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S Matsuda

Publications and source records attributed to S Matsuda.

At least 163 records · Page 9Linked to original sources
PubMed1999

A high-fat diet aggravates tubulointerstitial but not glomerular lesions in obese Zucker rats.

BACKGROUND: Despite a large body of evidence that manipulation of dietary fat alters glomerular lesions, reports regarding the effects of dietary fat on tubulointerstitial lesions are limited. Obese Zucker rats (OZR) spontaneously develop glomerular and tubulointerstitial lesions in association with hyperlipidemia. We sought to elucidate the effects of dietary fat on glomerular and tubulointerstitial lesions in OZR versus lean Zucker rats (LZR) and to assess the involvement of macrophages in the development of these lesions. METHODS: We fed LZR and OZR either a low- (1%) or high-fat (20%) diet. After 30 weeks of the specified diet, the creatinine clearance (Ccr) and renal histology as well as plasma lipid concentrations were examined. For morphological evaluation, glomerular sclerosis (GSI) and tubulointerstitial indices (TII) were each determined by a point-counting method. Infiltrating macrophages were stained immunohistochemically using an avidin-biotin complex technique. RESULTS: The high-fat diet increased the plasma low-density lipoprotein concentration in OZR. Both low- and high-fat OZR groups had higher GSI and TII than LZR receiving either diet. The high-fat diet aggravated TII but not GSI or Ccr in OZR; conversely, high fat intake worsened GSI and Ccr but not TII in LZR. Tubulointerstitial macrophages were most prominent in the high-fat OZR group, followed by the low-fat OZR group. Glomerular macrophages were similar in number in all groups. CONCLUSIONS: The manipulation of dietary fat has diverse effects on the kidney. A high-fat diet aggravated macrophage-mediated tubulointerstitial lesions in OZR, whereas in LZR, the diet induced glomerulosclerosis.

Albuminuria↗
PubMed1999

Replication in vitro and cleavage by restriction endonuclease of 5-formyluracil- and 5-hydroxymethyluracil-containing oligonucleotides.

PURPOSE: To investigate the biological consequences of 5-formyluracil (5-foU) and 5-hydroxymethyluracil (5-hmU). MATERIALS AND METHOD: The authors constructed 22-mer oligonucleotides containing a 5-foU or 5-hmU residue at the same sites. The effects of such modifications on the ability to serve as a template for DNA polymerase and on the cleavage by sequence-specific restriction endonuclease were examined. RESULTS: The Klenow fragment of DNA polymerase I and Thermus thermophilus DNA polymerase read through the sites of 5-foU and 5-hmU in the templates. 5-FoU directed the incorporation of dCMP in addition to dAMP opposite the lesion during DNA synthesis. The DNA polymerases incorporated only dAMP opposite the 5-hmU. The substitution of thymine by 5-foU within the recognition site of the restriction endonucleases HincII and SalI inhibited or prevented the cleavage by the enzymes, whereas the enzymes cleaved the 5-hmU-containing oligonucleotides at the same rate as the T-containing oligonucleotides. CONCLUSIONS: These results indicated that the 5-foU-A base pair is less stable than the T-A base pair and that 5-foU can form a base pair with C in addition to A. It was also demonstrated that the oxidation of thymine to 5-hmU does not result in substantial deterioration.

Animals↗
PubMed1999

Reversible photoligation of DNA via 5-vinyldeoxyuridine.

We report a novel non-enzymatic template-directed reversible photoligation of oligodeoxyribonucleotides (ODNs). In this photoligation system, a modified ODN containing 5-vinyldeoxyuridine at 5'-end reacts by photoirradiation at 366 nm with cytosine and thymine at the 3'-end of another ODN in the presence of a complementary template to yield a ligated ODN quantitatively. The ligated ODN can be split site-selectively to regenerate the parent ODN by photoirradiation at 302 nm.

Base Sequence↗
PubMed1999

Knee stability in posterior cruciate ligament retaining total knee arthroplasty.

Anteroposterior knee laxity was evaluated in 14 patients (19 knees) who had posterior cruciate ligament retaining total knee arthroplasty using the Miller Galante I prosthesis. The followup ranged from 87 to 118 months (average, 105.9 months), and the measurements were done using the KT-2000 arthrometer. The mean anteroposterior displacement with the knees with Miller Galante I prostheses was 10.1 mm at 30 degrees flexion and 8.1 mm at 75 degrees flexion. In the 15 knees with Miller Galante I prostheses with flexion greater than 90 degrees, seven had less stability at 75 degrees than at 30 degrees flexion. These knees were considered to have a nonfunctional posterior cruciate ligament, and they had a worse Knee Society score (81.1) than did the other eight knees with Miller Galante I prostheses (89.9). There were four knees in which the flexion was less than 90 degrees. In this study, approximately half of the knees with posterior cruciate ligament retaining total knee arthroplasty did not have good anteroposterior stability in flexion an average of 9 years after surgery.

Aged↗
PubMed1999

Chemokine receptor-usage of clinical HIV-1 isolates obtained from patients with HIV-1 infection in late clinical stages using PHA-blast.

In the present sudy, chemokine receptor-usage of primary HIV-1 isolates was examined using U87-CD4 cells expressing chemokine receptors CCR3, CCR5 and CXCR4. HIV-1 was isolated from the peripheral blood mononuclear cells (PBMC) and/or plasma of eight HIV-1-infected individuals in late CDC-II and CDC-IV clinical stages using PHA-blast prepared from the PBMC of healthy blood donors. The primary HIV-1 isolates from patients in late CDC-II stage rarely infected monocyte-derived macrophages in the present study, whereas most isolates from patients in the CDC-IV stage infected the macrophages. In the experiments using U87-CD4 cells expressing chemokine receptors, the isolates from patients in the late CDC-II stage infected U87-CD4 cells expressing CXCR4, but not U87-CD4 cells expressing CCR5. In contrast, most isolates from patients in the CDC-IV stage infected both U87-CD4 cells expressing CXCR4 or CCR5. The isolates which infected both U87-CD4 cells were supposed to contain dual tropic HIV-1 or a mixture of CXCR4-tropic and CCR5-tropic HIV-1s. Analysis of the deduced amino acid sequence of the V3 region in proviral env gene showed that the V3 region in U87-CD4 cells infected with CXCR4-tropic HIV-1 isolates was largely different from that in the cells infected with CCR5-tropic isolates, but were highly similar to that in cells infected with dual tropic isolates. These results suggest that PHA-blasts may preferentially support the replication of the CXCR4-tropic and dual tropic HIV-1s, and that CXCR4-tropic and dual tropic HIV-1s are also present in peripheral blood from patients in the late stage of the asymptomatic phase.

Amino Acid Sequence↗
PubMed1999

Migration of neutrophils is dependent on mast cells in nonspecific pleurisy in rats.

To determine the role of mast cells in the recruitment of neutrophils and eosinophils, acute nonspecific pleurisy was induced by injecting isologous serum into normal +/+ and mast cell-deficient Ws/Ws rats. In +/+ rats, neutrophil infiltration peaked 4 h after serum administration, followed by influx of eosinophils after 24-48 h. The levels of neutrophil influx after 4 h as well as the activity of myeloperoxidase (MPO) in pleural lavage-cell extract were significantly lower in Ws/Ws rats than in +/+ rats. In contrast, numbers of eosinophils as well as activity of eosinophil peroxidase (EPO) did not differ significantly between Ws/Ws and +/+ rats. For local reconstitution of mast cells, +/+ rat peritoneal mast cells (PMC) or mesenteric lymph node cells (MLNC) as a control were transferred into the Ws/ Ws pleural cavity. Serum injection into animals with PMC transfer 7 days previously triggered augmented neutrophil influx by approximately 4.7-fold as compared to that in MLNC-transferred animals. Mast cells recovered from the pleural cavity of PMC-transferred rats showed histamine contents equivalent to 20% of that of freshly isolated PMC and retained the reactivity to compound 48/80. These results indicated that dependency of neutrophil recruitment on resident mast cells is greater than that of eosinophils in isologous serum-induced pleurisy.

Animals↗
PubMed1999

Incidence and risk factors of benign creatine phosphokinase elevations in chronic psychiatric patients.

There have been few studies focusing on the creatine phosphokinase (CPK) elevations in chronic psychiatric patients. The survey was conducted prospectively to investigate the incidence and risk factors of CPK elevations in chronic psychiatric patients during a 2-year follow-up period. Sixteen of 32 (50%) patients had maximums of more than 230 U/l (upper limit of our normal range) and 7 (22%) patients had maximums of more than 500 U/l. Surprisingly, 4 (13%) patients had maximums of more than 1,000 U/l after exercises such as swimming and walking. Nonetheless, none of the 16 patients with the CPK elevations developed severe conditions such as rhabdomyolysis despite an absence of therapeutic intervention, and their CPK elevations were proven to be benign. According to the path analysis, usual physical activity and neuroleptic doses seemed to underlie CPK elevations directly. The present findings suggest that not a few chronic psychiatric inpatients may have at least one CPK elevation per 2 years. Patients engaging in more physical activity or receiving higher neuroleptic doses are at greater risk of developing such CPK elevations. However, most of these increases are benign, and it is not considered necessary to treat them.

Adult↗
PubMed1999

Angioplasty-bypass surgery combination therapy: case study of an elderly patient with unstable angina and colon cancer.

An 83-year-old man was admitted with refractory unstable angina and severe anemia. Colonofiberscopy revealed hemorrhagic colon cancer in the transverse colon. Coronary angiography showed total occlusion of the right coronary artery (RCA), diffuse, calcified 90% stenosis of the middle portion of the left anterior descending artery (LAD); and fair collaterals from the LAD to the RCA. Coronary revascularization was considered prior to colectomy, but because of the patient's advanced age and hemorrhagic cancer, conventional coronary aorta bypass grafting (CABG) using extracorporeal circulation, as well as coronary stenting requiring antiplatelet therapy, were regarded as inadvisable. Percutaneous transluminal coronary angioplasty (PTCA) for the LAD carried the risk of suboptimal coronary stenting. Thus, the patient was first treated with PTCA for the occluded RCA, followed 7 days later by a left internal thoracic artery graft to the LAD on the beating heart without extracorporeal circulation. The patient was stable thereafter. This approach to coronary revascularization may be suitable for patients for whom anticoagulation or antiplatelet therapy are contraindicated, or when complete revascularization would be difficult with CABG or PTCA alone.

Aged↗
PubMed1999

Investigation of the most effective provocation test for patients with coronary spastic angina: usefulness of accelerated exercise following hyperventilation.

This study sought to compare the clinical usefulness of the hyperventilation plus cold stress test or the hyperventilation combined with accelerated exercise test with other single tests in patients with coronary spastic angina. The study examined 24 patients (23 men, mean age 66 years) with angiographically confirmed coronary spastic angina and less than 50% stenosis. Moreover, none had spontaneous ST segment elevation before the study. Under no medication for at least 24 h prior, 4 procedures were performed from 09.00 h to 11.00 h: (i) a hyperventilation test for 5 min (HV(5)); (ii) HV(5) combined with a cold stress test for the last 2 min (HV(5)+CS(2)); (iii) a treadmill exercise test based on Bruce's protocol (TM(3)); and (iv) a treadmill exercise test accelerated at 1 min intervals according to Bruce's protocol immediately after HV(5) (HV(5)+TM(1)). The rate of appearance of chest pain and ischemia-induced ECG changes due to HV(5)+TM(1) were significantly higher than the other 3 tests. HV(5)+CS(2) was not superior to HV(5) alone. The incidence of provoked ST segment elevation due to HV(5)+TM(1) was higher than with the other 3 procedures. Thus, in patients with coronary spastic angina, no spontaneous ST segment elevation and near normal coronary arteries, HV(5)+CS(2) was no more useful than HV(5) alone. It is recommended that the newly designed HV(5)+TM(1) combination test be used for documenting evidence of ischemia in patients with coronary spastic angina, low disease activity and near normal coronary arteries.

Acetylcholine↗
PubMed1999

Clinical manifestation and survival of patients with idiopathic bilateral atrial dilatation.

We studied the histories of eight patients who lacked clear evidence of cardiac abnormalities other than marked bilateral atrial dilatation and atrial fibrillation, which have rarely been discussed in the literature. From the time of their first visit to our hospital, the patients' chest radiographs and electrocardiograms showed markedly enlarged cardiac silhouettes and atrial fibrillation, respectively. Each patient's echocardiogram showed a marked bilateral atrial dilatation with almost normal wall motion of both ventricles. In one patient, inflammatory change was demonstrated by cardiac catheterization and endomyocardial biopsy from the right ventricle. Seven of our eight cases were elderly women. Over a long period after the diagnosis of cardiomegaly or arrhythmia, diuretics or digitalis offered good results in the treatment of edema and congestion in these patients. In view of the clinical courses included in the present study, we conclude that this disorder has a good prognosis.

Aged↗
PubMed1999

The effect of varus tilt on contact stresses in total knee arthroplasty: a biomechanical study.

The contact stress produced in the tibiofemoral joint from a varus-tilted tibial component was tested in five total knee prostheses. Peak and mean stresses were measured with a digital electronic sensor under compressive load at 15 degrees and 90 degrees flexion. Stresses were measured with the tibial component tilted 0 degrees and 5 degrees in the mediolateral direction. At a 5 degree tilt, the Advantim, the Miller-Galante II, and the Omnifit prostheses, which have a flat configuration on the femoral and tibial surfaces in the coronal plane, had significantly greater stresses than the LCS and the Profix prostheses, which have tibial and femoral components with matching curved surfaces in the coronal plane. These results suggest that the femoral component surface should have a radius of curvature that matches that of the tibial articular surface in the coronal plane to achieve a large contact area even in varus-valgus tilting.

Arthroplasty, Replacement, Knee↗
PubMed1999

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1997). II. Background of patients].

Clinical background was investigated on patients with urinary tract infections (UTIs) from whom 603 bacterial strains were isolated in 9 hospitals during the period from June, 1997 through May, 1998. 1. Distribution of age and sex of patients and type of infections Among males, those with ages less than 50 years were only 12.5%, and those in the 70's were most frequent (33.3%). Among females, those with ages less than 20 years were only 3.4%, and those in the 60's were the most frequent (22.9%). With regard to type of infections, more than a half of infections among males with ages 50 years or older were of complicated types, but most of infections among females were of uncomplicated types, especially those of ages less than 50 years. 2. Ages of patients and types of pathogens Escherichia coli was the most frequently isolated in uncomplicated and complicated UTIs without indwelling catheters. In complicated UTIs with indwelling catheters, Pseudomonas aeruginosa and Enterococcus faecalis had mainly detected, they had no relationship with ages. 3. Effect of antibiotic use on isolation frequencies of pathogens Use of antibiotics decreased pathogens isolated from patients with uncomplicated UTIs drastically (183 isolates before antibiotics compared to 13 after). Even isolated pathogens from patients with complicated UTIs decreased drastically with the use of antibiotics when indwelling catheters were not in use (175 isolates before antibiotics compared to 53 after), but when indwelling catheters were in use, antibiotics slightly decreased (109 isolates before antibiotics compared to 70 after). 4. Surgical procedures and types of causative organisms for UTIs E. faecalis were more isolated when a surgical procedures were used, and E. coli were more isolated when, they were not used in uncomplicated and complicated UTIs without indwelling catheters. In complicated UTIs with indwelling catheters, E. coli and E. faecalis were more isolated when a surgical procedures were used, and P. aeruginosa and Staphylococcus aureus were more isolated when they were not used.

Adult↗
PubMed1999

[Cervicitis].

Explore the source record for details and available documents.

Female↗
PubMed1999

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1997). III Secular changes in susceptibility].

Susceptibilities to various antimicrobial agents were examined for Enterococcus faecalis, Staphylococcus aureus, Echerichia coli, Klebsiella spp., and Pseudomonas aeruginosa that were isolated from patients with urinary tract infections (UTIs) in 9 hospitals during June 1997 to May 1998, and the results were compared with those obtained during the same period in earlier years. 1. E. faecalis The MIC90s of quinolones for E. faecalis isolated from uncomplicated UTIs have changed better state during the latest period. Among E. faecalis strains, those with high susceptibilities to ampicillin (ABPC) and minocycline (MINO) appeared to had decreased during period of 1995-1997, which recovered during the latest period. 2. S. aureus The sensitive strains of S. aureus to imipenem (IPM) and clindamycin (CLDM) had increased during the period of 1996-1997, but those have decreased again during the latest period. 3. E. coli The susceptibilities of E. coli to MINO have been better in the latest period with the MIC90 was ranged from 2 to 4 micrograms/ml. The susceptibilities to quinolones of E. coli isolated from complicated UTIs had decreased during the period of 1995-1997, but those have recovered during the latest period. 4. Klebsiella spp. Among Klebsiella spp. strains isolated from uncomplicated UTIs, those with low susceptibilities to almost cephems have increased in the latest period. To other antimicrobial agents, the susceptibilities of Klebsiella spp. did not show any changes during the latest period. 5. P. aeruginosa The susceptibilities to most agents of P. aeruginosa did not show any changes, the decreased susceptibilities to cefozopran (CZOP), carbapenems and monobactams of P. aeruginosa observed in 1996 appeared to have been retrieved in 1997. These susceptibility changes should be utilized in determining clinical treatments.

Anti-Bacterial Agents↗
PubMed1999

Evaluation of tibial component fixation in specimens retrieved at autopsy.

Fixation of the tibial component was evaluated in eight knees retrieved at autopsy by comparing their radiographs with measurements of micromovement between the component and the tibial plateau. Micromovement in the one cemented Miller-Galante and seven cementless Ortholoc components, which had been implanted for a range of 3 days to 57 months, was measured with linearly variable differential transducers under anteroposterior shear and axial compressive loads. Micromovement between the tibial component and the screws and between the tibial component and the bone after the screws were removed also was measured in the cementless specimens. Minimal micromovement in most of the implants suggests that the tibial components were well fixed. Micromovement between the tibial tray and the screws also was minimal in the cementless components. Removing the screws did not significantly affect micromovement, except in the specimen retrieved 3 days after surgery and in the specimen with a complete radiolucent line under the component. The cementless tibial components fixed with screws, pegs, and stem were as stable as the component secured with cement. Partial radiolucencies were not associated with greater micromotion than that of bone ingrown areas, but the component with complete radiolucency did have greater micromotion than that of all of the other specimens.

Biomechanical Phenomena↗
PubMed1999

[Regulation of the microtubule-dependent process formation. A review based on a comparison between the neuron and the renal glomerular podocyte].

Microtubular cytoskeletons play a crucial role in the morphogenesis of process-bearing cells, such as the neuron and the renal glomerular podocyte. Microtubules are bundled and stabilized by various microtubule-associated proteins, providing a mechanical basis to maintain the deviated morphology of cell processes. To support the process morphology, microtubules are also associated with other cytoskeletal elements such as actin and intermediate filaments. The microtubular polarity is uniformly plus-end-distal in neuronal axons, whereas in dendrites as well as in podocytes, the polarity is revealed to be non-uniform (i.e., both plus-end-distal and minus-end-distal microtubules are present in cell processes). Recently, this non-uniformity is reported to be established by a microtubule-dependent motor protein. Motor proteins are capable to drive the intracellular transport of cytoskeletal elements in addition to that of membrane vesicles. It is still an open question whether cytoskeletal elements are transported along cell processes as subunits or as polymers.

Animals↗
PubMed1999

Posterior tibial slope in the normal and varus knee.

Posterior tibial slope was evaluated in 30 normal and 30 varus knees using magnetic resonance imaging. The mean tibial posterior slope in the medial plateau was 10.7 degrees (range: 5 degrees - 15.5 degrees) in the normal knees and 9.9 degrees (range: 1.5 degrees - 19 degrees) in the varus knees. The mean tibial posterior slope in the lateral plateau was 7.2 degrees (range: 0 degrees - 14.5 degrees) in the normal knees and 6 degrees (range: 1 degrees - 13 degrees) in the varus knees. Although these differences were not statistically significant, there was a large range in the posterior tibial slope in both groups. When 10-mm thickness of bone was resected in the middle of the lateral plateau in total knee arthroplasty, the thickness of the bone resection in the anterior and posterior part of the lateral plateau was measured. The presumed thickness of bone was 10.1 mm (range: 7.3-13.9 mm) in the anterior part and 7.5 mm (range: 5-10.3 mm) in the posterior part. A large range in the measured thickness of bone also was detected in the varus knees. These results suggest that the shape of the proximal tibia varies among individuals and that the cutting angle should be determined in each case to avoid any mismatch of the patient's posterior slope of the tibia after implantation.

Case-Control Studies↗