Biomedical subjects

K Yoshimura

Publications and source records attributed to K Yoshimura.

At least 163 records · Page 9Linked to original sources

PubMed1998

High urinary excretion level of citrate and magnesium in children: potential etiology for the reduced incidence of pediatric urolithiasis.

It is well known that the incidence of calcium oxalate (CaOX) urolithiasis is much lower in children than in adults [2, 21]. One purpose of this study was to compare the inhibitory activity on CaOX crystal growth and nucleation of urine from children (ufC) with that of urine from adults (ufA). Another was to measure low molecular weight urinary substances related to CaOX lithiasis, including citrate and magnesium, which have been identified as stone inhibitors. The excretion volume per body weight of uric acid, phosphorus, magnesium and citrate was all significantly higher in 24-h ufC than in 24-h ufA, but that of calcium and oxalate was not. The growth inhibitory activities against CaOX crystals of ufC and ufA were measured in a whole urine system. The diameter of the crystals produced in this system was smaller for ufC (3.68 microm) than for ufA (4.66 microm). We also examined the metastable limit for CaOX with fresh spot urine, which was 3.15 mmol/l in ufC and 0.41 mmol/l in ufA. These results indicate that ufC has a more powerful inhibitory effect on CaOX crystal growth and nucleation than ufA. We also found that the excretion rate of citrate and magnesium in ufC was much higher than in ufA. We suggest that these two stone inhibitors are very likely to elevate the inhibitory activity of ufC against CaOX crystal growth and nucleation. The lower incidence of CaOX lithiasis in children might thus be partly attributed to citrate and magnesium.

Adult↗

PubMed1998

Arterial reconstruction: justified for patients with intermittent claudication?

The objective of this study was to evaluate the effects of arterial reconstruction in patients with intermittent claudication. A total of 243 patients (305 limbs) underwent lower extremity vascular reconstruction at our institution from 1979 to 1995. They were assessed by physical examination, pulse volume recordings, segmental pressure, Duplex ultrasonography, and intravenous subtraction arteriography to evaluate the effects of arterial reconstruction. Surviving patients (220 limbs) were enrolled for evaluation of outcome during the follow-up period. There were 59 deaths during the follow-up period. The cumulative life-table 5-year patency rates were 90% +/- 3%, 73% +/- 6%, and 74% +/- 10% for aortoiliac, infrainguinal, and aortofemorodistal arterial reconstructions, respectively. Among 129 repairs in the aortoiliac region, Fontaine stages I, II, and III were found in 109 limbs (84.5%), 17 limbs (13.2%), and 2 limbs (1.5%), respectively. There was one (0.7%) minor amputation. There was Fontaine stage I in 50 limbs (76.9%), Fontaine stage II in 14 limbs (21.5%), and Fontaine stage III in 1 limb (1.5%) for repairs in the infrainguinal region. Among the 26 aortofemorodistal repairs, there was Fontaine stage I in 21 limbs (81%) and Fontaine stage II in 5 limbs (19%). There was a statistically significantly higher incidence of Fontaine stage I than Fontaine stage II or III in aortofemoral, infrainguinal, and aortofemorodistal arterial reconstructions (p < 0.0001). Arterial reconstruction for patients at Fontaine stage II offered benefits and improved quality of life at follow-up. Arterial reconstruction for patients at Fontaine stage II offers benefits and improved quality of life at follow-up. It was concluded that the significant improvement in quality of life after arterial reconstruction warrants continued use of the procedure in patients with intermittent claudication.

Adult↗

PubMed1998

The role of CD4+ and CD8+ T-cells in host morbidity and innate resistance to angiostrongylus cantonensis in the mouse.

Strain-dependent differences in host morbidity and mortality due to Angiostrongylus cantonensis infection have been established between C57BL/6 and BALB/c mice; C57BL/6 mice show rapid worm killing with low morbidity, whereas BALB/c mice indicate slow worm killing with high morbidity and mortality. To determine the possible roles of CD4+ and CD8+ T-cells in host morbidity and innate resistance to A. cantonensis infection we treated C57BL/6 and BALB/c mice with anti-CD4 or anti-CD8 monoclonal antibody and examined the changes in host morbidity and worm-killing activity. Our study indicates that anti-CD4 antibody treatment interferes with worm killing and improves the morbidity of A. cantonensis-infected BALB/c mice, whereas anti-CD8 antibody treatment fails to improve the morbidity. Tumor necrosis factor-alpha (TNF-alpha, or cachectin) production in infected mice was not correlated with host morbidity. Anti-IL-5 monoclonal antibody treatment also failed to affect the morbidity of infected BALB/c mice, although their worm-killing activity was restrained as shown in anti-CD4-treated mice. These findings clearly indicate that the morbidity of infected BALB/c mice is regulated by some unknown CD4+ T-cell-dependent mechanism but not by an IL-5-, eosinophil-, or TNF-alpha-dependent mechanism.

Angiostrongylus cantonensis↗

PubMed1998

Negative association between asthma and variants of CC16(CC10) on chromosome 11q13 in British and Japanese populations.

The gene encoding Clara cell-derived inflammatory molecule CC16 has been cited as a candidate gene for atopic asthma on chromosome 1lq13. A genetic association study was performed with variants of the CC16 gene on chromosome 1lq13 in relation to asthma in British (n=275) and Japanese (n=300) populations. No significant association was found between asthma and CC16 genotypes, irrespective of atopic status in these two populations. These data suggest that CC16 might not be the major locus for asthma on 11q13.

Asthma↗

PubMed1998

Purification and characterization of ascorbate peroxidase in Chlorella vulgaris.

Chlorella vulgaris contained only one isoform of ascorbate peroxidase (AsAP) as the hydrogen peroxide (H2O2)-scavenging system except for catalase at a specific activity of 3.3 +/- 0.2 units/mg protein. The activity of glutathione peroxidase was not detected in the extracts from cells grown in the absence and presence of sodium selenite. We detected the activity of monodehydroascorbate reductase involved in the regeneration of ascorbate, but we failed to detect the dehydroascorbate reductase activity. AsAP has been purified to electrophoretic homogeneity from Chlorella cells. The enzyme was a monomer with a molecular mass of 32 kDa using gel filtration and SDS-polyacrylamide gel electrophoresis. The enzyme showed higher specificity with ascorbate than with pyrogallol. The K(m) values of the enzyme for ascorbate and H2O2 were 111 +/- 8.9 and 20 +/- 2.5 microM, respectively. When the enzyme was diluted with the ascorbate-deleted medium, the half inactivation time was approximately 15 min. The absorption spectra of the purified enzyme and the inhibition by cyanide and azide showed that it is a hemoprotein. The enzyme was markedly inhibited by 0.2 mM p-chloromercuribenzoate. The enzyme cross-reacted by immunoblotting with the monoclonal antibody raised against Euglena cytosolic AsAP. The amino acid sequences in the N-terminal region of Chlorella AsAP showed no significant similarity to any other AsAPs from higher plants and algae.

Amino Acid Sequence↗

PubMed1998

A case of poliomyelitis-like syndrome.

The authors report the case of a boy aged 4 years who had sudden abdominal pain and inability to walk on the day before admission to hospital and who developed abdominal distention and difficulty urinating. On admission, the abdominal skin reflexes, knee jerks, cremaster and anal reflexes were absent and power in the lower extremities was reduced. Spinal fluid examination showed a cell count of 383/mm3, with 95% neutrophils and 5% lymphocytes; spinal fluid protein of 44 mg/dl; and glucose 75 mg/dl. Serological studies did not reveal any significant antibodies for polio virus type 1, 2, 3, various ECHO viruses, Coxsackie types A4, A7, A9, B1 or B5. However, the titer of Coxsackie virus antibody type A10 was 128 in the acute phase and only 32 in the recovery phase 4 weeks later. Magnetic resonance scans were performed on the second day; the findings were normal in the brain, but interesting lesions were revealed in the thoracic cord with both T1-weighted images and T2-weighted images. Neurological symptoms improved asymmetrically.

Child, Preschool↗

PubMed1998

Focal pachypolymicrogyria in three siblings.

The malformation of focal pachypolymicrogyria might be the manifestation of an X-linked recessive disorder according to the results of this study. Three siblings revealed focal pachypolymicrogyria on magnetic resonance imaging (MRI) and had a strong family history of epilepsy and mental retardation. All three siblings had the same mother; the father of Patient 1 was not related to the mother, but the father of Patients 2 and 3 was related to her. The MRI of the father of Patients 2 and 3 demonstrated focal pachypolymicrogyria. The mother's MRI was normal. In this family, epilepsy or mental retardation was found mainly in the males (Patient 3 was an exception), and they were all born to female members of this family, not male. Patient 3 was probably a homozygote with an X-linked recessive inheritance, and therefore, she demonstrated the most severe clinical findings.

Adolescent↗

PubMed1998

Analysis of T cell populations and IL-3 mRNA expression in mesenteric lymph node cells and intestinal intraepithelial lymphocytes in Strongyloides ratti-infected mice.

T cell populations and IL-3 mRNA expression were analysed in mesenteric lymph node cells and intestinal intraepithelial lymphocytes (IEL) in Strongyloides ratti-infected mice. On days 7 and 12 post-infection, 2.6 times as many mesenteric lymph node cells were present in S. ratti-infected mice compared with uninfected mice. Although the percentages of CD3+, CD4+ and CD8+ cells decreased during infection, the absolute numbers of these cell types increased on day 7 due to an overall increase in the mesenteric lymph node cell number. The CD4/CD8 ratio in IEL was increased on day 5, whereas no significant change in the CD4/CD8 ratio was observed in the mesenteric lymph node cells. Expression of IL-3 mRNA, which is an important cytokine for the induction of murine mucosal mastocytosis and S. ratti-expulsion, was examined in mesenteric lymph nodes and IEL of uninfected and infected mice. IL-3 mRNA was detected in mesenteric lymph nodes of S. ratti-infected mice but not detected in the lymph nodes of uninfected mice. IL-3 mRNA was detected in IEL from both infected and uninfected mice with an 20-fold increase in expression in IEL of infected mice. Overall, IL-3 mRNA levels were higher in IEL than in mesenteric lymph nodes following S. ratti-infection. Expression of IL-4, IL-10, stem cell factor (SCF or c-kit ligand) and IFN-gamma mRNA was also examined in these two tissues. IL-10 mRNA was not detected in any tissue examined and IFN-gamma mRNA levels were unaltered as a result of an S. ratti-infection. Elevated expression of mRNA for SCF (5-fold) and IL-4 (20-fold) was observed in the mesenteric lymph nodes of infected mice. In contrast, SCF mRNA levels were similar in IEL of uninfected and infected animals and only a modest increase in IL-4 mRNA was observed in IEL of infected mice.

Animals↗

PubMed1998

Expression of Tamm-Horsfall protein in stone-forming rat models.

OBJECTIVES: To examine the expression of Tamm-Horsfall protein (THP) and calcium oxalate deposition in three rat models to clarify whether THP plays an active role in crystal formation or whether crystals induce the secretion of this protein. MATERIALS AND METHODS: A stone-forming rat model (model 1) with marked tubular dilatation in an entire kidney was produced by rendering Wistar rats (aged 8 weeks) hyperoxaluric and hypercalciuric, through compulsorily feeding with 0.12 mL of 5% ethylene glycol (in two doses daily) and 0.5 microgram of vitamin D3 every other day. Two other rat models were also produced. Model 2 comprised stone-forming rats with minimal tubular dilatation, achieved by giving rats the same dose of ethylene glycol once daily, and model 3 comprised stone-free rats with marked tubular dilatation achieved by unilateral ureteric ligation. The rats' kidneys were resected after 4 weeks and all resected kidneys immunohistochemically stained with an antibody to THP. Simultaneously, the location of calcium oxalate (CaOx) crystals was established with von Kossa staining. The relation between crystals and the secretion of THP was also assessed in vitro. Cultured renal epithelial cells (NRK-52E) were stained with an antibody to THP after they had been cultured for 72 h in a medium containing CaOx crystals. RESULTS: In model-1 kidneys with both tubular dilatation and many crystals, there was local and intense expression of THP in many renal tubules. CaOx crystals and the intense expression of THP tended to occur in the same renal tubules. In model 2 kidneys with little tubular dilatation, only a few renal tubules expressed THP strongly and the location of the crystals rarely coincided with that of THP expression. In model 3 kidneys with marked tubular dilatation but no crystals, THP was expressed strongly in many renal tubules. The expression of THP in cultured NRK-52E cells was not stimulated by CaOx crystals. CONCLUSIONS: The results from the in vivo models suggest that THP did not initiate crystal formation and the strong expression of THP was induced not by crystals but by renal tubular damage caused by tubular dilatation. From the close association of THP and crystals in model 1 kidneys, this protein might play a secondary role as an adhesive, promoting stone formation.

Adjuvants, Immunologic↗

PubMed1998

Use of the disposable stapler to insure proper fixation of a transferred muscle in treatment of facial paralysis.

The authors introduce the use of a disposable stapler to create a stable muscle end in transferring a free neurovascular muscle segment for the treatment of facial paralysis. This procedure allows the firm fixation of the fragile soft end of a muscle transferred to the nasolabial region of a paralyzed face, and avoids adhesion and tethering of the muscle end to the skin, which may result in inaccurate positioning of a newly-created nasolabial fold and an asymmetrical smile. Transection and hemostasis at both ends of the harvested muscle segment also can be achieved simultaneously. Although the disposable stapler incurs additional cost, it can greatly improve the result of a free neurovascular muscle transfer for the treatment of facial paralysis, as well as simplify harvesting of the muscle segment. No complications and problems have been encountered in stapling the muscle.

Disposable Equipment↗

PubMed1998

Comparison of clinical outcomes of laparoscopic and conventional open adrenalectomy.

From September 1992 to November 1996, 28 patients underwent laparoscopic adrenalectomy at Osaka University Medical Hospital. They were compared with 25 instances of conventional open surgery performed between May 1990 and April 1996 at the same institution. Laparoscopic adrenalectomy was performed via either a transperitoneal or a retroperitoneal approach. The mean operative time of 375 minutes for laparoscopic adrenalectomy was significantly longer than that of 133 minutes for open surgery. The average hospital stay for laparoscopic surgery was significantly shorter than that of conventional open adrenalectomy. The convalescent period was also significantly shorter in the patients who had laparoscopic adrenalectomy. There was no statistical difference in blood loss during the operation or the number of doses of analgesics administered after operation in the two groups. We conclude that laparoscopic adrenalectomy is one of the options to be selected in surgically managing adrenal tumors. Laparoscopic adrenalectomy could become a standard operative procedure as instruments and techniques of laparoscopy improve significantly.

Adolescent↗

PubMed1998

Molecular characterization and physiological role of a glyoxysome-bound ascorbate peroxidase from spinach.

cDNAs encoding two cytosolic and two chloroplastic ascorbate peroxidase (AsAP) isozymes from spinach have been cloned recently [Ishikawa et al. (1995) FEBS Lett. 367: 28, (1996) FEBS Lett. 384: 289]. We herein report the cloning of the fifth cDNA of an AsAP isozyme which localizes in spinach glyoxysomes (gAsAP). The open reading frame of the 858-base pair cDNA encoded 286 amino acid residues with a calculated molecular mass of 31,507 Da. By determination of the latency of AsAP activity in intact glyoxysomes, the enzyme, as well as monodehydroascorbate (MDAsA) reductase, was found to be located on the external side of the organelles. The cDNA was overexpressed in Escherichia coli (E. coli). The enzymatic properties of the partially purified recombinant gAsAP were consistent with those of the native enzyme from intact glyoxysomes. The recombinant enzyme utilized ascorbate (AsA) as its most effective natural electron donor; glutathione (GSH) and NAD(P)H could not substitute for AsA. The substrate-velocity curves with the recombinant enzyme showed Michaelis-Menten type kinetics with AsA and hydrogen peroxide (H2O2); the apparent Km values for AsA and H2O2 were 1.89 +/- 0.05 mM and 74 +/- 4.0 microM, respectively. When the recombinant enzyme was diluted with AsA-depleted medium, the activity was stable over 180 min. We discuss the H2O2-scavenging system maintained by AsAP and the regeneration system of AsA in spinach glyoxysome.

Amino Acid Sequence↗

PubMed1998

One-stage transfer of the latissimus dorsi muscle for reanimation of a paralyzed face: a new alternative.

The two-stage method combining neurovascular free-muscle transfer with cross-face nerve grafting is now a widely accepted procedure for dynamic smile reconstruction in cases with long established unilateral facial paralysis. Although the results are promising, the two operations, about 1 year apart, exert an economic burden on the patients and require a lengthy period before obtaining results. Sequelae such as hypoesthesia, paresthesia, and conspicuous scar on the donor leg for harvesting a sural nerve graft also cannot be disregarded. To overcome such drawbacks of the two-stage method, we report a refined technique utilizing one-stage microvascular free transfer of the latissimus dorsi muscle. Its thoracodorsal nerve is crossed through the upper lip and sutured to the contralateral intact facial nerve branches. Reinnervation of the transferred muscle is established at a mean of 7 months postoperatively, which is faster than that of the two-stage method. In our present series with 24 patients, 21 patients (more than 87 percent) believed that their results were excellent or satisfactory, which also compares well with the results of the two-stage method combining free-muscle transfer with cross-face nerve graft.

Adolescent↗

PubMed1998

Incidence of lymph node metastasis and its impact on long-term prognosis in clinically localized prostate cancer.

BACKGROUND: Pelvic lymph node dissection (PLND) is an important staging method for men with clinically localized prostate cancer. We report our experience with staging PLND and the impact of lymph node metastasis on long-term prognosis. METHODS: One hundred forty-eight consecutive patients who underwent staging PLND for clinically localized prostate cancer were retrospectively studied. Patients were evaluated for the presence and number of lymph node metastases, treatment (prostatectomy vs. radiotherapy), and endocrine therapy, and analyzed with respect to disease progression and survival. The mean follow-up period was 52.9 months (range, 2.3 to 165.8 months). RESULTS: Thirty-two patients (21.6%) had pelvic lymph node metastases, the incidence of which markedly decreased from 32.3% in 1982 to 1987 to 6.7% in 1994 to 1997. The intervals to disease progression and cancer death were significantly shorter in patients with positive lymph nodes (P < 0.001). In stage D1 disease, patients who underwent a radical prostatectomy tended to be free of progression longer than those receiving radiotherapy or conservative therapy (P = 0.0546). Other factors, such as early endocrine therapy, the extent of lymph node involvement and the Gleason score of the primary tumor did not predict disease progression or survival. CONCLUSION: These data suggest a decreasing trend in the incidence of lymph node metastasis in the PSA era. Although longer disease-free intervals were observed in radical prostatectomy-treated patients, the impact of an aggressive approach to stage D1 disease awaits further studies.

Adenocarcinoma↗

PubMed1998

Long-term results of definitive treatment in elderly patients with localized prostate cancer.

BACKGROUND: The indication and effectiveness of definitive local treatment for prostate cancer in patients with a limited life expectancy remains to be established. This study is a retrospective analysis of the long-term clinical outcome of elderly patients with localized prostate cancer treated by radiotherapy or a radical prostatectomy. METHODS: From 1982 to 1992, 37 patients with localized prostate cancer, aged 70 years or older, were treated initially by a pelvic lymphadenectomy and then with either external radiotherapy (n = 1 7) or a radical retropubic prostatectomy (n = 20). Lymph node metastasis was negative in all the cases, and no patients received hormonal treatment after the lymphadenectomy. The outcome of all patients was evaluated in June 1997. RESULTS: The 10-year overall and relative survival rates for the radiotherapy group were 27% and 85%, which were not significantly different from the rates of patients in the prostatectomy group (38% and 74%, respectively). The 5-year progression free rates for the radiotherapy group and the prostatectomy group were 63% and 95%, respectively (P= 0.06). CONCLUSION: In elderly patients with localized prostate cancer, the superiority of a radical prostatectomy over radiotherapy was not demonstrated in terms of either overall or relative survival rates, although the progression rate tended to be higher in patients in the radiotherapy group. The indication of definitive treatment in elderly patients should be further studied incorporating a quality of life assessment.

Aged↗

PubMed1998

[A case of bacillary dysentery caused by new quinolone-resistant Shigella flexneri 2a].

A 73-year-old male was admitted to our hospital because of detection of Shigella flexneri 2a from his stool. Antimicrobial treatment with levofloxacin (LVFX) was started, but could not eliminate the organism in the stool. In the examination of drug susceptibility, this strain was highly resistant to all new quinolones. The minimal inhibitory concentration of norfloxacin, ofloxacin and ciprofloxacin to this strain was 12.5 micrograms/ml, 6.25 micrograms/ml and 6.25 micrograms/ml, respectively. The dual mutations were detected in the codon 83 and 87 of the gyrA gene by sequencing the quinolone-resistance determining region (QRDR). There was, however, no significant difference between the intracellular uptake of ciprofloxacin in this strain and in the ciprofloxacin-sensitive strain. The amount of ciprofloxacin in this strain unchanged when carbonyl cyanide m-chlorophenyl hydrazone (CCCP) was added. These results suggest that the advanced resistance in Shigella flexneri against new quinolones could be acquired by only this dual mutations without the change of the active efflux mechanism.

4-Quinolones↗

PubMed1998

Investigation of the possible role of sialic acid in calcium oxalate urolithiasis.

OBJECTIVE: It is considered that sialic acid in urine comprises two different types of sialic acid, that is, the free sialic acid and the bound one which exists as a basic component of urinary macromolecules. The present studies were performed to clarify the role of sialic acid in urine and compare the excretion and concentrations of sialic acid in urine between calcium oxalate (CaOx) stone formers and healthy subjects. METHODS: First, we prepared the crystal surface binding substances from whole human urine. The crystal surface binding substances were digested with sialidase and both the inhibitory activity on CaOx crystal growth and concentrations of sialic acid before and after sialidase digestion were measured. The inhibitory activity of free sialic acid in ultrafiltered urine was also measured. The excretion and concentration of sialic acid in urine from patients with CaOx urolithiasis and healthy controls were determined and compared. RESULTS: The inhibitory activity of crystal surface binding substances on CaOx crystal growth did not show any significant difference before and after sialidase digestion. The free sialic acid had also no effect on CaOx crystal growth. There was no statistically significant difference between CaOx stone formers and healthy controls on the excretion and concentration of sialic acid in urine. The free:bound sialic acid ratio in urine was considered 1:0.97 and 1:1.33 for healthy controls and CaOx stone formers respectively (p = NS). CONCLUSIONS: It is suggested that neither the free sialic acid nor the bound one in urine has a significant inhibitory effect on CaOx crystal growth.

Calcium Oxalate↗

PubMed1998

Laparoscopic adrenalectomy. Comparison of the transperitoneal and retroperitoneal approach.

OBJECTIVES: The efficacy of transperitoneal (TP) and retroperitoneal (RP) laparoscopic adrenalectomy was compared. METHODS: Twenty-nine patients (male: 13; female: 16) with benign adrenal tumor were evaluated in this study. Seventeen were treated with the TP, and 12 with the RP approach. RESULTS: Convalescence for the TP group took longer than that for the RP group and postoperative pain was stronger for the TP than the RP group, although the difference was not significant. In addition, the amount of blood loss was larger for the TP than the RP group. When the cases were divided according to site of disease, the operating time for the right side was 351 min for the TP group and 347 min for the RP group, while that for the left side was 528 min for the TP group and 267 min for the RP group. CONCLUSIONS: Therefore, we recently prefer the RP approach for left adrenalectomy, but consider either approach suitable for the right side. The reason for this preference is that shortening the operating time is most important, also in the case of laparoscopic adrenalectomy because of the resulting reduced blood loss and the patients' early convalescence.

Adolescent↗