Biomedical subjects

Y Suda

Publications and source records attributed to Y Suda.

At least 19 recordsLinked to original sources

PubMed2001

Surgically treated aortic root aneurysm following aortic valve replacement.

A 65-year-old man with aortic regurgitation underwent aortic valve replacement with a St. Jude Medical prosthetic valve about 6 years ago. At that time, the aortic root was slightly dilated at about 40 mm in diameter and the ascending aorta was within the normal range. This year, the man was diagnosed with an aortic root aneurysm in regular follow-up echocardiography. Chest-enhanced computed tomography and chest aortography at our hospital demonstrated a pear-like aortic root aneurysm about 60 mm in diameter. Elective operation for the aortic root aneurysm was conducted September 29, 1999, based on the Bentall procedure. Composite graft replacement with coronary reconstruction was conducted using a 28-mm Hemashield prosthetic graft and a 23-mm St. Jude Medical prosthetic valve under cardiopulmonary bypass. An 8-mm Hemashield graft was interposed on the left main coronary artery and the right coronary artery was directly anastomosed using a Carrel patch method. The postoperative course was uneventful and post-operative examination demonstrated good surgical results. Histological findings of the aortic aneurysm wall showed cystic medial necrosis. Surgical cases of aortic root aneurysm after aortic valve replacement are rare, but serious complications with the possibility of rupture or dissection warrant surgical intervention.

Aged↗

PubMed2001

Coexistence of lung cancer and hamartoma.

We present a rare case of a synchronous primary lung cancer adjacent to a hamartoma. A 71-year-old woman was admitted with congestive heart failure due to acute myocardial infarction. A chest radiogram on admission showed pulmonary edema with a tumor shadow in the right upper lung field. Because histological diagnosis was not obtained preoperatively, a wedge resection of the lung was conducted using video-assisted thoracoscopic surgery. The histopathological examination confirmed the coexistence of an adenocarcinoma with a chondromatous hamartoma. Right upper lobectomy was performed followed by excision of the mediastinal lymph nodes. Although hamartoma is generally considered to be a benign neoplasm, there have been several reports of increased risk to lung cancer in patients with a chondromatous hamartoma. Therefore, we recommend that patients with a hamartoma should be submitted to a complete evaluation and to regular follow-up, considering the risk to associated synchronous malignancy.

Adenocarcinoma↗

PubMed2001

Outcome of patients with non-Hodgkin's lymphoma of the stomach after gastrectomy: clinicopathologic study and reclassification according to the revised European-American lymphoma classification.

BACKGROUND: The best treatment for patients with non-Hodgkin's lymphoma (NHL) of the stomach is still uncertain. The revised European-American lymphoma (REAL) classification has helped to define new, potentially more appropriate classification schemes for gastric lymphomas. METHODS: Fifty-one resected gastric lymphomas were reclassified according to the REAL classification, and the efficacy of multimodal treatment was examined retrospectively. The principal treatment plan consisted of: (1) surgical resection of the stomach with lymph node dissection, followed by (2) systemic chemotherapy, mainly using the cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) regimen. RESULTS: According to the Ann Arbor classification, 27 patients had stage IE, 19 had stage IIE, and 5 had stage IV NHL. Using the REAL classification, we diagnosed diffuse large B-cell lymphoma (DLBL) in 23 patients, marginal zone B-cell (low-grade mucosa-associated lymphoid tissue [MALT]-type) lymphoma in 22, follicle center lymphoma in 4, mantle cell lymphoma in 1, and peripheral T-cell lymphoma in 1 patient. Nine of the 51 patients relapsed, and 8 patients with DLBL died of cancer. Survival rates at 5 years after surgery were 96.0% for stage IE, 83.3% for stage IIE, and 87.0% for all patients. Univariate analysis indicated that the tumor histology (according to the REAL classification), depth of invasion, degree of nodal involvement, Ann Arbor staging, and chemotherapy had an impact on patient outcome (P = 0.0018; P = 0.0002; P = 0.0308; P = 0.0016, and P = 0.0118, respectively). CONCLUSIONS: These data reveal that gastric NHL, especially of the low-grade MALT-type, often remains localized and has a good prognosis after surgery. The REAL classification was useful for classifying new categories of NHL, including the MALT-type, in the clinical setting, and for determining the optimal treatment modality for gastric NHL.

Female↗

PubMed2001

Roles of the anterior cruciate ligament and the medial collateral ligament in preventing valgus instability.

Both the medial collateral ligament (MCL) and the anterior cruciate ligament (ACL) are reported to prevent valgus instability of the knee. In this study, the anatomical mechanisms by which these ligaments prevent valgus instability were experimentally investigated. The valgus rotation angle and the magnitude of the medial joint space opening were measured in six cadaveric knees, using biplanar photography before and after the MCL and/or the ACL were severed. A significant increase in the valgus rotation angle and a large medial joint space opening were observed when the MCL was severed. An increase in the valgus rotation angle was also observed when the ACL was severed, but only a small medial joint space opening was present. The increase in the valgus rotation angle after ACL severance was nearly parallel to the increase in the internal rotation of the tibia. Thus, we concluded that both ligaments function to prevent valgus instability, but that the anatomical reasons for their function are different. The MCL prevents valgus instability by stopping an opening in the medial joint space. The ACL, on the other hand, prevents the internal rotation of the tibia. When the ACL is severed, the internal rotation increases, and causes the valgus rotation angle to also increase, despite the presence of only a small medial joint space opening.

Adult↗

PubMed2001

Partial median sternotomy as a minimal access for off-pump coronary artery bypass grafting: feasibility of the lower-end sternal splitting approach.

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) can be performed in several ways using a minimally invasive approach (MIDCAB). Using the left anterior small thoracotomy (LAST) approach, only the LAD can be grafted. To expand the indications for MIDCAB from single-vessel disease to double-vessel disease, we have used a partial sternotomy without a transverse cut, namely, the lower-end sternal splitting (LESS) approach. Through this approach, the LAD and RCA can be revascularized by means of a single small incision without the risk of damaging the tissue around the intercostal space during harvesting of ITA when the sternum is transversely divided. The purpose of this study was to demonstrate the feasibility and safety of this technique. METHODS: Between November 1999 and November 2000, a total of 22 patients underwent MIDCAB through a lower midline skin incision from the fourth intercostal space to the xiphoid process with longitudinal division of the lower half sternum up to the 3rd rib, without either a T- or reversed L-shaped division of the sternum. Of the patients, 14 had LAD disease only, 5 had both LAD and RCA disease, 2 had RCA disease only, and 1 had left main trunk disease. Two of the operations were of redo coronary artery bypass grafting. The mean age was 69.5 +/- 6.1 years (range 58 to 77 years). RESULTS: The mean length of the skin incision was 8.5 +/- 1.4 cm (range 7 to 12 cm). No hospital death or morbidity was observed. All patients had arterial conduits: LIMA in 20 patients, RIMA in 3, RGEA in 4, and RA in 1. The mean number of grafts per patient was 1.3 +/- 0.6 (range 1 to 3). No blood transfusion was required perioperatively. The patency rate was 96%. All patients were in New York Heart Association class I and no wound complications or postoperative pain occurred during follow-up. CONCLUSIONS: Our experience demonstrates that the LESS approach for MIDCAB is technically feasible for revascularizing not only the LAD but also the RCA system, with the same small incision using IMA and GEA. It can be used with excellent cosmetic results and safety. Although our experience is limited, we conclude that this less invasive surgical technique can be used as an alternative approach for MIDCAB in patients with LAD or RCA disease.

Aged↗

PubMed2001

Changes in ultra-low and very low frequency heart rate variability after coronary artery bypass grafting.

This study was performed to assess the effects of coronary artery bypass grafting (CABG) on the ultra-low (ULF) and very low (VLF) frequency components of heart rate variability (HRV). Forty-nine CABG patients (aged from 38 to 77 years) were examined by 24-h ambulatory electrocardiographic (AECG) monitoring, both preoperatively and 4 weeks after CABG. HRV spectral components were obtained by maximum entropy method analysis. Then the ULF, VLF, low frequency (LF), high frequency (HF) and total frequency (TF) components were compared before and after CABG. The average 24-h heart rate increased significantly after CABG (69+/-11.5 vs 82.9+/-10.9 beats per minute [bpm], P < 0.0001). The power of the ULF, VLF, and LF spectral components showed a decrease after surgery (2,859.9 vs 1,601.2 ms2, P<0.0001, 1,215.0 vs 572.3 ms2, P<0.0001, and 260.3 vs 125.9 ms2, P< 0.002, respectively), but the HF power did not show any significant change (98.7 vs 125.9 ms2, NS). Analysis of the normalized ratio of the ULF component (ULF/TF ratio) revealed a significant increase postoperatively (0.6496+/-0.0931 vs 0.7003+/-0.1338, P < 0.0001), but the VLF/TF and LF/TF ratios decreased after CABG (from 0.2671+/-0.0689 to 0.2040+/-0.0832, P< 0.0001 and from 0.0568+/-0.0290 to 0.0429+/-0.0232, P< 0.0088, respectively). In contrast, there was no significant alteration in the HF/TF ratio. These results suggest that recovery of cardiac autonomic activity is delayed after surgery. However, improvement of the ULF/TF ratio, one of the prognostic indicators for patients with cardiac disease, should be related to the relief of myocardial ischemia by CABG.

Aged↗

PubMed2001

Structural elucidation of a capsular polysaccharide from a clinical isolate of Bacteroides vulgatus from a patient with Crohn's disease.

The structure of a capsular polysaccharide (CPS) from a clinical isolate of Bacteroides vulgatus was elucidated. B. vulgatus IMCJ 1204 was isolated from feces of a patient with Crohn's disease. CPS was prepared by phenol/water extraction of the bacterial cells followed by hydrophobic interaction chromatography and then gel filtration chromatography of the extract. The structure of CPS was determined by chemical analysis and NMR spectroscopy including DQF-COSY, TOCSY, ROESY, HSQC-TOCSY, HMQC and HMBC to be a polysaccharide composed of the following repeating unit: -->3)beta-D-Glcp(1-->6)[alpha-D-GalpNAc(1-->2)beta-D-Galp(1-->4)]beta-D-GlcpNAc(1-->3)alpha-D-Galp(1-->4)beta-D-Manp(1-->.

Bacterial Capsules↗

PubMed2001

Changes in occlusal state of patients with mandibular prognathism after orthognathic surgery: a pilot study.

This study examined the occlusal state of patients with mandibular prognathism and compared it with that of adults with normal occlusion (controls). It also examined changes in occlusal state after orthognathic operations in these patients. The values of occlusal contact area and bite force in patients before operation were significantly lower than in controls, and occlusal pressure in patients was higher than in controls. The occlusal contact area and bite force of the patients 1 month after the operation had decreased to below preoperative values. These values 12 months after the operation had increased by 2.0 and 1.8 times in women and 1.4 and 1.4 times in men, respectively, compared with preoperative values. However, absolute values remained extremely low compared with those of controls. In contrast to the above, occlusal pressure reached its maximum value 1 month after the operation and at 12 months it was close to the value for controls.

Adult↗

PubMed2001

Proper use of MR imaging in internal derangement of the knee (orthopedic surgeon's view).

MR imaging of the knee is a highly accurate examination in terms of the detection of meniscal tears and cruciate ligament ruptures among internal derangement of the knee. The overall accuracy in more than 2000 published cases reached nearly as high as 90% in meniscal tears, and 94% in anterior cruciate ligament (ACL) and 99% in posterior cruciate ligament (PCL) ruptures. Furthermore, the negative predictive value of the knee MR imaging, the number of true negative examination results divided by the numbers of true negative plus false-negative examination results, reaches almost 100% because of its very low false-negative rate. Therefore, from the orthopedic surgeon's point of view, even though the medical cost becomes a great concern, MR imaging has prime importance in the diagnosis of the internal derangement of the knee.

Anterior Cruciate Ligament Injuries↗

PubMed2001

Heparin modulates integrin function in human platelets.

PURPOSE: Heparin binds to human platelets and can cause activation and aggregation, although the mechanisms are unknown. To determine how heparin alters platelet function, we identified platelet-binding sites for heparin and measured heparin's influence on the function of platelet integrin alpha(IIb)beta(3) (glycoprotein IIb/IIIa). METHODS: Photoaffinity cross-linking and affinity chromatography experiments were performed to identify platelet membrane proteins that bind heparin. Heparin's effect on fibrinogen binding to platelets was measured with a radioligand-binding assay. The translocation to the cytoskeleton of Rap2, a guanosine triphosphate-binding protein, was measured from platelets aggregating in response to heparin and other agonists. RESULTS: Cross-linking and affinity chromatographic experiments positively identified the integrin alpha(IIb)beta(3) as a heparin-binding site. Heparin aggregation was calcium dependent. Low concentrations of unfractionated porcine mucosal heparin (2-5 U/mL) significantly increased fibrinogen I 125 binding to activated platelets, whereas higher doses did not. Heparin-mediated platelet aggregation was completely blocked by GRGDS peptide (5 mmol/L), a competitive inhibitor of fibrinogen binding, and was blocked by EDTA (2 mmol/L), which dissociates the functional integrin complex. Aggregation was associated with Rap2 translocation to the cytoskeleton, a sign of outside-in signaling. CONCLUSIONS: Heparin binds to the alpha(IIb)beta(3) integrin in vitro and ex vivo, and heparin increases fibrinogen binding to the integrin. Heparin-mediated aggregation requires an intact integrin and ligand and leads to Rap2 translocation to the cytoskeleton-an outside-in signal of ligand engagement. Heparin may directly modulate platelet integrin function, most likely through direct binding and modulation of integrin function.

Binding Sites↗

PubMed2001

A novel method to study contraction characteristics of a single cardiac myocyte using carbon fibers.

To facilitate cardiac muscle research, we developed a novel method by which the force and length of a single ventricular myocyte can be recorded with a pair of carbon graphite fibers attached firmly to both ends. One fiber was stiff, whereas the other fiber was compliant to allow the recording of force and shortening during twitch contractions. The image of the compliant carbon fiber was projected onto a pair of photodiodes, and their output was fed to a piezoelectric transducer after variable amplifications to alter the effective compliance of the carbon fiber. Thus contraction of the myocyte was induced under virtually isometric conditions as well as under auxotonic conditions. We obtained a bell-shaped relation between the compliance under an auxotonic load and the work output of the myocyte, which was directly related to myocyte performance in the heart. Because it is easy to attach myocytes to the experimental apparatus, the present method would allow us to study cardiac muscle mechanics at the cellular and molecular levels.

Animals↗

PubMed2001

Emx2 directs the development of diencephalon in cooperation with Otx2.

The vertebrate brain is among the most complex biological structures of which the organization remains unclear. Increasing numbers of studies have accumulated on the molecular basis of midbrain/hindbrain development, yet relatively little is known about forebrain organization. Nested expression among Otx and Emx genes has implicated their roles in rostral brain regionalization, but single mutant phenotypes of these genes have not provided sufficient information. In order to genetically determine the interaction between Emx and Otx genes in forebrain development, we have examined Emx2(-/-)Otx2(+/-) double mutants and Emx2 knock-in mutants into the Otx2 locus (Otx2(+/Emx2)). Emx2(-/-)Otx2(+/-) double mutants did not develop diencephalic structures such as ventral thalamus, dorsal thalamus/epithalamus and anterior pretectum. The defects were attributed to the loss of the Emx2-positive region at the three- to four-somite stage, when its expression occurs in the laterocaudal forebrain primordia. Ventral structures such as the hypothalamus, mammillary region and tegmentum developed normally. Moreover, dorsally the posterior pretectum and posterior commissure were also present in the double mutants. In contrast, Otx2(+/Emx2) knock-in mutants displayed the majority of these diencephalic structures; however, the posterior pretectum and posterior commissure were specifically absent. Consequently, development of the dorsal and ventral thalamus and anterior pretectum requires cooperation between Emx2 and Otx2, whereas Emx2 expression is incompatible with development of the commissural region of the pretectum.

Animals↗

PubMed2001

[Inferior mini-sternotomy for off-pump CABG using bilateral internal thoracic arteries].

Case 1: A 72-year-old woman with effort angina underwent coronary artery bypass grafting. A preoperative coronary angiogram showed 90% stenosis in the proximal main RCA, and total occlusion in the proximal LAD, distal of which was an area well supplied by collaterals from the RCA. This patient had previously undergone right upper lobectomy due to lung cancer. With a skin incision of 8 cm, the LITA was inserted into the LAD and the RITA was inserted into the mid RCA through an inferior mini-sternotomy while the heart was beating. Case 2: A 69-year-old man with effort angina underwent CABG. A preoperative coronary angiogram showed 90% stenosis in the proximal main RCA, 75% stenosis in the PDA and total occlusion in the proximal LAD, distal of which was an area well supplied by collaterals from the RCA. With a skin incision of 11 cm, the LITA was inserted into the LAD, the RITA into the mid-RCA and the radial artery graft attached to the RITA was grafted to the PDA through an inferior mini-sternotomy while the heart was beating. In both cases, the sternum was not cut transversely in order to prevent injury to the ITAs and pseudo-joint formation. With the use of this technique, exposure of the LAD and RCA was excellent. Postoperative recovery in both patients was uneventful and postoperative angiograms revealed widely patent grafts. This technique was very useful when performing off-pump CABG using bilateral ITAs.

Aged↗

PubMed2001

[Lower-end sternal splitting (LESS) approach as a new strategy for minimally invasive off-pump CABG].

There are several ways to perform off-pump coronary artery bypass grafting (OPCAB) using a minimally invasive method. Currently, one of the most commonly used approaches is left anterior small thoracotomy (LAST). However, using this approach, only the LAD can be grafted. We have employed a partial sternotomy without a transverse cut, namely, the lower-end sternal splitting (LESS) approach for OPCAB. Through this approach, the LAD and RCA can be revascularized via a single small incision without the risk of damaging the tissue around the intercostal space when the sternum is transversely divided. Since November 1999 to September 2000, we have applied OPCAB through LESS approach in 17 patients. Mean age was 70.0 + 5.4 years (range 58-77), and 13 were men. Mean length of the skin incision was 8.6 + 1.2 cm (range 8-11). No hospital death or morbidity was observed. No patient required blood transfusion. All had arterial conduits: LITA-LAD, in 11; LITA-LAD, RITA-RCA, in 1; LITA-LAD, GEA-PDA, in 2; LITA-LAD, RITA-RCA, RITA-RA-PDA, in 1; and GEA-PDA, in 2. All underwent postoperative coronary angiography, and the patency rate was 95.5%. Our experience demonstrates that the LESS approach for OPCAB is technically feasible and can be used with excellent cosmetic results and safety. Although experience is limited, this less invasive surgical technique can be used as an alternative approach for MIDCAB in patients with LAD and/or RCA disease.

Aged↗

PubMed2001

Examining the effect of intervention to nutritional problems of the elderly living in an inner city area: a pilot project.

OBJECTIVE: To examine the effect of interventions provided to home-delivered meal service recipients living in an inner city neighborhood for the purpose of improving their nutritional conditions. DESIGN: Intervention study. SETTING AND PARTICIPANTS: Both the Study Group (42 seniors) and the Control Group (39 seniors), all of whom are over 60 years old, received home delivered meal services. In addition, only the Study Group received the following services through the trained neighborhood residents: 1) health education, 2) referrals to other community resources for unmet health needs, and 3) follow-up services to assure that the health problems were addressed appropriately. The nutritional condition, depression and cognitive status of the Study Group were assessed by medical staff before and after the six-month intervention. The same assessments were conducted to the Control Group with the same interval. Data was analyzed using ANOVA (repeated). MEASUREMENTS: MNA, GDS, and MMSE. RESULTS: Compared to the Control Group, the nutritional condition (p=0.052) and depression (p=0.02) of the Study Group were improved, while no significant difference was observed in their cognitive status. CONCLUSION: A combination of interventions by medical professionals and by trained neighborhood residents seemed to be an effective strategy to approach nutritional problems of seniors living in inner city areas.

Aged↗

PubMed2001

Chemical structure and biological activity of a lipid A component from Helicobacter pylori strain 206.

The chemical structure of a lipid A, which was obtained as a minor component from lipopolysaccharide of Helicobacter pylori strain 206-1, was determined to be a glucosamine beta-(1 -6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid, (R)-3- hydroxyhexadecanoic acid, and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2-, 3- and 2'-positions, respectively. Compared with the other major lipid A from the same strain, which was previously reported [Suda Y, Ogawa T, Kashihara W et al. Chemical structure of lipid A from Helicobacter pylori strain 206-1 lipopolysaccharide. J Biochem 1997; 121: 1129--1133], the structure was very similar with one exception. An (R)-3-hydroxyhexadecanoic acid was present at the 3-position of the novel lipid A component. The structure is apparently identical to one of the proposals by Moran et al. [Moran AP, Lindner B, Walsh EJ. Structural characterization of the lipid A component of Helicobacter pylori rough- and smooth-form lipopolysaccharides. J Bacteriol 1997; 179: 6453--6463], who concluded the same structure as the so-called major lipid A from the H. pylori strain NCTC 11637 but without isolating a homogeneous component. The endotoxic properties and pro-inflammatory cytokine-inducing activities of this novel tetra-acyl type lipid A were lower than those of previously reported major tri-acyl type lipid A.

Animals↗

PubMed2001

[Coronary artery bypass-grafting using interrupted anastomosis with the U-clip].

For coronary artery anastomosis, the continuous suture technique is generally used because it is easy to perform, there is less anastomotic leakage, and a shorter anastomotic time compared with the interrupted suture technique. However, with this technique there is a potential risk of anastomotic stenosis caused by the purse-string effect, which does not occur with the interrupted suture technique. The U-Clip device was designed to facilitate the interrupted suture technique in coronary anastomosis by eliminating the need for suture management, knot tying, and surgical assistance. The device employs the superelastic properties of nitinol and two components: 1. a needle/suture delivery system, and 2. a detachable nitinol self-closing wire. We used this device successfully for LITA-LAD anastomosis in MIDCAB. When this device is applied to small caliber conduits, such as the internal thoracic arteries and the gastroepiploic artery, the side-to-side anastomosis can reduce the anastomotic leakage more efficiently, since the coronary incision and graft incision can be perfectly matched. The U-Clip facilitates coronary anastomosis by simplifying and decreasing the amount of manipulation and complexity required in minimally invasive CABG procedures. Nitinol technology also has potential in robotic and endoscopic surgical applications.

Aged↗

PubMed2000

Cytokine-inducing macromolecular glycolipids from Enterococcus hirae: improved method for separation and analysis of its effects on cellular activation.

Previously, we showed that several minor macromolecular glycolipids accounting for less than 5% of the lipoteichoic acid (LTA) fraction from Enterococcus hirae ATCC 9790 possess cytokine-inducing activity, whereas the purified LTA does not. In other words, the immunobiological activity of the LTA fraction reported in the 1980s was not attributable to LTA itself, but to other glycolipids coexisting in the fraction. In the present study, we improved the procedure of separation of the active glycolipids and evaluated their effects on cellular activation. The immunobiologically active glycolipids were separated from the crude glycolipid fraction obtained by hot phenol-water extraction of the cells. The total yield of active glycolipids was about fivefold higher than that separated by the previous method. Interleukin-6-inducing activities of the active glycolipids from 1,25-dihydroxy vitamin D(3)-differentiated human monocytic leukemia cells, THP-1, were inhibited by anti-CD14 mAbs in a dose-dependent manner. Macrophages from Toll-like receptor (TLR)-2-deficient or -4-deficient mice completely lacked the ability to produce tumor necrosis factor-alpha on stimulation with active glycolipids. These observations indicated that the cellular activation by the active glycolipids from E. hirae is mediated by CD14 and by both TLR2 and TLR4.

Animals↗