Biomedical subjects

M Yoshioka

Publications and source records attributed to M Yoshioka.

At least 19 recordsLinked to original sources

PubMed2006

Specific detection of prion antigenic determinants retained in bovine meat and bone meal by flow microbead immunoassay.

AIMS: The purpose of this study was to develop an effective method for detecting prion (PrP) antigenic determinants remaining in bovine meat and bone meal (MBM) using pressurized fluid extraction (PSE) equipment and flow microbead immunoassay (FMI). METHODS AND RESULTS: Using the FMI, bovine recombinant PrP could be determined quantitatively in the 7 pmol-7 nmol range using anti-PrP peptide polyclonal antibody-coupled microbeads and anti-PrP monoclonal antibody (SAF61) as a detection antibody. PSE extraction at 120 degrees C for 5 min under high pressure was most effective for eluting PrP determinants from bovine MBMs. The FMI was capable of detecting PrP determinants in bovine MBM extracts with high specificity and indicated that the MBMs contained high levels of PrP determinants. This assay was also applied to the detection of PrP(Sc) determinants in bovine MBM spiked with a scrapie-infected brain at a weight ratio of 50 : 1. CONCLUSIONS: These data indicate that this assay was effective for the specific detection of PrP determinants contained in bovine MBM extracts. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first report detailing the detection of PrP determinants in bovine MBM. The assay could be applied to securing the safety of bovine MBM.

Animal Feed↗

PubMed2006

Salivary immunoglobulin A directed to oral microbial GroEL in patients with periodontitis and their potential protective role.

The aim of this study was to identify salivary immunoglobulin A (IgA) directed to oral microbial GroEL in patients with periodontitis and to demonstrate their potential protective role through a reduction of inflammatory cytokine production induced by microbial GroEL. Using five different proteins belonging to the heat-shock protein 60 family, Western immunoblot analysis of salivary IgA from 63 subjects revealed immunoreactivities with Campylobacter rectus GroEL and Porphyromonas gingivalis GroEL in subjects with periodontitis (P < 0.05) compared to control subjects. Using the BIACORE 1000 to measure the salivary IgA titers directed towards C. rectus GroEL, high resonance unit (RU) values were observed in the saliva samples from patients with periodontitis (P < 0.01). Furthermore, the number of teeth with deep pocket depth (>or=5 mm) showed a high correlation coefficient with the RU value (r = 0.50, P < 0.01). C. rectus GroEL possessed the ability to stimulate the production of interleukin-6 by gingival fibroblasts. Interestingly, salivary IgA antibody directed to C. rectus GroEL caused a partial inhibition of interleukin-6 production. This study showed a relationship between high levels of salivary IgA directed to GroEL and periodontal disease severity. Although additional investigations are required, salivary IgA to GroEL may have a protective role by reducing the inflammatory response induced by GroEL derived from periodontopathogenic bacteria.

Adult↗

PubMed2006

Cardiovascular dysautonomia in Parkinson's disease and multiple system atrophy.

OBJECTIVES: To determine whether Parkinson's disease (PD) can be distinguished from multiple system atrophy (MSA) on the basis of the assessment of iodine-123 meta-iodobenzylguanidine (123I-MIBG) radioactivity in heart and cardiovascular autonomic function. PATIENTS AND METHODS: Seventeen patients with MSA, 39 with PD, and 25 healthy volunteers underwent 123I-MIBG scintigraphy and hemodynamic autonomic function tests using Valsalva maneuver (VM). Baroreceptor reflex sensitivity (BRS) was measured using the slope of the relation between RR interval and blood pressure during the fourth phase. RESULTS: 123I-MIBG radioactivity in heart of patients with PD was lower than that of control subjects and patients with MSA, but there was some overlap between PD and MSA. BRS in patients with PD who had a 123I-MIBG radioactivity similar to that in MSA was larger than that in patients with MSA, with no overlap in any patient. CONCLUSION: Assessment of BRS may be useful for differentiating between MSA and PD that had a 123I-MIBG radioactivity similar to MSA.

3-Iodobenzylguanidine↗

PubMed2006

Effects of dihydrotestosterone on skeletal muscle transcriptome in mice measured by serial analysis of gene expression.

In order to characterize the action of androgen in skeletal muscle, we have investigated the effects of castration (GDX) and dihydrotestosterone (DHT) on global gene expression in mice. The serial analysis of gene expression method was performed in the muscle of male mice in six experimental groups: intact, GDX and GDX+DHT injection 1, 3, 6 or 24 h before they were killed. A total of 780 822 sequenced tags quantified the expression level of 80 142 tag species. Thirteen and seventy-nine transcripts were differentially expressed in GDX and DHT respectively (P < 0.05), including eight partially characterized and 21 potential novel transcripts. The induced transcripts within 3 h after DHT injection were involved in the following functions: transcription, protein synthesis, modification and degradation, muscle contraction and relaxation, cell signaling, polyamine biosynthesis, cell cycle progression and arrest, angiogenesis, energy metabolism and immunity. However, the inductions of transcripts related to cell cycle arrest and angiogenesis were no longer significant 24 h after DHT injection. The current study might suggest that DHT promotes protein synthesis, cell signaling, cell proliferation and ATP production, as well as muscle contraction and relaxation at the transcriptional level in skeletal muscle in vivo.

Animals↗

PubMed2005

Reproducibility, bioinformatic analysis and power of the SAGE method to evaluate changes in transcriptome.

The serial analysis of gene expression (SAGE) method is used to study global gene expression in cells or tissues in various experimental conditions. However, its reproducibility has not yet been definitively assessed. In this study, we have evaluated the reproducibility of the SAGE method and identified the factors that affect it. The determination coefficient (R2 ) for the reproducibility of SAGE is 0.96. However, there are some factors that can affect the reproducibility of SAGE, such as the replication of concatemers and ditags, the number of sequenced tags and double PCR amplification of ditags. Thus, corrections for these factors must be made to ensure the reproducibility and accuracy of SAGE results. A bioinformatic analysis of SAGE data is also presented in order to eliminate these artifacts. Finally, the current study shows that increasing the number of sequenced tags improves the power of the method to detect transcripts and their regulation by experimental conditions.

Animals↗

PubMed2005

Long-period accelerometer monitoring shows the role of physical activity in overweight and obesity.

CONTEXT: Physical activity (PA) plays an important role in obesity. A new accelerometer has been developed to assess total energy expenditure as well as PA. OBJECTIVE: To investigate the association of PA with overweight and obesity in Japanese men and women, a large cross-sectional study was performed using a single-axis accelerometer. DESIGN, SETTING AND PARTICIPANTS: Population-based cross-sectional study of Japanese 18-84 y of age. Height, body weight and PA were measured in 400 male and 388 female Japanese volunteers from 1999 to 2000. The outcome measurements were overweight and obesity, which are defined as a body mass index >/=25 kg/m(2). PA was measured for 1 to 4 weeks and was then categorized into three activity levels, which were defined as light, moderate and vigorous PA. RESULTS: Prevalence of overweight and obesity was 22.3%. Number of steps and time spent in moderate and vigorous PA per day were lower in overweight and obese individuals. No difference was found in time spent in light PA. Individuals who are in the 4th and 5th quintile of moderate and vigorous PA showed a significantly lower body mass index. When odd ratios (ORs) of overweight and obesity estimated by logistic regression were used as effect measures, overweight and obesity were negatively associated with vigorous PA (ORs=0.91). CONCLUSION: These results indicate that overweight and obese individuals have a lower step rate and are spending less time for moderate to vigorous PA. Participation in vigorous PA is an important predictor of overweight and obesity.

Adolescent↗

PubMed2005

Binding of Actinobacillus actinomycetemcomitans lipopolysaccharides to Peptostreptococcus micros stimulates tumor necrosis factor alpha production by macrophage-like cells.

Peptostreptococcus micros is a gram-positive bacterium that has been associated with periodontitis and endodontic infections. In this study, we hypothesized that P. micros binds the immunomodulating component lipopolysaccharide derived from gram-negative bacteria to increase its capacity to stimulate cytokine production by host cells. The ability of P. micros to bind Actinobacillus actinomycetemcomitans lipopolysaccharide was demonstrated by an enzyme-linked immunosorbent assay and by immunoelectron microscopy. Pretreatment of P. micros cells with A. actinomycetemcomitans lipopolysaccharide was associated with a 49-fold increase in tumor necrosis factor alpha production by human monocytic cells U937 differentiated into adherent macrophages, compared to the stimulation with untreated P. micros. This effect was suppressed by incorporating polymyxin B, a lipid A-binding substance, during treatment of macrophage-like cells with lipopolysaccharide-coated P. micros cells. This is the first study reporting a binding interaction between lipopolysaccharide and a gram-positive bacterium. This interaction represents a new mechanism that could promote the inflammatory response during periodontitis.

Aggregatibacter actinomycetemcomitans↗

PubMed2005

Effect of female sex hormones on Campylobacter rectus and human gingival fibroblasts.

Recent studies have suggested a relationship between maternal Campylobacter rectus infections and preterm low birth weight. The purpose of this study was to investigate the effect of female sex hormones, estradiol and progesterone, on C. rectus and human gingival fibroblasts (HGF). The growth of C. rectus was significantly enhanced by incorporating either estradiol or progesterone in the culture medium. The production of vascular endothelial growth factor (VEGF), interleukin (IL)-6 and IL-8 by HGF increased following stimulation with estradiol or progesterone, at concentrations comparable to those present in the plasma of pregnant women. In addition, a significantly higher secretion of VEGF by HGF treated with the combination of C. rectus and estradiol was observed in comparison with a treatment with C. rectus alone. Stimulation of HGF with VEGF resulted in production of IL-6 and IL-8 in a dose-dependent manner. The capacity of female sex hormones to enhance both C. rectus growth and VEGF, IL-6, and IL-8 production by HGF has the potential to contribute to periodontal disease progression during pregnancy.

Campylobacter rectus↗

PubMed2005

Experimental acute alcohol pancreatitis-related liver damage and endotoxemia: synbiotics but not metronidazole have a protective effect.

OBJECTIVE: The aim of this study was to test the effect of gut manipulation by either novel synbiotics or by metronidazole on either endotoxemia or the severity of liver damage in the course of acute pancreatitis from alcohol ingestion. METHODS: Sprague-Dawley rats were fed for 1 week through an intragastric tube a liquid diet with either: (i) 1 mL t.i.d. of a mixture of synbiotics (Lactobacillus acidophilus, Lactobacillus helveticus and Bifidobacterium in an enriched medium); (ii) 20 mg/kg t.i.d. metronidazole; or (iii) standard diet. Then, acute pancreatitis was induced by caerulein and when the disease was full-blown, rats were fed an alcohol-rich diet. Synbiotic and metronidazole treatment was given for a further 2 weeks. Transaminase and endotoxemia levels were measured before treatment, after 6 h, after 24 h and 2 weeks later, at the time the rats were killed. Liver samples were obtained for histological analysis. RESULTS: Synbiotics but not metronidazole improved the acute pancreatitis-induced increase in endotoxemia and transaminase levels. The addition of alcohol worsened these variables to a limited extent in the synbiotic-treated group, while metronidazole had a negative effect on liver damage. CONCLUSIONS: Gut flora pretreatment with synbiotics was able to effectively protect against endotoxin/bacterial translocation, as well as liver damage in the course of acute pancreatitis and concomitant heavy alcohol consumption. The beneficial effect of synbiotics on liver histology seems to be correlated with endotoxemia. Metronidazole did not produce such a beneficial effect; in fact, it further worsened liver damage when alcohol was added to the background of ongoing acute pancreatic inflammation.

Acute Disease↗

PubMed2005

Estrous cycle characterisation and artificial insemination using frozen-thawed spermatozoa in the bottlenose dolphin (Tursiops truncatus).

The reproductive endocrinology of the bottlenose dolphin, Tursiops truncatus, was characterized to facilitate the development of artificial insemination using cryopreserved spermatozoa. Specific objectives were: (i) to determine the excretory dynamics of urinary luteinizing hormone (LH) and ovarian steroid metabolites during the estrous cycle; (ii) to evaluate the effect of an exogenously administered synthetic progesterone analog (altrenogest) on reproductive hormone excretion; (iii) to correlate follicular growth and ovulation (as determined by transabdominal ultrasound) to urinary LH and ovarian steroid metabolites; (iv) examine the in vivo fertilisation capacity of cryopreserved semen, and (v) to develop an intrauterine insemination technique. Based on urinary endocrine monitoring of natural estrous cycles (2 consecutive cycles) and nine post altrenogest cycles in ten females, estrous cycles were found to be 36 days long and comprised of an 8 day and 19 day follicular and luteal phase, respectively. Peak estrogen conjugates (EC; 5.4+/-3.8 ng/mg creatinine (Cr)) occurred 8 h prior to the LH surge (70.9+/-115.7 ng/mg Cr). The time of ovulation, as determined by ultrasonography, occurred 32.1+/-8.9 h and 24.3+/-7.0 h after the onset of the LH surge and LH peak, respectively. Mean preovulatory follicular diameter and circumference were 2.1+/-0.5 cm and 6.5+/-1.5 cm, respectively. Of the 27 estrous synchronisation attempts, 13 resulted in an ovulatory cycle, with ovulation occurring 21 days post-altrenogest treatment. Intrauterine (4 of 5) and intracornual (1 of 3) inseminations conducted across eight estrous cycles resulted in five pregnancies (63%), one pregnancy resulted from the use of liquid stored semen, whereas four were achieved using cryopreserved semen. These data provide new information on female bottlenose dolphin reproductive physiology, and demonstrate that the combination of endocrine monitoring and serial ultrasonography contributed to successful AI using liquid-stored and cryopreserved semen.

Animals↗

PubMed2005

[Hemothorax following intraabdominal bleeding due to pedicle torsion of ovarian tumor via a small pore in the diaphragm: report of a case].

On February 25, 2004, 59-year-old woman visited a local clinic due to lower abdominal pain. On February 28, she was admitted to the clinic due to severe abdominal pain. Computed tomography (CT) showed a mass in the lower abdomen and plural effusion and athelectasis of the right lung. She had severe anemia (Hb 6.9 g/dl). On March 1, she was transferred to our hospital. Pleural fluid was revealed to be sanguineous by thoracentasis. She underwent thoracotomy on the day of admission. There was no source of bleeding in the pleural space. A small pore, 3 mm in diameter, was found in the tendinous portion of the diaphragm. An influx of bloody fluid from the abdomen via the pore caused hemothorax. Laparotomy was performed, followed by closure of the pore using direct suture. The origin of the abdominal bleeding was pedicle torsion of the right ovarian tumor. Seven months after surgery she was uneventful with no pleural effusion.

Abdominal Cavity↗

PubMed2005

[Coronary artery bypass graftingin a patient with aortitis syndrome; report of a case].

We present a case of surgical treatment for a coronary lesion due to aortitis syndrome. A 41-year-old woman, suffering from aortitis syndrome and under prednisolone (PSL) therapy, underwent coronary artery bypass grafting (CABG). Surgical treatment was performed according to the aortic no-touch technique, but the patient showed a poor cardiac performance 5 days after the operation. This accident was resolved by increasing the PSL dose. Aortitis syndrome treated with PSL needs careful perioperative management besides an operative procedure.

Adult↗

PubMed2005

[Acute left ventricular rupture and cardiac tamponade caused by blunt trauma; report of a case].

It is difficult to save patients with acute left ventricular rupture and cardiac tamponade caused by blunt trauma. A 67-year-old man hospitalized due to sustained multiple blunt trauma. The systolic blood pressure was 40 mmHg. Chest computed tomography (CT) and ultrasonic echocardiography revealed cardiac tamponade. Abdominal CT indicated left renal contusion. Pericardial drainage via the subxiphoid approach drew about 1,000 ml of blood from the pericardial sac, which only transiently increased blood pressure. Median sternotomy and subsequent pericardiotomy revealed pulsatile bleeding jet through a laceration of about 2.0 cm long in the left ventricle near the first diagonal branch. After complete digital compression, the portion was covered by a biological tissue adhesive/sealant sheet (TachoComb), which completely suppressed bleeding. The postoperative course was uneventful. He was discharged from the hospital on the 20th day after the operation.

Acute Disease↗

PubMed2005

[Mature teratoma combined with schizophrenia: report of a case].

A 20-year-old woman was admitted to another hospital due to schizophrenia in July 2003. The patient felt chest pain and palpitation in August, and she was referred to our hospital. Chest computed tomography (CT) showed a mass in the left thoracic cavity and a pleural/pericardial effusion. Since general condition did not improved in spite of aggressive supportive treatment, surgical treatment was chosen. An operation was performed via median sternotomy in September. The tumor was found to have adhered firmly to the surrounding organs. Pericardial fenestration was performed; then the tumor was resected with the left phrenic nerve due to tight adhesion. The patient received respiratory support in the intensive care unit for 5 days after surgery, uneventfully. Twenty-three months after surgery, she is surviving and free from schizophrenic symptoms without medication.

Adult↗

PubMed2004

Transcriptome of mouse uterus by serial analysis of gene expression (SAGE): comparison with skeletal muscle.

The aim of this study was to identify the transcriptome of the normal mouse uterus by Serial Analysis of Gene Expression method. mRNA was extracted from the uterus and also from the gastrocnemius muscle of mice. Short sequences (tags), each one usually corresponding to a distinct transcript, were isolated and concatemerized into long DNA molecules which were cloned and sequenced. We detected 44,484 tags for the uterus and 42,518 tags for the muscle, representing 14,543 and 14,958 potential transcript species, respectively. Seventy-five and sixty-nine genes were expressed at more than 0.1%, thus corresponding to 37 and 34% of the mRNA population detected in the respective tissues. In both cases, the most highly expressed genes are especially involved in muscle contraction, energy metabolism, and protein synthesis. Compared to skeletal muscle, some differentially expressed genes in the uterus are likely to correspond to its specific reproductive functions. The majority of these genes remain to be characterized. More than 70% of the different tags detected in the uterus did not match any sequence in the public databases and can represent novel or poorly identified genes. This study is the first quantitative description of the transcriptome of the uterus.

Animals↗

PubMed2004

Effect of tacrolimus and cyclosporine on renal microcirculation and nitric oxide production.

OBJECTIVES: Cyclosporine (CSA) and tacrolimus (TAC) frequently induce nephrotoxicity and similar pathologic changes. Acute CSA-induced nephrotoxicity has been reported to be mediated by activation of vasoconstrictors such as endothelin. The purpose of the present study was to investigate the acute effects of TAC and CSA on the renal microcirculation and upon a vasodilator such as nitric oxide (NO) production. METHODS: Renal blood flow (RBF) in the microcirculation was measured by a Laser Doppler flow meter in uninephrectomised rats. RBF, mean arterial pressure (MAP), and renal vascular resistance (RVR) were measured in the following groups: (a) TAC (0.1 to 2.0 mg/kg/h, n = 3 approximately 6); CSA (20 and 50 mg/kg/h, n = 5); (b) L-NAME (10 mg/kg), an NO synthase inhibitor, 8 minutes prior to TAC (0.5 and 1.5 mg/kg/h, n = 5), or CSA (20 and 50 mg/kg/h, n = 5). Stable NO end-products, serum NO(2) and NO(3), were measured by the Griess method (n = 5). RESULTS: None of the parameters were changed by TAC alone, whereas TAC with L-NAME significantly reduced RBF (-28 +/- 7%) and increased RVR (46 +/- 17%) in a dose-dependent manner. CSA alone significantly reduced RBF (-37 +/- 6%) and increased RVR (69 +/- 22%) without any changes in MAP. The effects of CSA were enhanced by L-NAME. Serum concentration of NO(2) + NO(3) was significantly reduced by both L-NAME alone and CSA (50 mg/kg) (P < .05), while there were no changes with TAC (1.5 mg/kg). CONCLUSIONS: Blockade of NO production enhance the vasoconstrictive effect of CSA, and unmasked such an effect of TAC. These results suggest that the nephrotoxicity of CSA and TAC may involve the NO system.

Animals↗

PubMed2004

Current research on acute phase proteins in veterinary diagnosis: an overview.

The acute phase proteins (APP) are a group of blood proteins that contribute to restoring homeostasis and limiting microbial growth in an antibody-independent manner in animals subjected to infection, inflammation, surgical trauma or stress. In the last two decades, many advances have been made in monitoring APP in both farm and companion animals for clinical and experimental purposes. Also, the mechanism of the APP response is receiving attention in veterinary science in connection with the innate immune systems of animals. This review describes the results of recent research on animal APP, with special reference to their induction and regulatory mechanisms, their biological functions, and their current and future applications to veterinary diagnosis and animal production.

Acute-Phase Proteins↗

PubMed2004

Antigenic cross-reactivity and sequence homology between Actinobacillus actinomycetemcomitans GroEL protein and human fibronectin.

The immunologic cross-reactivity between human fibronectin and Actinobacillus actinomycetemcomitans GroEL was examined. Analyses by SDS-PAGE/Western immunoblotting and ELISA showed that a polyclonal antibody directed against the purified GroEL protein of A. actinomycetemcomitans, but not against the Escherichia coli GroEL, cross-reacts with human fibronectin. No antigenic cross-reactivity was observed between anti-A. actinomycetemcomitans GroEL antibody and type IV collagen, another important constituent of the basement membrane. A comparative analysis of the amino acid sequences of A. actinomycetemcomitans GroEL and human fibronectin revealed eight instances of four-amino acid sequence homology between the two proteins. Six of these tetrapeptide sequences were also shared with E. coli GroEL, suggesting that the remaining two tetrapeptides, GQLI (Glycine-Glutamine-Leucine-Isoleucine) and TGLE (Threonine-Glycine-Leucine-Glutamic acid), may be associated with the epitope that the anti-A. actinomycetemcomitans GroEL antibody specifically recognizes. Reactivity between TGLE, but not GQLI, with anti-A. actinomycetemcomitans GroEL antibody was confirmed by a biospecific interaction analysis using a biosensor technology. Although additional investigations are required, the observed phenomenon may lead to an autoimmune response and thus contribute to tissue destruction during periodontitis.

Aggregatibacter actinomycetemcomitans↗