Biomedical subjects

T Hatano

Publications and source records attributed to T Hatano.

At least 19 recordsLinked to original sources

PubMed2000

Microaerobic hydrogen production by photosynthetic bacteria in a double-phase photobioreactor.

The rate of hydrogen production by the marine nonsulfur photosynthetic bacterium, Rhodovulum sp., increased with increasing light intensity. A light intensity of 1800 W/m(2) hydrogen production rate was achieved at the rate of 9.4 micromol/mg dry weight/h. The hydrogen production of this strain was enhanced by the addition of a small amount of oxygen (12 micromol O(2)/reactor). Intracellular ATP content was most efficiently accumulated under microaerobic, dark conditions. Hydrogen production rate by Rhodovulum sp. was investigated using a double-phase photobioreactor consisting of light and dark compartments. This rate was compared with data obtained using a conventional photobioreactor. Rhodovulum sp. produced hydrogen at a rate of 0.38+/-0.03 micromol/mg dry weight/h under microaerobic conditions using the double-phase photobioreactor. The hydrogen production rate was four times greater under microaerobic conditions, as compared with anaerobic conditions using either type of photobioreactor. Hydrogen production using a double-phase photobioreactor was demonstrated continuously at the same rate for 150 h.

Adenosine Triphosphate↗

PubMed2000

Restoration of effectiveness of beta-lactams on methicillin-resistant Staphylococcus aureus by tellimagrandin I from rose red.

We found that extract from petals of Rosa canina L. (rose red) strikingly reduced the minimum inhibitory concentration of beta-lactams in methicillin-resistant Staphylococcus aureus. We isolated two compounds that reduced the minimum inhibitory concentrations of beta-lactams from the extract, tellimagrandin I and rugosin B. Tellimagrandin I was very effective regarding the reduction of the minimum inhibitory concentration, and rugosin B showed some effect. Tellimagrandin I showed a weak bactericidal action when added together with oxacillin. Judging from the fractional inhibitory concentration index, the effect of tellimagrandin I and oxacillin was synergistic. Tellimagrandin I also significantly reduced the minimum inhibitory concentration of tetracycline in some strains of methicillin-resistant Staphylococcus aureus.

Anti-Bacterial Agents↗

PubMed2000

Bladder-pumping therapy for the treatment of low-capacity or low-compliance bladders.

The walls of low-capacity or low-compliance bladders are thought to be less elastic than normal. Pumping of the bladder was found to disrupt collagen-fiber bundles in the rat bladder wall, offering the promise of potential clinical application. This result prompted us to use bladder-pumping therapy to soften the bladder wall in patients with low-capacity or low-compliance bladders to restore bladder elasticity. CO(2) gas or air, at a volume below the maximum bladder capacity (</=200 mL), was repeatedly pumped in and out of the bladder through a catheter under caudal anesthesia in 26 patients with low-capacity or low-compliance bladders and without uninhibited bladder contractions, who presented with urinary frequency or incontinence. A respirator was used to control the pumping at 0.5 cycles/s for a duration of 15 minutes. No serious adverse effects were encountered during or after the procedure. Overall subjective improvement was noted 4 weeks after the procedure in 11 of 18 patients with a low capacity bladder (<300 mL) and in five of eight patients with a low-compliance bladder (<20 mL/cm H(2)O). The procedure significantly increased the maximum bladder capacity, single voided volume, and average urinary flow rate after 4 weeks. In the responding patients, subjective improvement lasted from 3 months to over 6 years. Bladder-pumping therapy is an easy and safe procedure and exerts a beneficial effect for a long period, in patients with low-capacity or low-compliance bladders and without uninhibited bladder contractions. Neurourol. Urodynam. 19:19-28, 2000.

Adolescent↗

PubMed2000

Recovery of Bacillus thuringiensis from marine sediments of Japan.

Marine sediments from a Japanese bay were examined for the occurrence of Bacillus thuringiensis. Of 1313 colonies belonging to the Bacillus cereus/B. thuringiensis group, 22 (1.7%) were allocated to B. thuringiensis. Marine isolates of B. thuringiensis consisted of heterogeneous multiple H serogroups; 10 isolates were assigned to the eight serovars (kurstaki, sumiyoshiensis, sotto, aizawai, darmstadiensis, thompsoni, neoleonensis, and higo); two motile isolates failed to react with the reference antisera; and the others were serologically untestable. Insecticidal activities were associated with two kurstaki isolates (toxic to both Lepidoptera and Diptera) and a higo isolate (Diptera-specific). None of the parasporal inclusion proteins of the 22 isolates exhibited in vitro cytotoxic activity against two vertebrate cells, sheep erythrocytes and HeLa cells. All B. thuringiensis isolates had no halophilism, although seawater-based medium supported their growth, sporulation, and formation of parasporal inclusions.

Antigens, Bacterial↗

PubMed2000

Galloylglucoses and riccionidin A in Rhus javanica adventitious root cultures.

Adventitious root cultures of Rhus javanica L. produced large amounts of galloylglucoses (gallotannins) and an anthocyanidin, riccionidin A, formerly found only in liverworts. Production of both galloylglucoses and riccionidin A in the adventitious root culture system was suppressed by light. The Rhus root culture showed the highest productivity for those secondary metabolites in a modified Linsmaier-Skoog (LS) liquid medium containing 30 mM NH4+ and 30 mM NO3- as nitrogen sources in the presence of 10(-6) M 3-indoleacetic acid (IAA).

Anthocyanins↗

PubMed2000

Cytotoxic activity of hydrolyzable tannins against human oral tumor cell lines--a possible mechanism.

Hydrolyzable tannins showed higher cytotoxic activity against human oral squamous cell carcinoma and salivary gland tumor cell lines than against normal human gingival fibroblasts, whereas gallic acid, a component unit of tannins, showed much weaker selective cytotoxicity. The cytotoxic activity of dimeric compounds was generally higher than that of monomeric compounds. Macrocyclic ellagitannin oligomers, such as oenothein B, woodfordin C and woodfordin D showed the greatest cytotoxic activity, and their activity (per given number of molecules) was one order higher than those of gallic acid and epigallocatechin gallate, a major component of green tea. These compounds induced apoptotic cell death characterized by DNA fragmentation (as demonstrated by the TUNEL method) and cleavage of cytokeratin 18 by activated caspase(s) (as demonstrated by M30 monoclonal antibody). ESR spectroscopy revealed that these macrocyclic compounds at higher concentrations produced their own radicals and significantly enhanced the radical intensity of sodium ascorbate, possibly by their prooxidant actions. Catalase failed to eliminate their apoptosis-inducing activity, reducing the possibility of the involvement of hydrogen peroxide production in the extracellular fraction. These observations suggested that the antitumor activity of macrocyclic ellagitannin oligomers reported previously might be explained by their apoptosis-inducing activity.

Antineoplastic Agents↗

PubMed2000

Effects of tannins and related polyphenols on superoxide-induced histamine release from rat peritoneal mast cells.

The effects of tannins and related polyphenols on KO2- and compound 48/80-induced histamine release from rat peritoneal mast cells were examined. Pretreatment with hydrolyzable tannins (1-100 microM) significantly inhibited KO2-induced histamine release. Dimeric ellagitannins, which have hexahydroxydiphenoyl (HHDP) and valoneoyl residues and/or a valoneoyl-related acyl unit in the molecule, showed more potent inhibitory effects than monomeric hydrolyzable tannins. The most effective inhibition was exhibited by agrimoniin and euphorbin C (IC50 0.68 and 0.80 microM), which have dehydrodigalloyl and euphorbinoyl groups, respectively, as well as the HHDP group. However, procyanidins, flavonoids and related polyphenols with small molecular weights, except for epigallocatechin gallate, exhibited negligible effects. Although clinically used antiallergic drugs, azelastine, astemizole, ketotifen and epinastine have been shown to prevent KO2-induced histamine release, their potencies were all less than those of ellagitannins. An inhibitory effect on compound 48/80-induced histamine release was also exhibited by higher molecular weight tannins. The inhibitory effect on histamine release caused by different stimulants suggested that ellagitannins act as cell membrane stabilizers as well as radical scavengers.

Animals↗

PubMed2000

Successful transplantation of a cadaveric kidney with post-infectious glomerulonephritis.

This report describes a successful renal Tx in a patient with chronic renal failure, caused by dysplastic kidneys, who received a cadaveric kidney with post-infectious glomerulonephritis. Sequential renal biopsies were performed at 12 h before Tx, and at 1 h and on days 8 and 58 post-Tx. Post-operative hematuria disappeared on day 9 and proteinuria on day 13. Normal graft function was observed within 1 month, with histologic resolution. Our study suggests that while the donor kidney facilitates deposition of certain immune reactants, this is a host (environmental) problem and when transplanted into a new host (new environment), the problem is no longer sustained.

Adolescent↗

PubMed2000

Pelvic congestion syndrome caused by inferior vena cava reflux.

We present a female patient who had pelvic congestion syndrome caused by inferior vena cava reflux associated with tricuspid regurgitation, but without other symptoms or signs related to her tricuspid regurgitation. Bladder pumping therapy was effective in improving her symptoms.

Female↗

PubMed2000

Impact of citrate therapy on the circadian rhythm of urinary magnesium ammonium phosphate saturation in normal individuals.

BACKGROUND: Alkaline citrate has been used widely in the prevention of stone formation. However, the risk of struvite stone during the alkalinizing therapy has not been adequately studied in terms of magnesium ammonium phosphate saturation. METHODS: The circadian rhythm of the urinary saturation of magnesium ammonium phosphate was estimated by using the differential Gibbs' free energy values of magnesium ammonium phosphate before and during 5 days of treatment with sodium-potassium citrate (1 g t.i.d., 1 g q.i.d. or 3 g t.i.d.) in five healthy male volunteers. RESULTS: The magnesium ammonium phosphate saturation varied during the day, peaking far below the solubility product between 08.00 and 10.30 h and between 13.00 and 18.00 h. The mean peak levels were increased by each treatment regimen in comparison with the control day. The mean increase on day 1 was significant between 10.30 and 23.00 h with the 3 g t.i.d. regimen, but the mean saturation still remained below the solubility product throughout the day. CONCLUSIONS: The urinary magnesium ammonium phosphate saturation appeared hard to exceed the solubility product with a high dose of alkaline citrate.

Adult↗

PubMed2000

Incidence of bone fracture in patients receiving luteinizing hormone-releasing hormone agonists for prostate cancer.

OBJECTIVE: To investigate the incidence of bone fractures in patients receiving luteinizing hormone-releasing hormone agonists (LHRH-a) for prostate cancer (in whom a continued low testosterone level after the long-term administration of these drugs reduces bone mineral density), and thus determine the risk of secondary osteoporosis. PATIENTS AND METHODS: Between 1994 and 1999, 218 patients (mean age 77.3 years) were treated for >/= 6 months with LHRH-a for prostate cancer; of these, 14 (6%) had a bone fracture during their treatment. Patients with fracture associated with motor vehicle accidents were excluded. The bone density in the third lumbar vertebra was meas-ured using quantitative computed tomography. Osteocalcin, 1,25-(OH)2 vitamin D, urinary type 1 collagen cross-linked N-telopeptides (NTx), parathyroid hormone and calcitonin were measured as metabolic markers. RESULTS: The mean age of the patients with fracture was 78 years; the mean (range) interval from the start of treatment to fracture was 28 (11-46) months. There was no case of a bone fracture at the site of a metastasis from prostate cancer. The bone density was significantly lower in the patients with a fracture than in those without. Of the bone metabolic markers, NTx was higher in those with a fracture. CONCLUSION: There is a need to measure bone mineral density and bone metabolic markers periodically, and to evaluate secondary osteoporosis in patients receiving long-term LHRH-a for prostate cancer.

Aged↗

PubMed2000

Apoptosis of mouse embryonic stem cells induced by single cell suspension.

Embryonic stem cells (ES cells) are pluripotential, and are therefore used to construct gene knock-out mice. We found that the apoptosis of mouse ES cells was induced when the cells were dispersed as single cells, whereas this process was suppressed when they proliferated in aggregates. The apoptosis of ES cells was repressed when the cells were cultured on feeders prepared from STO cells, a cell line established from embryonic fibroblasts. Culture supernatants from STO cells did not block the apoptosis of ES cells, which suggests that a direct interaction between ES cells and STO cells is required for the suppression of apoptosis. The viability of ES cells examined by the trypan blue exclusion test or by the MTT ((3-4,5-dimethyithiazol-2-yl)-2,5-diphenyltetrazolium bromide) reduction assay decreased dramatically when the cells were dispersed in phosphate-buffered saline PBS. Cellular activity was restored by the addition of culture medium for ES cells. Glucose in the medium was found to be a major factor responsible for the restoration. Amino acids also restored the decrease in reduction of MTT. Suspension of the ES cells in PBS(-) caused leakage of the nucleosome into cytoplasm. Results indicate that the single cell suspension of ES cells leads to leakage of substrates for oxidative phosphorylation from the mitochondria, and that these cells finally become committed to apoptosis.

Amino Acids↗

PubMed2000

Phenolic constituents of licorice. VIII. Structures of glicophenone and glicoisoflavanone, and effects of licorice phenolics on methicillin-resistant Staphylococcus aureus.

Two new phenolic compounds, glicophenone (1) and glicoisoflavanone (2), were isolated from commercial licorice, and their structures were elucidated on the basis of spectroscopic data. Antibacterial assays of licorice phenolics for Staphylococcus aureus, including four strains of methicillin-resistant S. aureus (MRSA), and also for Escherichia coli K12 and Pseudomonas aeruginosa PAO1, were then examined. Two compounds among them, 8-(gamma,gamma-dimethylallyl)-wighteone (21) and 3'-(gamma,gamma-dimethylallyl)-kievitone (28), showed remarkable antibacterial effects [minimum inhibitory concentrations (MICs), 8 microg/ml on the MRSA strains and methicillin-sensitive S. aureus. Licochalcone A (14), gancaonin G (20), isoangustone A (24), glyasperins C (30) and D (31), glabridin, (32), licoricidin (33), glycycoumarin (34) and licocoumarone (40) showed antibacterial effects on the MRSA strains with MIC values of 16 microg/ml. Effects on the beta-lactam resistance of the MRSA strains were also examined, and licoricidin (33) noticeably decreased the resistance of the MRSA strains against oxacillin, as shown by the reduction in the MICs of oxacillin (lower than 1/128-1/1000 in the presence of 8 microg/ml of 33, and 1/8-1/32 in the presence of 4 microg/ml of 33). Mechanistic study suggested that 33 does not inhibit the formation of penicillin-binding protein 2' (PBP2'), but affects the enzymatic function of PBP2'.

Glycyrrhiza↗

PubMed2000

Polyphenols from Eriobotrya japonica and their cytotoxicity against human oral tumor cell lines.

Three new flavonoid glycosides, together with 15 known flavonoids, have been isolated from the leaves of Eriobotrya japonica, and characterized as (2S)- and (2R)-naringenin 8-C-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosides, and cinchonain Id 7-O-beta-D-glucopyranoside, respectively, based on spectral analyses including two dimensional (2D) NMR techniques. Higher proanthocyanidin fraction in the water-soluble portion of the extract was characterized as a procyanidin oligomer mixture mainly composed of undecameric procyanidin. These polyphenols have also been assessed for cytotoxic activity against two human oral tumor (human squamous cell carcinoma and human salivary gland tumor) cell lines. Selective cytotoxicity of the procyanidin oligomer between tumor and normal gingival fibroblast cells, and its possible mechanism, were also described.

Antibodies, Monoclonal↗

PubMed2000

[Bone fracture receiving LH-RH agonists for prostatic cancer].

BACKGROUND: Luteinizing hormone-releasing hormone (LHRH) agonists are popularly used drugs in the treatment of prostatic cancer. However, it has been reported that continuation of a low testosterone level following a longterm administration of these drugs reduces the bone mineral density and makes for osteoporosis, which is accountable for fracture, we measured the bone mineral density and bone metabolic markers in the cases who suffered fracture receiving LHRH agonists for prostatic cancer. PATIENTS AND METHODS: Between 1994 and 1998, 196 patients (mean age 78.1 years) were treated with LHRH agonists for prostatic cancer. Of these patients, 13(7%) who had bone fracture during treated with LHRH agonists were divided into fracture group, and 70 patients who had not bone fracture divided into non-fracture group. Fracture by traffic accident was excluded. The bone density in the third lumbar vertebra was measured using quantitative computed tomography (QCT). Osteocalcin, 1, 25- (OH)2 vitamin D, urinary type 1 collagen cross-linked N-telopeptides (NTx), parathyroid hormone (PTH) and calcitonin were measured as bone metabolic markers. RESULTS: The mean age of fractured cases was 78 years. The period from the start of treatment to fracture was 11 to 45 months (mean 27 months). No case of fracture at the site of metastasis of prostatic cancer was found. The bone density was significantly low in the fracture group compared with that of non-fracture group. Of the bone metabolic markers, NTx showed high values in the fracture group. CONCLUSION: There is a need to measure bone mineral density and bone metabolic markers periodically and to evaluate secondary osteoporosis in the patients receiving LHRH agonists for prostatic cancer.

Aged↗

PubMed2000

Compensatory renal hypertrophy and changes of renal function following nephrectomy.

We studied the changes in the serum creatinine level and the volume of the remaining kidney following nephrectomy using contrast-enhanced compounded tomogram (CT) scans. Twenty-five patients undergoing nephrectomy for renal cell carcinoma without obvious disease in the remaining kidney were carefully followed for a period of at least two years at our hospital. Twelve patients received follow-up CT scans each year after nephrectomy. The ellipsoid volume of the kidney was calculated by measuring the 3-dimensional size on CT scans. The mean relative volume (%) of the remaining kidney increased up to year 3 postoperatively, and the final mean relative volume at varying periods from years 2 to 7 was 120%. Kidneys that were smaller prior to nephrectomy showed a tendency to have a larger final relative volume after nephrectomy, although there was no significant correlation between the kidney volume prior to nephrectomy and at final measurement. The mean serum creatinine level was significantly increased at one year after nephrectomy, but it decreased significantly over time. Therefore, both compensatory renal hypertrophy and improved renal function seemed to be established within several years after nephrectomy. However, the improvement of serum creatinine was delayed compared with the increase of kidney volume. That is, renal plasma flow might be increased early by compensatory renal hypertrophy, followed within a few years by an increase in glomerular filtration and a decrease of serum creatinine.

Adult↗

PubMed2000

Retroperitoneoscopic heminephrectomy of the right upper collecting system emptying into an ectopic ureterocele in a 5-year-old girl: a case report.

A 5-year-old girl with a history of recurrent urinary tract infection since the age of 14 months was diagnosed as having a right duplicated urinary collecting system with the upper ureter ectopically opening in the urethra. She underwent retroperitoneoscopic heminephrectomy for a right dysplastic kidney and open ureterocelectomy and reimplantation of the refluxing lower ureter via Pfannenstiel incision. She survived the procedure without serious complications and resumed normal daily activities by day 6. To the best of our knowledge, this case is the 16th case of laparoscopic heminephrectomy for pediatric patients and the first case treated by the retroperitoneal approach in the English literature.

Child, Preschool↗

PubMed2000

[A case of metachronous adenocarcinoma of the urinary bladder and the right upper urinary tract].

Bilateral hydronephrosis identified by a local physician brought a 65-year-old man to our hospital. Emergency percutaneous nephrostomy was bilaterally established for obstructive renal failure. After recovering renal function, the patient underwent radical cystectomy under the diagnosis of invasive bladder cancer and the construction of an ileal conduit. The pathology reported well differentiated adenocarcinoma (pT2, pL1, pV1). Five years after the surgery, gross hematuria developed. A computed tomographic scan revealed right hydronephrosis with a solid mass in the upper calyx. The urinary cytology was negative. The patient underwent right nephrectomy in May, 1999. The pathology then revealed well differentiated adenocarcinoma in the renal pelvis and ureter (pT3, pL0, pV0 and pT1, pL0, pV0, respectively). He is alive with mild chronic renal insufficiency with evidence of tumor at ten months after surgery. To our knowledge, this is the first case of metachronous adenocarcinoma of the urinary bladder and the upper urinary tract reported in the Japanese literature.

Adenocarcinoma↗