathogenesis of the cystic formation to be a process in which a tumor that had developed in the pericalyceal region spontaneously ruptured, exuding urine into the perinephric space, forming a cystic mass. The patient is alive with no evidence of disease 24 months after the operation.

Adult↗

Experience with laparoscopic splenectomy for ABO-incompatible living related renal transplantation.

PURPOSE: To determine whether laparoscopic splenectomy for ABO-incompatible living related renal transplantation is safe and effective. PATIENTS AND METHODS: From July 2000 to May 2002, laparoscopic splenectomy was performed on the day of transplantation in 10 patients undergoing ABO-incompatible living related renal transplantation. Perioperative and postoperative data, including operative time, blood loss, and complications, were evaluated. RESULTS: The mean operative time was 79 minutes. Intraoperative blood loss ranged from 25 mL to 600 mL (mean 130 mL). Transfusion was not required in any case. One patient required open conversion because of bleeding from the splenic hilum. The serum amylase value was slightly elevated postoperatively in four patients but normalized with conservative treatment. One patient had bleeding from a trocar port wound, which was likewise treated conservatively. No complications, including postoperative renal dysfunction or fatal infections, that were considered attributable to the laparoscopic procedure were noted. CONCLUSIONS: Laparoscopic splenectomy performed simultaneously with renal transplantation is a safe and efficacious procedure for ABO-incompatible living related renal transplantation.

ABO Blood-Group System↗