PubMed Health⌕ Search

Biomedical subjects

Y Kashiwagi

Publications and source records attributed to Y Kashiwagi.

At least 19 recordsLinked to original sources
PubMed2004

Hepatic resection leads to predominance of the T helper-2 lymphocyte phenotype.

Recent studies have shown that the type 1/2 T helper (Th1/2) cell balance is shifted toward a Th2-type immune response not only by malignancy but also by surgical stress. This study evaluates in immune responses to surgical stress from liver surgery in comparison with other major abdominal surgeries. PATIENTS AND METHODS:: Eighty-five patients who underwent abdominal surgeries were divided into three groups: hepatic resection (n = 17), gastric resection (n = 38), and colorectal resection (n = 30). Blood sampling was performed before surgery, and on postoperative days (POD) 2 and 14. Cell surface markers were used to characterize Th1/2 balance by flow cytometry and a ratio of the percent IFN-gamma-producing (Th1) cells to IL-4-producing (Th2) cells were expressed as the Th1/2 balance. RESULTS:: The postoperative ratio of Th1 to Th2 was decreased significantly in all subjects to 4.5 +/- 3.0 on POD 2 from 6.7 +/- 4.2. The ratio of Th1 to Th2 in patients who underwent hepatic resection markedly decreased to 2.8 +/- 1.6 on POD 2, significantly different from those in patients undergoing gastric resection or colorectal resection. However, on POD 14 there were no longer any significant differences among the three surgical groups. CONCLUSIONS:: This study shows that hepatic resection induces a more marked shift of the Th1/2 balance toward Th2 than other major abdominal surgeries.

Journal Article↗
PubMed2003

Telomeric repeat sequence of Aspergillus oryzae consists of dodeca-nucleotides.

Four telomeres in the chromosomes of Aspergillus oryzae NFRI1599 were cloned and sequenced. The telomeric repeat sequence of A. oryzae consisted of dodeca-nucleotides: TTAGGGTCAACA. The length of the telomeric repeat tract was 114-136 bp, which corresponds to 9-11 repeats of the dodeca-nucleotide sequence. Compared to a chromosome internal control (18S rDNA), the telomeric sequences were found to be sensitive to BAL31 exonuclease digestion, thus proving that the identified telomeric repeat sequences were located at the most terminal tract of the chromosomes. The length of the telomeric repeat tract of A. oryzae is similar to that of Aspergillus nidulans, whose repeat unit is TTAGGG, indicating that the regulatory mechanism of telomere length might be conserved among Aspergillus species.

Aspergillus oryzae↗
PubMed2003

NOx (nitrite/nitrate) in cerebral spinal fluids obtained from patients with influenza-associated encephalopathy.

It has become evident that the number of patients with a new type of influenza-associated encephalopathy is increasing in Japan. Nitric oxide (NO), a simple free radical gas, elicits a wide range of physiological and pathophysiological effects. We measured the nitrite/nitrate (NO x ) levels in cerebral spinal fluid obtained from patients with influenza-associated encephalopathy in order to evaluate the correlation between the NO production and the process of influenza-associated encephalopathy. Fifteen children were enrolled, aged from 1 to 9 years. As control we used 14 cerebral spinal fluids obtained from patients with urinary tract infection, respiratory infection or mumps meningitis without any sequela. NO 3 in influenza-associated encephalopathy was significantly higher than that of control group. On the other hand NO 2 was not significantly higher than that of control group. In particular, 4 out of 5 fatal cases revealed high NO 2 or NO 3. One case having normal levels in NO 2 and NO 3 showed that NH 3 was high. These results revealed that NO plays a role in influenza-associated encephalopathy through indirect effects of NO.

Brain↗
PubMed2001

Ellagitannins and hexahydroxydiphenoyl esters as inhibitors of vertebrate squalene epoxidase.

Ellagitannins isolated from various plant sources as well as newly synthesized n-alkyl (C(1)-C(18)) esters of hexahydroxydiphenyl (HHDP) dicarboxylic acid were evaluated as enzyme inhibitors of recombinant rat squalene epoxidase, a rate-limiting enzyme of cholesterol biosynthesis. Among the ellagitannins tested, pedunculagin (IC(50) = 2.0 microM) and eugeniin (IC(50) = 1.6 microM), both containing (S)-HHDP ester group(s), showed remarkable inhibition, which was more potent than those of previously reported substrate analogue inhibitors. Furthermore, ellagic acid (IC(50) = 2.0 microM), a bislactone formed by hydrolytic release of a HHDP group from ellagitannins, was also a good inhibitor of the enzyme. On the other hand, the synthetic HHDP esters with C(6) (IC(50) = 0.93 microM) and C(8) alkyl side chains (IC(50) = 0.83 microM) showed potent enzyme inhibition at the submicromolar concentration range, while esters with shorter chain lengths (C(1)-C(4)) and a C(18) ester exhibited moderate inhibition (IC(50) = 8-47 microM).

Animals↗
PubMed2001

Visual stimulation-induced phosphorylation of neurofilament-L in the visual cortex of dark-reared rats.

In dark-reared animals, visual exposure is expected to induce drastic changes in both the physiology and anatomy of the cortical neurons, including the rearrangement of their cytoskeletal structures. Phosphorylation of neurofilament-L (NF-L) is probably associated with relatively short-term structural plasticity in vivo, because the assembly and disassembly of the filaments are regulated by phosphorylation of the head domain of NF-L. Thus, by using a series of site- and phosphorylation state-specific antibodies against NF-L, we examined how visual activation induces the phosphorylation of NF-L in the rat brain. We found no specific immunoreactivity for phosphorylated NF-L in the brain of naive rats, whereas one-hour ambient light exposure after dark rearing for ten weeks from birth induced marked phosphorylation of NF-L selectively. Also, the NF-L phosphorylation was found to be localized in the primary and secondary visual cortical areas. These findings suggest that the selective phosphorylation of NF-L plays an important role in the structural plasticity related to the visual experience.

Amino Acid Sequence↗
PubMed2001

Cytomegalovirus DNA among children attending two day-care centers in Tokyo.

BACKGROUND: In the USA, a high prevalence rate of cytomegalovirus (CMV) excretion among children in day-care centres was reported. However, there is no research about the prevalence rate of CMV among children in day-care centres in Japan. METHODS: The CMV excretion was studied in 54 children's saliva samples, collected from two different day-care centres in Tokyo. As a control, the prevalence of CMV was studied among 61 healthy children who did not attend any day-care centers. The CMV DNA in saliva were examined by polymerase chain reaction (PCR) analysis with one pair of primers for the immediate early region. The sequence of CMV genomes were examined in CMV PCR positive samples. RESULTS: Of the 54 saliva samples, 20.6% (6/29) and 24% (6/25) were CMV PCR positive in children at A and B day-care centres, respectively. The overall positivity of CMV PCR in saliva was 22.2% (12/54). Of the 61 saliva samples as the control study, 6.5% (4/61) were CMV PCR positive. There was a difference in the positivity in each age group of day-care centres and normal control. Each sample of the same day-care center gave conclusive and identical sequence results. CONCLUSION: We suspected that in each day-care center that there was one prevailing viral strain. We suppose that CMV infections were acquired inside the day-care centres. This is a first report which described viral transmission in day-care centres in Japan.

Child Day Care Centers↗
PubMed2001

[Epidemiological survey for hemolytic streptococci isolated from children in Tokyo].

During the 20-year period between 1979-1998, a total of 4,176 strains of hemolytic streptococci have been isolated from 20,118 healthy primary school children and little children in Tokyo Metropolitan (Tokubetsuku, Tama and Tosho). Culture of throat swabs every November and the following February during the 20-year period were made and serological grouping and typing for isolates were done by T agglutination method. The results were as follows. 1) Serological group of hemolytic streptococci isolated from children were 3,188 strains (76.3%) for isolates of group A out of total strains of 4,176, 569 strains (13.6%) for isolates group B, 63 strains (1.5%) for isolates of group C and 356 strains (8.5%) for isolates of group G. 2) The most dominant was T12 during 1979-1998, and other relatively frequent serotypes were T28, T1, T4, T6 in that order. These ranks of and the main epidemic serotypes showed a similar trend in the 3 areas. 3) The isolation rates of group A streptococci were 15.9% in Tokubetsuku, 17.1% in Tama and 14.9% in Tosho. The average of 3 areas were 15.8%. 4) The epidemic cases seemed to be caused by group A streptococci were 20 cases, their isolated serotype were 7 cases by T28, 5 cases by T12, 4 cases by T6, 2 cases by T4, each 1 case by T1 and T25. 5) A total of 2,927 strains of group A streptococci were examined for drug sensitivity. All strains were sensitive to beta-lactam group of antibiotics (benzylpenicillin and cephaloridine). Resistant (MIC > or = 25 micrograms/ml) to TC, CP and EM etc. were 740 strains (25.3%) in this study. The incidence of resistant strains were to TC 493 strains (66.6%) out of 740 strains, 81 strains (10.9%) for TC.CP, 72 strains (9.7%) for EM and 66 strains (8.9%) for TC.CP.EM.OL.LCM. TC resistant strains have not varied much through the whole period, but CP and EM resistant strains were very variable by year. Many resistant strains to TC were T4, to EM and multiple drug resistant were T12. 6) The rates of isolates of the same type of group A streptococci in school child individual during for the tests taken twice a year were 12.3%, indicating group A streptococci, according to the duration of the carrier state, seems to be a short period.

Child↗
PubMed2001

Selective electrocatalytic oxidation of N-alkyl-N-methylanilines to N-alkylformanilides using nitroxyl radical.

Electrocatalytic oxidation of N-alkyl-N-methylanilines was studied using 4-benzoyloxy-2,2,6,6-tetramethyl-piperidinyl-N-oxyl as a nitroxyl radical. The reaction with N-alkyl-N-methylanilines led to direct formation of N-alkylformanilides in the presence of H2O in reaction media in adequate conversion (>75.8%), high current efficiency (>89.2%) and high selectivity (>93.8%).

Anilides↗
PubMed2001

[Optimal setting of focus points for myocardial contrast echocardiography with intravenous Optison (FS-69): an experimental study].

OBJECTIVES: Myocardial contrast echocardiography is useful to assess myocardil perfusion, but myocardial opacification is affected by the setup of the ultrasonic equipment. The optimal setting of focus points for adequate opacification of the myocardium was examined in myocardial contrast echocardiography. METHODS: Myocardial contrast echocardiography was performed in six dogs using triggered second harmonic technology following intravenous administration of Optison(FS-69). The short-axis view was recorded and baseline subtracted video intensity(peak intensity: PI) was calculated at three regions of the left ventricular wall, the anterior, septum, and posterior walls, to evaluate myocardial opacification. The focus point was set at near(2 cm), middle(4 cm) and far(6 cm)points. The myocardial opacification was evaluated at each focus setting. The effect of the acoustic power was also examined by changing the mechanical index to 1.6, 1.2 or 0.8. RESULTS: Myocardial opacification was recognized at all focus points, and segments near the focus points had high PI. However, the PI of the posterior wall was lowest at near focus, whereas the PI of the anterior wall was lowest at far focus. The difference of PI between the anterior and posterior walls was significant (p < 0.05, p < 0.01, respectively) at either focus point. Adequate myocardial opacification of all segments was observed when the focus was set at the middle point. The PI of the whole left ventricle increased relative to mechanical index. CONCLUSIONS: Setting up of focus points at the middle of the left ventricle provides more homogeneous myocardial opacification of the whole left ventricle in myocardial contrast echocardiography, and high acoustic power possibly improves myocardial opacification. Inadequate setting of focus points leads to inadequate estimation of myocardial perfusion by myocardial contrast echocardiography.

Albumins↗
PubMed2001

[Usefulness of intravenous myocardial contrast echocardiography in rats].

OBJECTIVES: Few intravenous myocardial contrast echocardiography trials have evaluated myocardial perfusion in small animals. The feasibility of using intravenous myocardial contrast echocardiography to assess the ischemic area in rats was investigated. METHODS: Fourteen open chest Wister male rats were examined. Intravenous myocardial contrast echocardiography was performed by fundamental and intermittent mode using a high frequency (5-12 MHz) transducer (SONOS 5500) with injection of NC100100 (20% dilution) into the femoral vein. The mechanical index was set to 1.6. Baseline-subtracted video intensity (256 level) was measured in the anterior, posterior, septal and lateral walls of the left ventricle. The left anterior descending artery was ligated in 16 rats. The area at risk was evaluated by myocardial contrast echocardiography and compared to the area of defect by Evans Blue staining. RESULTS: All wall segments were clearly opacified (anterior 63.8 +/- 24.7, posterior 27.0 +/- 11.0, septal 44.5 +/- 11.6, lateral 52.3 +/- 19.1), although the baseline-subtracted video intensity of the posterior wall was low. The area at risk was clearly observed, and there was a good correlation with the nonperfused area by Evans Blue staining (y = 1.13x-3.54, r = 0.98). CONCLUSIONS: Intravenous myocardial contrast echocardiography can detect the perfusion defect even in rats using a high frequency transducer and suitable setup of equipment.

Animals↗
PubMed2001

[Effect of oxygen inhalation on myocardial opacification using levovist: an animal experimental study].

OBJECTIVES: Levovist can opacify the myocardium via venous injection, and is widely used in the clinical field. However, left ventricular opacification deteriorates during oxygen inhalation using Albunex, one of the first generation of contrast agents. This study examines the effect of blood oxygen pressure on the myocardial opacification by Levovist. METHODS: Myocardial contrast echocardiography (Toshiba Power Vision 6000) was performed using second harmonic imaging, intermittent exposure of ultrasound (every 4 cardiac beats) and acoustic power of 1.4 mechanical index. The video intensity of the ventricular septum after venous injection of Levovist (0.5 ml of 300 mg/ml) was measured under various respiratory conditions by manipulating the respirator and oxygen inhalation. Arterial blood gas was measured and correlated with the myocardial video intensity. RESULTS: The video intensity of myocardial opacification was lower with higher oxygen pressure in the arterial blood. Visual recognition of myocardial opacification was only 14% under high oxygen pressure over 200 mmHg. Microbubbles of Levovist form from normal air, and are easily affected by the gas concentration of the surrounding blood. CONCLUSIONS: Myocardial opacification using Levovist is deteriorated under high oxygen pressure at examination.

Administration, Inhalation↗
PubMed2000

Inhibition of vertebrate squalene epoxidase by isoprenyl gallates and phenylalkyl gallates.

Galloy esters with 'substrate-like' isoprenoid or phenylalkyl side chains were newly synthesized and tested for the enzyme inhibition activities toward recombinant rat squalene epoxidase. Isoprenyl gallates (4-6) showed good inhibition (IC50 = 1.5 5.1 microM), as potent as previously reported substrate analogues, while phenylalkyl gallates (7-10) were moderate inhibitors of the enzyme (IC50 = 12-61 microM).

Animals↗
PubMed2000

Phosphorylation of neurofilament-L during LTD.

We recently reported that CaMKII-dependent phosphorylation of the neurofilament-L (NF-L) head domain was induced in the apical dendrites during long-term potentiation. Long-term depression (LTD) is another cellular model for neuronal plasticity. In the present study, we examined the phosphorylation of NF-L during hippocampal LTD using a series of phospho-specific antibodies against the NF-L head domain. During LTD, these antibodies visualized NF-L phosphorylation at Ser57 in the apical dendrites of the hippocampal pyramidal neurons. The assembly and disassembly of NF-L filaments are regulated by phosphorylation of its head domain. Thus, our results indicated that NF-L phosphorylation might be associated with alterations of the neuronal structure during LTD.

Animals↗
PubMed2000

Loss of diurnal variation in ornithine decarboxylase and apoptosis in small intestine of Mongolian gerbils.

The aim of this study was to examine the diurnal variations in ornithine decarboxylase (ODC) activity and apoptosis in the small intestinal mucosa of Mongolian gerbils. First, the feeding, drinking, and ambulatory patterns of the gerbils were recorded. The results indicated that Mongolian gerbils lost diurnal cyclicity in feeding, drinking, and ambulatory patterns. Second, ODC activity and apoptosis in the intestinal mucosa of gerbils were characterized by measurements at four time points (11:00, 17:00, 23:00, and 05:00 h; light period, 08:00-20:00 h). Apoptosis was evaluated in terms of percent fragmented DNA (fragmented DNA/total DNA). Neither ODC activity nor apoptosis showed diurnal variation in the jejunal mucosa of the Mongolian gerbils. In 48-h fasted gerbils, ODC activity in the intestinal mucosa decreased, but this activity increased significantly 2 h after refeeding; percent fragmented DNA increased in the intestinal mucosa, and returned to the control level 2 h after refeeding. These results indicate that postprandial local nutrients are an important factor in regulating diurnal variation in ODC activity and apoptosis in the small intestine of gerbils.

Animals↗
PubMed2000

An electrospray-ionization mass spectrometry analysis of the pH-dependent dissociation and denaturation processes of a heterodimeric protein.

Electrospray ionization mass spectrometry (ESI-MS) was applied to the analysis of the dissociation and denaturation processes of a heterodimeric yeast killer toxin SMKT. The two distinct subunits of SMKT noncovalently associate under acidic conditions, but become dissociated and denatured under neutral and basic conditions. In order to understand the unique pH-dependent denaturation mechanism of this protein, a pH titration was performed by utilizing ESI-MS. The molecular ions of the heterodimer which possesses the highly ordered structure, were mainly observed below pH 4.6. However, the two subunits immediately dissociated at this pH. The spectra measured with various settings of the mass spectrometer indirectly demonstrated that the pH-dependent dissociation occurs in the liquid phase. The current result as well as the three-dimensional structure of SMKT suggest that the deprotonation of a specific carboxyl group triggers a cooperative dissociation process of this protein. In conclusion, the pH titration of a protein by ESI-MS is particularly effective, when the unfolding process or the biological function of the protein is related to the interaction with other molecules.

Fungal Proteins↗
PubMed2000

Detection and sequencing of measles virus from peripheral mononuclear cells from patients with inflammatory bowel disease and autism.

It has been reported that measles virus may be present in the intestine of patients with Crohn's disease. Additionally, a new syndrome has been reported in children with autism who exhibited developmental regression and gastrointestinal symptoms (autistic enterocolitis), in some cases soon after MMR vaccine. It is not known whether the virus, if confirmed to be present in these patients, derives from either wild strains or vaccine strains. In order to characterize the strains that may be present, we have carried out the detection of measles genomic RNA in peripheral mononuclear cells (PBMC) in eight patients with Crohn's disease, three patients with ulcerative colitis, and nine children with autistic enterocolitis. As controls, we examined healthy children and patients with SSPE, SLE, HIV-1 (a total of eight cases). RNA was purified from PBMC by Ficoll-paque, followed by reverse transcription using AMV; cDNAs were subjected to nested PCR for detection of specific regions of the hemagglutinin (H) and fusion (F) gene regions. Positive samples were sequenced directly, in nucleotides 8393-8676 (H region) or 5325-5465 (from noncoding F to coding F region). One of eight patients with Crohn disease, one of three patients with ulcerative colitis, and three of nine children with autism, were positive. Controls were all negative. The sequences obtained from the patients with Crohn's disease shared the characteristics with wild-strain virus. The sequences obtained from the patients with ulcerative colitis and children with autism were consistent with being vaccine strains. The results were concordant with the exposure history of the patients. Persistence of measles virus was confirmed in PBMC in some patients with chronic intestinal inflammation.

Adult↗
PubMed2000

Localized phosphorylation of vimentin by rho-kinase in neuroblastoma N2a cells.

BACKGROUND: Vimentin, which is one of the intermediate filaments, is the major cytoskeletal component in developing neurones or neuroblastoma cells. Rho-associated kinase (Rho-kinase), is rich in neurones and is found downstream of Rho. It is involved in the agonist-induced neurite retraction of neuronal cells, and phosphorylates vimentin at Ser-38 and Ser-71 resulting in in vitro disassembly of the filaments. RESULTS: We have investigated the distribution of vimentin phosphorylated by Rho-kinase in N2a neuroblastoma cells using site-specific phosphorylation-dependent antibodies. TM71 immunoreactivity, which specifically indicates Ser-71 phosphorylation on vimentin, was found in some neurites of dibutyryl cAMP-differentiated N2a cells. Transfection of the constitutively active form of Rho-kinase, CAT, significantly elevated TM71 immunoreactivity, and induced neurite retraction or cell rounding. Conversely, transfection of the dominant negative form of Rho-kinase, RB/PH(TT), or treatment of 10 microM Y-27632, a Rho-kinase specific inhibitor, abolished TM71 immuno-reactivity, and induced irregular neurite outgrowth. In contrast, 20 nM okadaic acid (OA) induced neurite retraction and specifically elevated TM71 immunoreactivity. In the OA-induced neurite retraction, tubulin disappeared in retracting neurites, where vimentin and actin remained co-localized. Furthermore, the OA-induced elevation of TM71 immunoreactivity and neurite retraction were completely blocked by pretreatment with 10 microM Y-27632, or by the ectopic expression of RB/PH(TT). CONCLUSIONS: This study suggests that the localized phosphorylation of vimentin by Rho-kinase in neurites was closely related with the cellular morphology of N2a cells, and that the Rho-kinase activity towards vimentin was balanced with OA-sensitive phosphatases.

Amides↗