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S Kawakami

Publications and source records attributed to S Kawakami.

At least 91 records · Page 5Linked to original sources
PubMed2000

[Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyo University Hospital--the second report].

We studied the high-level resistant to cefotaxime (CTX, MIC > or = 512 micrograms/ml) clinical isolates of Escherichia coli and Klebsiella pneumoniae in Teikyo University Hospital. The CTX-resistance could be transferred to E. coli K-12 chi 1037 or ML4903 strains from 30 of the 33 isolates by conjugation at a frequency of 10(-4). When the hydrolysis rate of benzylpenicillin was 100%, the beta-lactamases which were extracted from the transconjugants hydrolyzed CTX, CAZ and AZT at the rate of 38-95%, 0-8.6% and 0-56%, respectively. These results demonstrate that these enzymes should be categorized into ESBL. The nucleotide sequence of CTX-resistant gene was identified to that of the CTX-M2 gene which was first described in Argentina. It was found to have 99.9% homology to Toho-1 gene in Japan and 99.6% homology to CMY-2 gene. Using a PCR methods for the detection of one of ESBL gene such as CTX-M2, Toho-1 or CMY-2, the DNA was amplified from all strains (11 isolates of E. coli and 21 isolates of K. pneumoniae).

Cefotaxime↗
PubMed2000

Characteristics of small lung cancers invisible on conventional chest radiography and detected by population based screening using spiral CT.

Conventional chest radiography (CXR) is a poor diagnostic tool for detecting lung cancers at a surgically curable stage. To determine the visibility of peripheral small lung cancers on CXR, we retrospectively examined the usefulness of CXR using a consecutive series of 44 cases detected on CT screening and later confirmed by histopathology. All cases had been detected by low dose CT during a population based screening trial for lung cancer. The control group consisted of 48 chest radiographs of normal subjects. Tumour diameters ranged from 6 mm to 45 mm, with 95% (42/44) < or = 20 mm, and 5% (2/44) > 20 mm. CXR failed to detect 77% (34/44) of all cancers, including 79% (33/42) < or = 20 mm and 50% (1/2) > 20 mm. Of the 42 lung cancers < or = 20 mm, 74% (31/42) were located in the well penetrated lung zones and 71% (22/31) of these were missed on CXR. 26% (11/42) were concealed by hilar vessels, mediastinum, heart or diaphragm, and all (11/11) of these were missed on CXR. 93% (39/42) of the lung cancers < or = 20 mm were adenocarcinomas and 79% (31/39) of these were missed on CXR. 7% (3/42) were epidermoid carcinomas or small cell carcinomas and 66% (2/3) of these were missed on CXR. The overall accuracy of interpretation on CXR for lung cancers was 61%, sensitivity was 23% and specificity 96%. Although there was an association between presence of lung cancer and positive reading of CXR (chi 2 test of association, p < 0.05), the percentage of positive readings was only 23%. Thus, CXR was poor at visualizing CT detectable lung cancers of < or = 20 mm diameter, which are usually of very low density, and cannot be relied upon for detection of surgically curable small lung cancer.

Adenocarcinoma↗
PubMed2000

Rapidly growing small peripheral lung cancers detected by screening CT: correlation between radiological appearance and pathological features.

12 peripheral small lung cancers (< 20 mm) of rapid growth (volume doubling time < 150 days), detected by repeated low dose CT screening, were evaluated to examine their CT features and to correlate such features with histopathological findings. Each patient's CT images, including follow-up and thin section CT images, were studied retrospectively to determine tumour growth rate and CT morphological features. Nine of the tumours exhibited a solid tumour growth pattern: seven of these showed a well defined, homogeneous, soft tissue density with spicular or lobulated margin. These seven tumours included small cell lung cancer (n = 3), moderately differentiated adenocarcinoma (n = 2), poorly differentiated adenocarcinoma (n = 1) and squamous cell carcinoma (n = 1). The other two tumours, a moderately differentiated adenocarcinoma and a well differentiated adenocarcinoma, appeared as irregular, soft tissue density nodules with poorly defined margins. The latter exhibited an air bronchogram pattern and a small cavity. The remaining three tumours exhibited a lepidic tumour growth pattern. They showed ground glass opacity or ground glass opacity with a higher density central zone on CT images and were well differentiated adenocarcinomas. In conclusion, most peripheral small lung cancers of rapid growth were adenocarcinomas. They also included small cell lung cancer and squamous cell carcinoma. The majority showed solid tumour growth pattern and lacked an air bronchogram and/or small air spaces in the nodule. Some well differentiated adenocarcinomas with lepidic tumour growth pattern also showed rapid growth.

Adenocarcinoma↗
PubMed2000

Targeted delivery of prostaglandin E1 to hepatocytes using galactosylated liposomes.

Prostaglandin E(1) (PGE(1) ) was incorporated in galactosylated liposomes containing cholesten-5-yloxy-N-(4-((1-imino-2-beta-D-thiogalactosyle thyl)amino)b utyl)formamide (Gal-C4-Chol) intended for hepatocyte-selective delivery. Liposomes composed of distearoylphosphatidylcholine (DSPC)/cholesterol (Chol)/Gal-C4-Chol (60&ratio;35&ratio;5) were prepared and compared with DSPC/Chol (60&ratio;40) liposomes. After intravenous injection of [(3) H]-labeled PGE(1) or cholesteryl hexadecyl ether (CHE) with the liposomal formulation, mice were sacrificed at a series of times, and the radioactivity in tissues was determined. Up to about 80% of [(3) H]CHE in galactosylated liposomes had accumulated in the liver 10 min after intravenous injection and the liver accumulation of the incorporated [(3) H]PGE(1) was significantly higher than that in control liposomes during the entire test period. The pharmacological activity was examined in mice with fulminant hepatitis induced by peritoneal injection of carbon tetrachloride. Intravenous injection of PGE(1) incorporated in DSPC/Chol/Gal-C4-Chol (60&ratio;35&ratio;5) liposomes significantly suppressed the GPT increase, whereas PGE(1) (dissolved in saline) and PGE(1) incorporated in DSPC/Chol (60&ratio;40) liposomes had little effect.

Alanine Transaminase↗
PubMed2000

[Detection methods for drug-resistant bacteria in routine examination--VRE].

When testing vancomycin susceptibility against enterococci, plates should be held a full 24 hours then examined using transmitted light. The presence of a haze or any growth within the zone of inhibition indicates resistance. Perform vancomycin MIC and tests for motility and pigment production to distinguish species with acquired resistance(vanA and vanB) from those with intrinsic, intermediate-level resistance to vancomycin(vanC) such as E. gallinarum, E. casseliflavus or E. flavescens.

Enterococcus↗
PubMed1999

MT neurons in the macaque exhibited two types of bimodal direction tuning as predicted by a model for visual motion detection.

We previously proposed a model for detecting local image velocity on the magnocellular visual pathway (Kawakami & Okamoto (1996) Vision Research, 36, 117-147). The model detects visual motion in two stages using the hierarchical network that includes component and pattern cells in area MT. To validate the model, we predicted two types of bimodal direction tuning for MT neurons. The first type is characteristic of component cells. The tuning is bimodal when stimulated with high-speed spots, but unimodal for low-speed spots or for bars. The interval between the two peaks widens as the spot's speed increases. The second type is characteristic of pattern cells. The tuning is bimodal when stimulated with low-speed bars, but unimodal for high-speed bars or for spots. The interval widens as the bar's speed decreases. To confirm this prediction, we studied the change of direction tuning curves for moving spots and bars in area MT of macaque monkeys. Out of 35 neurons measured at various speeds, six component cells and four pattern cells revealed the predicted bimodal tunings. This result provided neurophysiological support for the validity of the model. We believe ours is the first systematic study that records the two types of bimodality in MT neurons.

Animals↗
PubMed1999

Burn due to misuse of an acetylene gas burner: a case report.

A rare case of deep penetrating burn injury caused by misuse of a high-pressure acetylene burner is reported. A 35 year old man was admitted with second and third degree burns involving the right arm cubital area and a subcutaneous burn on his right arm caused by a high-pressure acetylene gas flame. Early surgical debridement and secondary skin grafting using a preserved subcutaneous vascular network skin graft (PSVNSG) proved effective in this patient. Skin contracture was prevented and function was recovered. The basis of PSVNSG is that the vascular system existing in the graft is used as a permanent vascular system without degeneration. This case shows that, in this kind of burn injury, subcutaneous tissue damage should be suspected and that it is important to perform surgical debridement early after admission.

Accidents, Home↗
PubMed1999

Use of the free medialis pedis flap in orofacial reconstruction: report of two cases.

The medialis pedis flap is a fasciocutaneous flap based on a branch of the medial plantar artery. The authors have used this flap in the reconstruction of skin defects of the hands and fingers because its skin is very similar in texture, color, and thickness. Because of its characteristics, this flap can also be applicable for orofacial reconstruction, when small or thin skin coverage is needed. Two cases are reported in which free medialis pedis flaps were used to reconstruct the eye socket in one patient and the alveolar ridge in the other. The authors concluded that the skin of the medialis pedis flap is not flexible enough and thus less suitable than the radial forearm flap for reconstruction of defects in which flexible skin is required, such as eye-socket reconstruction. However, reduced flexibility of the medialis pedis flap may provide an advantage in reconstruction of the gingiva and palate, where thin and rigid coverage is necessary.

Adult↗
PubMed1999

Radical surgery for Budd-Chiari syndrome. Direct excision and repair for obstruction of the vena cava (Budd-Chiari syndrome) under hepatic vascular exclusion using a centrifugal pump.

OBJECTIVE: To attempt to reduce the incidence of hepatic and cardiac failure after radical surgery for the Budd-Chiari syndrome. DESIGN: Retrospective case study. SETTING: University hospital, Japan SUBJECTS: Three patients with obstruction of the vena cava (Budd-Chiari syndrome) by a thick membrane, thrombus, and a long stenosis, respectively. INTERVENTION: Direct excision and repair by patch dilatation under hepatic vascular exclusion using a Biomedicus centrifugal pump. RESULTS: Hepatic vascular exclusion provides good visibility and enables accurate assessment of the obstruction, proper treatment, and relatively little blood loss. There were no complications, particularly liver failure or heart failure, and the inferior vena cava stayed patent in all cases. Liver function was improved in all three patients. CONCLUSION: This technique is safe and reliable for removal of obstruction of the inferior vena cava (Budd-Chiari syndrome).

Animals↗
PubMed1999

Adhesion preventive effect of hyaluronic acid after intraperitoneal surgery in mice.

Prevention of intraperitoneal adhesion after gynaecological surgery is essential for maintaining postoperative fertility. In this study, the adhesion prevention effect was examined of a hyaluronic acid (HA) solution obtained from the fermentation method and having a molecular weight of 1.9x10(6) with high viscosity. Laparotomy was conducted on female mice 7 weeks old, whose menstrual periods were synchronized by pregnant mare serum gonadotrophin (PMSG) to injure the uterine horn surface. Intraperitoneal adhesions were favourably formed in 91.7% of cases induced with iodine abrasion, compared with 50% induced by electrosurgery. Intraperitoneal administration of HA was evaluated for its effect on the prevention of adhesions made by iodine abrasion. Adhesion prevention effects of HA were observed at concentrations of 0.3, 0.5, 0.75 and 1.0%, among which the most pronounced effect was with the use of a 0.3% solution (92.3% of cases). Compared with the control group adhesion score of 2.0 +/- 0. 8, significant decreases in adhesion scores were observed at all concentrations. HA with a molecular weight of 1.9x10(6) was recognized to have a definitive prevention effect on postoperative adhesions in mice after laparotomy and is considered to be a prospective material for future clinical use.

Animals↗
PubMed1999

Detection of disseminated urothelial cancer cells in peripheral venous blood by a cytokeratin 20-specific nested reverse transcriptase-polymerase chain reaction.

More than half of all patients with invasive urothelial cancer subsequently develop metastatic disease even after radical resection of the primary cancer. In these patients, neoplastic cells may be disseminated prior to or during the operation. A nested reverse transcriptase-polymerase chain reaction (nested RT-PCR) assay which amplifies cytokeratin (CK) 20 transcripts was used to detect cancer cells in the peripheral blood of urothelial patients. This assay was able to detect 10 bladder cancer cell line cells in a sample of ten million peripheral-blood mononuclear (PBMN) cells. CK 20-specific signals were detected in 9 (22.5%) of 40 PBMN cell samples prepared from 40 urothelial cancer patients in relation to the tumor stage, including 0/13 patients with a superficial tumor, 4/21 (19%) with a regionally invasive tumor and 5/6 (83%) with a metastatic tumor (P = 0.0002 in chi 2 test). No signals were detected in any of 25 healthy donor PBMN cell samples. The present results indicate that the CK 20 RT-PCR assay is applicable for detection of urothelial cancer cells in the peripheral blood. The assay also confirms that hematogenic dissemination occurs in invasive urothelial cancers but rarely in superficial ones.

Biomarkers, Tumor↗
PubMed1999

[Effect of preventive measures against central venous catheter-related infection: retrospective study in our division for recent 10 years].

A study was made of 2202 central venous catheters (CVC), which were inserted for recent 10 years, to know the effect of preventive measures against CVC-related infection. We divided 10 years in 3 periods: 1987-1990 (the first period), 1991-1993 (the second period), and 1994-1996 (the third period). Preventive measures such as thorough antiseptic precaution, shortening of CVC dwelling time, and prohibition of injection from three-way stopcocks were taken after the second period. In the third period, semiclosed infusion system (I-system) was introduced to our division. A febrile catheterized patient (higher than 38 degrees C) was diagnosed as CVC-related infection when the fever dropped immediately (within 72 hours) after removal of CVC, or when the tip of the CVC was positive for culture. The rate of CVC-related infection in the second (9.9%) or the third (7.3%) period was significantly lower than that (14.0%) of the first period (p < 0.05 and p < 0.001, respectively). The mean dwelling time of CVC was 31.5 days for the first period, 27.0 days for the second period, and 24.8 days for the third period. The rate of long-term dwelling catheters (more than 29 days) in the second (34.5%) or the third (28.7%) period was significantly lower than that (40.5%) in the first period (p < 0.01 and p < 0.001, respectively). The index of CVC-related infection (incidence of infection per 1,000 days) was 4.8 for the first period, 3.7 for the second period, and 2.9 for the third period. The rate of infection of short-term dwelling CVC (less than 28 days) in the second (9.5%) or the third (6.3%) period was significantly lower than that (16.0%) of the first period (p < 0.01 and p < 0.001, respectively). As to cultures of CVC and/or blood sample, the isolation rate of fungi decreased significantly (p < 0.001), and that of gram-negative rods showed a tendency to increase after the second period. It was concluded that shortening of CVC dwelling time and application of semiclosed infusion system were effective to reduce the rate of CVC-related infection.

Aged↗
PubMed1999

[Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyou University Hospital--the first report].

We studied the cefotaxime (CTX)-resistant (MIC > or = 32 micrograms/ml) clinical isolates of E. coli and K. pneumoniae in Teikyo University Hospital from 1990 to 1996. The incidence of CTX-resistant isolates was 0.4% (6/1,282) in E. coli and 0.6% (7/1,044) in K. pneumoniae, in 1990. In 1995, the incidence of CTX-resistance increased to 1.7% (50/2,910) in E. coli (p = 0.0013) and 7.2% (144/1,996) in K. pneumoniae (p < 0.0001). These species have been detected in the stool (86 isolates), urine (59 isolates), sputum (15 isolates), pus (15 isolates), throat (10 isolates) and others (12 isolates) in 1995. MIC50 of ampicillin (ABPC), ABPC with clavlanic acid (CVA) 5 micrograms/ml, piperacillin (PIPC), PIPC with CVA 5 micrograms/ml, ceftazidime, CTX, ceftizoxime, cefpodoxime, cefepime, aztreonam, cefmetazole, latamoxef, and imipenem used against 33 isolates (11 isolates of E. coli, 22 isolates of K. pneumoniae), which were detected in 1996-1997, was > 512 micrograms/ml, 8 micrograms/ml, > 512 micrograms/ml, 8 micrograms/ml, 4 micrograms/ml, > 512 micrograms/ml, 16 micrograms/ml, > 512 micrograms/ml, 256 micrograms/ml, 32 micrograms/ml, 2 micrograms/ml, 0.25 microgram/ml and 0.25 microgram/ml, respectively. This susceptibility pattern were very similar to the Toho-1 type beta-lactamases producing strains.

Cefotaxime↗
PubMed1999

Phosphorylation and/or presence of serine 37 in the movement protein of tomato mosaic tobamovirus is essential for intracellular localization and stability in vivo.

The P30 movement protein (MP) of tomato mosaic tobamovirus (ToMV) is synthesized in the early stages of infection and is phosphorylated in vivo. Here, we determined that serine 37 and serine 238 in the ToMV MP are sites of phosphorylation. MP mutants in which serine was replaced by alanine at positions 37 and 238 (LQ37A238A) or at position 37 only (LQ37A) were not phosphorylated, and mutant viruses did not infect tobacco or tomato plants. By contrast, mutation of serine 238 to alanine did not affect the infectivity of the virus (LQ238A). To investigate the subcellular localization of mutant MPs, we constructed viruses that expressed each mutant MP fused with the green fluorescent protein (GFP) of Aequorea victoria. Wild-type and mutant LQ238A MP fusion proteins showed distinct temporally regulated patterns of MP-GFP localization in protoplasts and formation of fluorescent ring-shaped infection sites on Nicotiana benthamiana. However mutant virus LQ37A MP-GFP did not show a distinct pattern of localization or formation of fluorescent rings. Pulse-chase experiments revealed that MP produced by mutant virus LQ37A was less stable than wild-type and LQ238A MPs. MP which contained threonine at position 37 was phosphorylated, but the stability of the MP in vivo was very low. These studies suggest that the presence of serine at position 37 or phosphorylation of serine 37 is essential for intracellular localization and stability of the MP, which is necessary for the protein to function.

Alanine↗
PubMed1999

Regulation of lutenizing hormone secretion and subunit messenger ribonucleic acid expression by gonadal steroids in perifused pituitary cells from male monkeys and rats.

The mechanisms by which gonadal steroids regulate gonadotropin secretion remain incompletely understood. As previous studies suggest that the pituitary actions of testosterone (T) and estradiol (E) differ in male primates and rodents, we compared the effects of 10 nM T, 0.1 nM E, and 10 nM dihydrotestosterone (DHT) on the LH response to hourly pulses of GnRH as well as the GnRH receptor (GnRH-R) and LH subunit messenger RNA (mRNA) levels in dispersed pituitary cells from intact male monkeys and rats. T suppressed (P < 0.01) and E increased (P < 0.05) GnRH-stimulated LH secretion by rat pituitary cells. With monkey pituitary cells, on the other hand, there was no significant effect of either T or DHT on GnRH-stimulated LH secretion. In E-treated monkey cells, a period of initial enhancement (P < 0.05) was followed by significant suppression (P < 0.05) of LH secretion. GnRH-R mRNA was unchanged by T or E in either rat or monkey cells. T suppressed LHbeta (P < 0.01) and alpha-subunit (P < 0.01) mRNAs, whereas E increased alpha-subunit (P < 0.01), but did not alter LHbeta mRNA levels in rat cells. In monkey cells, however, neither T nor E affected LHbeta or alpha-subunit mRNA levels significantly. Our results identify different regulatory mechanisms by which testicular steroid hormones control LH secretion by the pituitary in male primates and rodents. We propose that the primary site of androgen negative feedback in the male primate is to restrain GnRH pulsatile secretion, whereas in the male rat T also decreases gonadotropin synthesis and secretion by directly affecting the pituitary. E suppresses GnRH-stimulated LH secretion in the primate pituitary, but amplifies the action of GnRH in the rat. Our data also reveal that the action of T to suppress LH secretion and subunit mRNA in male rats is not through decreased GnRH-R gene expression.

Animals↗
PubMed1999

[Long-term efficacy of the Gittes bladder neck suspension with use of ultrasonography for genuine stress urinary incontinence].

Thirty-eight patients with genuine stress incontinence underwent the Gittes procedures of the bladder neck suspension under ultrasonical monitoring. We performed the following two procedures. Original Gittes procedure: the puncture of the needle made twice through the different holes of the rectus fascia for each side and the bilateral helical suture was tied down separately above the rectus fascia. Modified Gittes procedure: the needle was passed through the rectus fascia once for each side and the both end of the helical suture was drawn up to suprapubic area, then the bilateral threads were tied over the rectus fascia. Original Gittes procedure was performed for twenty-nine patients and modified Gittes procedure for nine patients. Tightness of the suspension was decided by monitoring the posterior urethrovesical angle with use of the transrectal ultrasonography during the operation. A long term follow up survey was made up by means of a questionnaire by the phone or the mail. A total of thirty-six patients responded the questionnaire for a 94.7% response rate. The mean follow up was 33.1 months. 83.3% of the patients were cured and 5.6% were significantly improved. None of the patients claimed dysuria. There was no difference between the continent rates of the two procedures. We conclude that the Gittes bladder neck suspension with use of ultrasonography is effective for correction of female stress urinary incontinence.

Aged↗