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Taijiro Sueda

Publications and source records attributed to Taijiro Sueda.

At least 55 records · Page 3Linked to original sources
PubMed2005

Genetic analysis of polymorphisms in biologically relevant candidate genes in patients with abdominal aortic aneurysms.

BACKGROUND: Abdominal aortic aneurysms (AAAs) are characterized by histologic signs of chronic inflammation, destructive remodeling of extracellular matrix, and depletion of vascular smooth muscle cells. We investigated the process of extracellular matrix remodeling by performing a genetic association study with polymorphisms in the genes for matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), and structural extracellular matrix molecules in AAA. Our hypothesis was that genetic variations in one or more of these genes contribute to greater or lesser activity of these gene products, and thereby contribute to susceptibility for developing AAAs. METHODS: DNA samples from 812 unrelated white subject (AAA, n = 387; controls, n = 425) were genotyped for 14 polymorphisms in 13 different candidate genes: MMP1(nt-1607), MMP2(nt-955), MMP3(nt-1612), MMP9(nt-1562), MMP10(nt+180), MMP12(nt-82), MMP13(nt-77), TIMP1(nt+434), TIMP1(rs2070584), TIMP2(rs2009196), TIMP3(nt-1296), TGFB1(nt-509), ELN(nt+422), and COL3A1(nt+581). Odds ratios and P values adjusted for gender and country of origin using logistic regression and stratified by family history of AAA were calculated to test for association between genotype and disease status. Haplotype analysis was carried out for the two TIMP1 polymorphisms in male subjects. RESULTS: Analyses with one polymorphism per test without interactions showed an association with the two TIMP1 gene polymorphisms (nt+434, P = .0047; rs2070584, P = .015) in male subjects without a family history of AAA. The association remained significant when analyzing TIMP1 haplotypes (chi 2 P = .014 and empirical P = .009). In addition, we found a significant interaction between the polymorphism and gender for MMP10 ( P = .037) in cases without a family history of AAA, as well as between the polymorphism and country of origin for ELN ( P = .0169) and TIMP3 ( P = .0023) in cases with a family history of AAA. CONCLUSIONS: These findings suggest that genetic variations in TIMP1, TIMP3, MMP10, and ELN genes may contribute to the pathogenesis of AAAs. Further work is needed to confirm the findings in an independent set of samples and to study the functional role of these variants in AAA. It is noteworthy that contrary to a previous study, we did not find an association between the MMP9 (nt-1562) polymorphism and AAA, suggesting genetic heterogeneity of the disease. CLINICAL RELEVANCE: Abdominal aortic aneurysms (AAAs) are an important cardiovascular disease, but the genetic and environmental risk factors, which contribute to individual's risk to develop an aneurysm, are poorly understood. Histologically, AAAs are characterized by signs of chronic inflammation, destructive remodeling of the extracellular matrix, and depletion of vascular smooth muscle cells. We hypothesized that genes involved in these events could harbor changes that make individuals more susceptible to developing aneurysms. This study identified significant genetic associations between DNA sequence changes in tissue inhibitor of metalloproteinase 1 (TIMP1), TIMP3, matrix metalloproteinase 10 (MMP10) and elastin (ELN) genes, and AAA. The results will require confirmation using an independent set of samples. After replication it is possible that these sequence changes in combination with other risk factors could be used in the future to identify individuals who are at increased risk for developing an AAA.

Aortic Aneurysm, Abdominal↗
PubMed2005

Hepatic regeneration promotes engraftment of intraportally transplanted islet cells.

BACKGROUND: With the current donor shortage, future success with islet transplantation is incumbent upon the ability to use single-donor islets. Manipulating the recipient graft environment may allow the use of fewer islets to achieve insulin independence. METHODS: Isolated pancreatic islets from a single donor were intraportally transplanted to streptozotocin-diabetic rats immediately after 70% partial hepatectomy (HxPIT1, n = 12). Plasma glucose concentrations were monitored for 30 days; intravenous glucose tolerance tests and serum insulin concentrations were obtained at the second and fourth weeks; morphologic studies were performed on insulin-immunostained sections of the liver. RESULTS: from HxPIT1 rats were compared to those from rats transplanted with single-donor islet grafts (PIT1, n = 10) and double-donor islet grafts (PIT2, n = 7). Results Hyperglycemia was ameliorated in HxPIT1 and PIT2 rats after transplantation but not in PIT1 rats. Glucose tolerance and insulin secretion in the HxPIT1 group were superior to the PIT1 group and equivalent to those in the PIT2 group. Morphologically, the sizes of the grafted islets and individual beta cells from HxPIT1 rats were larger than those from PIT1 rats. CONCLUSIONS: In streptozotocin-diabetic rats, islet transplantation performed in regenerating liver results in improved insulin secretion and serum glucose control, even in the face of a limited number of islets.

Animals↗
PubMed2005

Dynamic cytoplasmic anchoring of the transcription factor Bach1 by intracellular hyaluronic acid binding protein IHABP.

Bach1 functions as a transcriptional repressor of heme oxygenase-1 (HO-1) and the beta-globin genes. The enhancer regions of these genes contain multiple Maf recognition elements (MAREs) to which Bach1 can bind. Previous studies have shown that increased levels of heme and cadmium induce the nuclear export of Bach1, resulting in cytoplasmic accumulation. By means of a yeast two hybrid screening using Bach1 as bait, we identified the intracellular hyaluronic acid binding protein (IHABP) as a potential regulator of Bach1. IHABP is a microtubule-associated protein that may regulate the organization of the cytoskeletal network. A series of domain analyses revealed that a region of Bach1 previously implicated in cytoplasmic accumulation was necessary for IHABP-binding. A C-terminal region of IHABP was necessary for Bach1-binding. Overexpressed Bach1 colocalized with IHABP in the cytoplasm, forming fiber-like structures on microtubules. Fluorescence recovery after photobleaching (FRAP) analysis revealed a dynamic nature of the Bach1-IHABP interaction in living cells. The repression of HO-1 reporter activity by Bach1 was attenuated by co-transfecting IHABP in a dose-dependent manner. Moreover, the overexpression of IHABP induced the endogenous HO-1 gene in NIH3T3 cells. The overall results suggest that IHABP regulates the subcelluar localization of Bach1 in order to fine-tune transactivation of Bach1 target genes such as HO-1.

Animals↗
PubMed2005

Extrathoracic subclavian venipuncture under ultrasound guidance.

BACKGROUND: Cardiac pacemaker and defibrillator leads are inserted through extrathoracic subclavian venipuncture using ultrasound (US) guidance, but there can be complications. The purpose of this study was to investigate a safer and improved implanting procedure. METHODS AND RESULTS: Venipuncture guided by US with a 7.5 MHz convex transducer was performed to implant 32 leads in 18 patients. US enabled identification and location of the vein and needle tip during puncture and clarified the reasons for unsuccessful venipuncture. Venipuncture was successful on the second attempt or within 2 min in 90.6% (29/32) and 84.4% (27/32) of lead placements, respectively, although the vein was small (mean, 7.8 mm), deep (mean, 22.7 mm), and required a large angle of entry (mean, 52.4). The subclavian artery or lung was adjacent to the vein in 50.0% and 27.8% of cases, respectively. The flexible wall of the vein interfered with the penetration of the needle in 33.3% of cases. It was often difficult to locate the needle tip because of poor visualization. CONCLUSIONS: Ultrasound guidance of subclavian venipuncture enables a safe and time-saving procedure by visualizing not only the needle but also the vein and surrounding structures, although further modifications of the needle are needed for better visualization.

Defibrillators, Implantable↗
PubMed2005

Novel Doppler technique to assess systemic vascular resistance: the snuffbox technique.

BACKGROUND: To explore an alternative to the systemic vascular resistance index (SVRI) for monitoring peripheral circulation in patients in the intensive care unit (ICU), the resistive index (RI) in the upper extremity arteries was measured by using surface Doppler ultrasound. METHODS AND RESULTS: The correlation between RI and vascular resistance was assessed in vitro using a vessel phantom in a Donovan-type mock circulation system. In addition, 15 ICU patients who had undergone open-heart surgery were studied. Mean arterial pressure, central venous pressure and cardiac output were measured 30 times at 10 min intervals after patients returned to the ICU following surgery, and the SVRI was calculated from these parameters. At the same time points, 3 parts of the upper extremity arteries (brachial artery in the cubital fossa (BA), radial artery at the wrist (RA), and radial artery at the anatomical snuffbox (SB)) were scanned by Doppler ultrasound, and the resistance index (RI) for each artery region was calculated. In vitro, RI increased with higher vascular resistance, exhibiting a significant correlation (r = 0.982, p < 0.0001). In vivo, the average incidence angles at the BA and RA were larger than 60 degrees , while that at the SB was only 11.5+/-10.8 degrees. The overall correlation between SVRI and RI for all patients was not significant for the BA or RA, but was significant for the SB (p < 0.0001). In individual patients, the correlation of SVRI with RI at the BA or RA was significant in 3 patients only, whereas significant correlation for the SB was observed in all patients. Doppler waveform analysis at the SB revealed diastolic flow reversal with increased SVRI. CONCLUSIONS: Measurement at the SB provides an ideal ultrasound incidence angle for the measurement of blood flow velocity. Hence, RI measured in this way may serve as an indicator of peripheral vascular resistance, and may be effective for the evaluation of peripheral circulatory disturbance.

Aged↗
PubMed2005

Intracellular cytokine patterns of peripheral blood T cells as a useful indicator of activeness of Crohn's disease.

Recently, the alteration of peripheral T cells has become a focus of attention in research on Crohn's disease (CD). To examine the characteristics of peripheral T cells in CD patients, we analyzed the expression of a memory T cell marker (CD45RO(Bright)CD3+) and the cytokine production by peripheral helper and cytotoxic T cells in patients with CD. With the use of monensin to prevent the secretion of cytokines under stimulation, we measured the count of intracellular cytokine-positive cells for production of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-2, IL-4, IL-6, IL-10, and granulocyte-macrophage colony stimulating factor (GM-CSF) in the peripheral T cell population using flow-cytometry. The counts of lymphocytes, T cells, and helper T cells in patients with CD were significantly lower than in normal volunteers. Although no difference in the counts of lymphocytes, total T cells, helper and cytotoxic T cells was observed, the counts of intracellular cytokine producing helper T cells in IFN-gamma, TNF-alpha or GM-CSF were significantly higher in active cases than in quiescent cases. These results suggest that stable CD patients are immunosuppressive, and activation of some kinds of T-cells, especially Th1-associated cytokine producing T-cells, correlate with disease progression. Th1-associated cytokine analysis of peripheral T cells may be one of the useful markers to evaluate the activeness of Crohn's disease.

Adult↗
PubMed2005

Attenuation of telomerase activity by hammerhead ribozymes targeting human telomerase RNA and telomerase reverse transcriptase in pancreatic carcinoma cells.

In cancer gene therapies, it is ideal to target tumor-specific genes. Since telomerase is activated in almost all cancer cells but not most somatic cells, it is considered as one of the favorite targets for cancer gene therapies. Ribozymes are catalytic RNA molecules with site-specific endoribonuclease activity. In the present study, we designed hammerhead ribozymes against human telomerase RNA (hTR) and human reverse transcriptase subunit (hTERT) to evaluate their effect on the attenuation of telomerase in the pancreas cancer cell line, PK-8. Hammerhead ribozyme targeting hTR depressed the level of telomerase activity in PK-8 cells. pRc-hTR vector with ribozyme targeting hTR and pRc-hTERT vector with ribozyme targeting hTERT mRNA were transfected into PK-8 cells and depressed telomerase activity and target RNA, but in pRc-hTR transfectant, hTERT mRNA expression was slightly upregulated and in pRc-hTERT transfectant hTR expression was also slightly upregulated. These findings indicate the co-regulation of hTR and hTERT mRNA expression in cancer cells. Extrachromosomal replicational vector, pCEP4, containing ribozyme targeting hTERT mRNA showed the most effective inhibition of telomerase activity, suggesting that the continuous effect of ribozyme is necessary to inhibit telomerase activity. Since the level of hTERT mRNA expression is less than that of hTR expression in cancer cells, ribozyme targeting hTERT mRNA might be a more useful therapeutic strategy for cancer gene therapy. Moreover, the co-regulation of hTR and hTERT mRNA expression in cancer cells to maintain the levels of telomerase activity suggested that the strategy of inhibiting hTERT mRNA and hTR simultaneously has a powerful potential as a gene therapy for targeting human telomerase.

Base Sequence↗
PubMed2005

Echo-guided identification of key lumbar arteries for the spinal cord: preliminary study in the canine model.

Although identification of the key artery that perfuses the spinal cord is essential to avoid occurrence of paraplegia after surgery on the thoracoabdominal aorta, reliable and noncomplicated measures are not yet available. A new method of determining it by using echocardiography with a saline injection into the lumbar artery was evaluated for feasibility and adequacy in a canine model. In two mongrel dogs, the abdominal aorta was opened and saline was directly injected into the lumbar arteries while the spinal cord was visualized by echocardiography through the intervertebral disc. When the echogenic or Doppler signal was detected in the spinal cord, the particular lumbar artery was determined as "positive", or as "negative" when the signal was not detected. After the dog was sacrificed, red resin was injected into the "positive" arteries and blue resin into the "negative" arteries. In the extracted spinal cord, the anterior and posterior spinal arteries were filled with red resin, rather than with blue resin, to indicate that the key arteries were correctly identified. There were multiple "positive" arteries, which were mainly located on the left side and accounted for approximately one-third of the entire lumbar arteries. The "negative" arteries mainly perfused the muscles around the vertebra. Injected resin came out of the adjacent lumbar arteries of the same category, suggesting that communication is present among the positive arteries, but independently of that among the negative arteries. Echo-guided identification of key arteries is technically feasible and correctly determines the key arteries in this preliminary canine model.

Animals↗
PubMed2005

[Non-cardiac surgery for patients with arrhythmia].

Arrhythmia is the most common perioperative cardiac complication during noncardiac surgery. Most perioperative arrhythmia is benign, but fatal arrhythmia can occur, requiring emergency care. Arrhythmia is divided into tachycardia and bradycardia. Both arrhythmias often result in cardiac failure. Ischemic heart disease often causes premature ventricular contraction or ventricular tachycardia. Hypertensive heart disease or valvular heart disease can lead to atrial fibrillation or supraventricular tachycardia. Although patients may not have cardiac disease, hypoxia, hypovolemia, electrolyte disturbance, acidosis, and hypothermia can also cause arrhythmia. Patients with pacemakers or implantable cardiodefibrillators (ICDs) are affected by electric cauterization, which interferes with the sensing and inhibits the pacing of pacemakers as well as ICDs If this occurs, the mode of pacemakers and ICDs must be reset during surgery.

Arrhythmias, Cardiac↗
PubMed2005

[Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2003 and March 2004].

Tendency of isolated bacteria from infections in general surgery during the period from April 2003 to March 2004 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 455 strains including 14 strains of Candida spp. were isolated from 191(75.2%) of 254 patients with surgical infections. Two hundred and thirty-nine strains were isolated from primary infections, and 216 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria and aerobic Gram-negative bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa in this order, and from postoperative infections, E. coli was the most predominantly isolated, followed by P. aeruginosa, E. cloacae, and K. pneumoniae. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. The isolation rate of anaerobic Gram-positive bacteria from primary infections and that of aerobic Gram-positive bacteria from postoperative infections were high in the last several years. In this series, we noticed no vancomycin-resistant Gram-positive cocci, but a few strains of moderately arbekacin-resistant MRSA. Carbapenm-resistant P. aeruginosa was seen in less than 10 per cents. Last year we noticed that there were cefazolin-resistant E. coli producing extended spectrum beta-lactamase, but there was no highly cefazolin-resistant E. coli in this year. In the next series, increase of both anaerobic bacteria and Enterococcus spp. should be carefully followed up.

Anti-Bacterial Agents↗
PubMed2005

[Perioperative care for thoracic surgery with complications in elderly patients].

Perioperative care for high-aged coronary artery bypass grafting (CABG), thoracic aortic aneurysm and lung cancer is discussed. Among them, each disease has their characteristics and complications. Especially, respiratory, cerebral and cardiovascular complications are common in high-aged patients requiring thoracic surgeries. Careful management is mandatory during these surgeries.

Aged↗
PubMed2005

Cold saline injection attenuates motor-evoked potential in the spinal cord by cortical electrical stimulation in the dog.

Changes in the motor-evoked potential of the spinal cord with transcranial stimulation are monitored for spinal cord function during thoracoabdominal aortic aneurysm surgeries. We examined the effects of changes in motor-evoked potential with cold saline injected into the clamped segment of the aorta, and compared the effects to lidocaine and warm saline injection. Eighteen dogs were divided into three groups according to the injected agents: Warm saline group (37 degrees C, 20 ml), Cold saline group (4 degrees C, 20 ml), and Lidocaine group (5.0 mg/kg of lidocaine in 20 ml of warm saline), (n=6, each group). Changes in the peak-to-peak MEP amplitude and the indirect wave (I wave) amplitude were measured during aortic cross-clamping. In the peak-to-peak MEP amplitude, the cold saline and lidocaine groups attenuated to 80% of the control value but were not significantly changed. In the I wave amplitude, the cold saline group showed a significant attenuation 1 min after injection (p<0.0001) and the lidocaine group 4 min after injection (p=0.0230), when compared with the warm saline group. Attenuation of the I wave amplitude in the cold saline group was significantly larger than that in the lidocaine group (p=0.0003). Changes in the I wave amplitude appeared within 4 min in both the cold saline and lidocaine groups. Cold saline injection into the clamped segment of the aorta is a diagnostic procedure for determining presiding critical arteries in the segment without experiencing the pharmacological side effects observed with lidocaine injection.

Animals↗