Biomedical subjects

H Matsuda

Publications and source records attributed to H Matsuda.

At least 685 records · Page 38Linked to original sources

PubMed1997

Consecutive maintenance of human solitary and hereditary colorectal polyps in SCID mice.

Recently, the sequential changes from adenoma to adenocarcinoma have been well studied in human colorectal carcinogenesis. To study the precise clonal changes from colorectal polyps to cancer, we have established an experimental system to maintain human colorectal polyps in severe combined immunodeficient (SCID) mice that have been improved by the selective inbreeding of C.B17-scid/scid homozygous male and female showing undetectable serum IgG and IgM (< 1 microgram/ml). Two of two solitary polyps from two nonhereditary colon polyp patients, four of five colon polyps from two Peutz-Jeghers' syndrome patients and one polypoid lesion from a familial polyposis coli (FAP) patient grew very slowly but steadily, at approximately one-tenth the rate of their malignant form, (i.e., adenocarcinoma), in the improved SCID mice and were maintained for a long period (more than 2 years), over several mouse generations. However, two polyps from FAP and Peutz-Jeghers' syndrome patients could not be transplanted further because of microinfection at the transplanted site due to incomplete sterilization of original human tumors prior to surgical operation (endoscopic polypectomy). Transplanted colon polyps had a semitransparent, soft and sticky appearance, with cells containing large amounts of mucin. Malignant transformation of human colon polyp to adenocarcinoma has not been observed during the maintenance period (about 2 years) in SCID mice. In the consecutively maintained human colon polyps, however, K-ras mutations were detected at codon 12, while these mutations were not found in their original polyps in the patients.

Adenomatous Polyposis Coli↗

PubMed1997

Genetic variations in human benign prostatic hyperplasia detected by restriction landmark genomic scanning.

Alterations in the genomic DNAs of benign prostatic hyperplasias were examined using restriction landmark genomic scanning. This methodology allows the visual comparison of a large number of loci as spots within a gel that has been electrophoresed in 2 dimensions. Within each of the 16 hyperplasias examined, we found 2 to 10 spots with altered intensities, as compared to equivalent spots from normal prostate, but could detect few common spot profiles for any hyperplasia samples. These data conflict with data from previous studies and suggest that there may be no consistent genetic changes in the pathogenesis of some forms of human benign prostatic hyperplasia.

Aged↗

PubMed1997

[A patient with epilepsy manifesting reversible memory dysfunction--a neuropsychological, electroencephalographical and radiological study].

A 49-year-old man was admitted to our hospital because of epileptic seizures and memory dysfunction. He had been experiencing seizures several times a day since the age of 43 years. Despite antiepileptic drug therapy (sodium valproate [VPA] and clonazepam [CZP], he suffered from frequent complex partial seizures originating in the temporal lobe, and he had a memory disturbance since age 47. When carbamazepine (CBZ) was substituted for VPA and CZP, the epileptic seizures stopped and the memory disturbance improved. Noninvasive regional cerebral blood flow (rCBF) measurements using 99mTc-HMPAO-SPECT imaging were performed twice. The initial measurements on admission showed overall decreased rCBP that was more prominent in the cerebral cortex than in the subcortical nuclei. A follow-up SPECT examination after clinical improvement revealed a marked overall increase in rCBF, especially in the cerebral cortex. The SPECT findings suggest that the memory disturbance in this patient may have been associated with the overall cerebral blood hypoperfusion. This overall hypoperfusion can be attributed to the frequent complex partial seizures and/or the adverse effect of VPA and CZP. SPECT can provide important information suggesting the pathogenesis of memory disturbance associated with epilepsy.

Anticonvulsants↗

PubMed1997

Reduction of progressive burn injury by using a new nonselective endothelin-A and endothelin-B receptor antagonist, TAK-044: an experimental study in rats.

Endothelins are well-known vasoconstrictor peptides produced by vascular endothelial cells that have been reported to have a fundamental role in regulation of the systemic blood circulation. Plasma levels of endothelins are increased by burn injury, which also causes thrombosis and occlusion of vessels in the dermis as well as a vascular response in the adjacent uninjured dermis. Diminished blood flow leads to progressive ischemia and necrosis of the dermis beneath and around the burn (zone of stasis). If blood flow could be restored in this zone, secondary tissue damage would be minimized. In this study we examined the effects of a new nonselective endothelin receptor antagonist, TAK-044 (Takeda Chemical Industries, Ltd., Osaka, Japan), on burn trauma in rats. Fifty male Sprague-Dawley rats weighing an average of 450 gm were burned with a brass probe that produced a row of three burns 10 x 30 mm in size and two intervening unburned areas 5 x 30 mm in size. Rats were divided into five groups of 10 animals. Four groups received 0.01, 0.1, 1 or 10 mg/kg of TAK-044 via the dorsal vein of the penis immediately after burn trauma, while the control group received the same volume of saline. Skin blood flow was measured with a laser-Doppler flowmeter, and the development of edema and the area of necrotic tissue also were determined. Inhibition of endothelin activity by TAK-044 after burn injury improved microvascular perfusion in the zone of stasis and prevented the progression of tissue damage in this zone. This supports the role of endothelins in the progression of burn injury in the zone of stasis. TAK-044 was most effective in preventing progressive burn damage at a dose of 1 mg/kg. The extent of necrosis and edema was reduced significantly, and blood flow in the zone of stasis was increased in the treated rats.

Animals↗

PubMed1997

[David's operation for aortic regurgitation associated with annulo-aortic ectasia].

A 54-year-old man with AR due to AAE underwent the replacement of ascending aorta by sparing an aortic valve (David operation). Under cardiopulmonary bypass, the aneurysmal aorta and the all three sinuses of valsalva were excised, leaving 5 mm of arterial wall attached to the aortic valve. The aortic valve was reimplanted inside a Dacron graft (28 mm Hemashield) which was calculated by aortic valve leaflet height as well as from the size of LVOT. The patient has survived the operative procedure and showed uneventful recovery. We believe this new procedure preserving the native aortic valve is useful for preventing from some complications associated with an artificial heart valve and improvement of QOL of patient.

Aorta↗

PubMed1997

Laparoscopic cholecystectomy in patients with cardiac disease: hemodynamic advantage of the abdominal wall retraction method.

We examined the use of an abdominal wall retraction method instead of pneumoperitoneum in laparoscopic cholecystectomy for patients with cardiac disease to prevent the hemodynamic deterioration associated with pneumoperitoneum. Eight patients with cardiac diseases, mainly valvular or coronary artery diseases, underwent laparoscopic cholecystectomy under hemodynamic monitoring. Five patients without cardiac disease served as controls. As hemodynamic parameters, heart rate, mean systemic arterial pressure (mAP), mean pulmonary arterial pressure (mPAP), central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), and cardiac index (CI) were measured. The patients with cardiac disease showed significantly elevated mPAP and PCWP compared with the control group under pneumoperitoneum, and one patient showed critically decreased CI due to increased tricuspid regurgitation under pneumoperitoneum. These changes, however, were resolved on the abdominal wall retraction. There was no major perioperative complication. This abdominal wall retraction method is, therefore, favorable for patients with underlying cardiac disease to minimize the hemodynamic deterioration during laparoscopic cholecystectomy.

Abdominal Muscles↗

PubMed1997

Bcl-2 and Bcl-xL block apoptosis as well as necrosis: possible involvement of common mediators in apoptotic and necrotic signal transduction pathways.

The proto-oncogene bcl-2 and a bcl-2-related gene bcl-x prevent apoptotic cell death induced by various treatments. Although a mechanism has been proposed that involves Bcl-2 activity on reactive oxygen species (ROS), we find that expression of Bcl-2 or Bcl-xL prevents cell death induced by withdrawal of oxygen (hypoxia) and that the cell death does not involve ROS, suggesting that Bcl-2 or Bcl-xL exerts an anti-cell death function by a mechanism other than through regulation of ROS activity. Using electron microscopy, and confocal and non-confocal fluorescence microscopy, we show that hypoxia induces both necrosis and apoptosis. Overexpression of Bcl-2 or Bcl-xL blocks hypoxia-induced apoptosis and, although to a lesser extent, necrosis. The anti-apoptotic proteins Bcl-2 and Bcl-xL effectively inhibit KCN-induced cell death which is characterized by necrotic features including apparently intact chromatin, remarkable mitochondrial swelling with loss of crista structure and loss of plasma membrane integrity. The necrotic cell death is also inhibited by inhibitors of ICE (interleukin-1 beta converting enzyme)(-like) proteases, the common mediators of apoptosis. These results indicate that Bcl-2/Bcl-xL and ICE(-like) proteases modulate both apoptotic and at least some forms of necrotic cell death, suggesting that both cell death pathways involve some common mediators.

Animals↗

PubMed1997

Expression of macrophage migration inhibitory factor in corneal wound healing in rats.

PURPOSE: The study was conducted to evaluate the expression of macrophage migration inhibitory factor (MIF) during penetrating corneal injury. METHOD: A penetrating linear incision (2 mm) was made in the center of the right cornea with a razor blade. The expression of MIF in the lacerated eye and in the contralateral eye was examined by immunohistochemistry at 3, 6, 24, 48, and 72 hours after injury. Concentrations of MIF in the aqueous humor of the injured and contralateral eyes were also measured by enzyme-linked immunosorbent assay. The expression of MIF messenger RNA (mRNA) in the injured cornea was quantified by reverse transcription-polymerase chain reaction and subsequent Southern blot analysis. RESULTS: Positive migration inhibitory factor staining was observed in the basal cells of epithelial and endothelial cells of the normal rat cornea. The positive staining of the central corneal epithelium diminished at 3 hours after injury. At 6 hours after injury, positive MIF staining reappeared on the basal cells of the injured area, whereas the staining of the contralateral eye remained unchanged. Enzyme-linked immunosorbent assay of the aqueous humor revealed that the MIF concentration was elevated in both the injured and the contralateral eyes. The maximum concentration of aqueous MIF was observed at 6 hours after injury in both eyes. Reverse transcription-polymerase chain reaction and Southern blot analysis revealed that MIF-mRNA expression in the injured cornea increased from 6 to 48 hours after injury. CONCLUSION: The results of immunohistochemistry suggest the possibility that MIF is released from the corneal epithelial cells of the injured eye within 3 hours. Conversely, the MIF-mRNA level of the injured cornea is increased from 6 to 48 hours after injury and then diminished. In addition, unilateral corneal injury induces bilateral upregulation of MIF in the aqueous humor.

Animals↗

PubMed1997

[Cardiovascular surgery in the patients with liver dysfunction].

Under the current situations we have increasing opportunities to manage the patients with posthepatitis and/or congestive liver dysfunction. In order to prevent postoperative hepatic failure we described perioperative management for those patients. For this purpose, the major point is the selection of appropriate operative methods which reduce operative invasions and have sure efficacy. In order to decide operative methods, we have to grasp the functional reserve of dysfunctional liver. We have no effective methods to estimate the functional reserve, but our data suggested that serum cholinesterase level at the preoperative states might demonstrate prognostic significance. The others are managements of postoperative cardiopulmonary distress and infection. It goes without saying that preoperative improvement of anemia and poor nutrition.

Adolescent↗

PubMed1997

Proton nuclear magnetic resonance detects leucine, 2,3-butanediol, and a prominent increase in the level of choline in the sera from patients chronically infected with schistosomiasis japonica.

1H-NMR spectroscopy with 'Hahn' spin-echo pulse sequence has been employed to investigate the metabolic profiles of sera of chronic patients with schistosomiasis japonica, and compared with those of healthy volunteers and former patients who had been treated successfully. 1H-NMR clearly detected 2,3-butanediol and leucine, and markedly elevated levels of choline in sera from the chronic patients. Profiles of the sera from former patients were essentially similar to those from healthy volunteers, except that ketone bodies (3-hydroxybutyrate and acetone) were detectable in sera from 58% of the former patients but not in those of the normal controls patients.

Adolescent↗

PubMed1997

Concomitant cardiac and pulmonary operation. Pulmonary mechanics and outcome of phrenic nerve injury.

OBJECTIVE: We describe the postoperative respiratory failure due to the phrenic nerve injury in the setting of concomitant cardiac and pulmonary operation. EXPERIMENTAL STUDY: Prospective study. SETTING: Department of Cardiac and Thoracic Surgery Osaka University Medical School. PATIENTS AND INTERVENTIONS: From January 1984 to December 1993, 5 patients (1.4%) underwent the concomitant cardiac and pulmonary operation out of 359 patients who received surgical treatment for lung cancer at our institution. MEASURES AND RESULTS: Three (60%) out of 5 patients required prolonged mechanical ventilation despite the absence of cardiac complication, lung edema or pneumonia. Diaphragm function and work of breathing were measured in two patients before and after weaning from mechanical ventilation. Phrenic nerve dysfunction was consistent with the result that trans-diaphragmatic pressure (delta Pdi) was low, a ratio of gastric to esophageal pressure swing (delta Pga/delta Pes) was abnormally negative, and work of breathing (WOB) was high. Phrenic nerve function restored associated with clinical improvement. CONCLUSIONS: Diaphragm dysfunction and an increase in work of breathing may be potential causes of respiratory failure in patients after concomitant cardiac and pulmonary operation. This compromise in respiratory mechanics should not be overlooked in the postoperative care, which may lead to the best management in postoperative respiratory care.

Aged↗

PubMed1997

Differential expression of maf-1 and maf-2 genes in the developing rat lens.

PURPOSE: To examine the expression of maf-1 and maf-2 protocogenes in the developing rat lens. METHODS: Maf-1 and maf-2 transcripts were assayed in rat lenses on embryonic days 13 and 16 (E13 and E16) by in situ hybridization using single-stranded RNA probes. Proteins encoded by the maf-2 gene were assayed immunocytochemically in embryonic (E12, 13, 16, 19) and postnatal day 14 and 90 (P14 and P90) lenses. RESULTS: In embryonic lenses, we detected maf-1 messenger RNA (mRNA) in the lens epithelium and maf-2 mRNA diffusely distributed in the lens fiber cells. By immunocytochemistry, Maf-2 was detected on E12 in the nuclei of almost all lens pit cells. On days E13, E16, and E19, however, lens epithelial cells showed no immunoreactivity, but nuclei of fiber cells reacted strongly. On P14, nuclei containing Maf-2 protein were confined to the equator of the lens, but at 3 months of age, no Maf-2 could be detected in the rat lens. Western blotting showed that the anti-Maf-2 antiserum reacted with a single protein, of molecular weight approximately 39 kDa, in rat lens. CONCLUSIONS: Results showed the spatial and temporal regulation of maf gene expression and suggest that these genes participate in transcriptional regulation during the development of the lens in the rat.

Animals↗

PubMed1997

An approach to detection of protein structural motifs using an encoding scheme of backbone conformations.

This paper presents an approach to detection of protein structural motifs. In our approach, first all protein backbone conformations are converted into character strings using an encoding scheme. Then we use the Smith-Waterman local alignment algorithm to detect common structural motifs. By comparing results with the PROSITE regular expression patterns, our method can detect several motifs which the PROSITE patterns fail to detect.

Amino Acid Sequence↗

PubMed1997

Role of angiotensin II generated by angiotensin converting enzyme-independent pathways in canine kidney.

Recent studies have provided evidence of angiotensin converting enzyme (ACE)-independent angiotensin (Ang) II formation in tissue renin-angiotensin systems. We studied the effects of Ang II generated by ACE-independent pathways on renal hemodynamics. We used a synthetic peptide, [Pro11, D-Ala12]-Ang I (S), which yields Ang II by chymase, but not by ACE. Infusion of Ang I into a renal artery caused a decrease in renal blood flow, and reciprocally an increase in mean arterial pressure. Infusion of S (1 nmol/kg) caused a decrease in renal blood flow (-20%), but a larger dose was needed to increase mean arterial pressure. Studies with an intravital needle-probe CCD camera revealed that the Ang I infusion induced dose-dependent vasoconstriction of afferent and efferent arterioles (49% and 54%, respectively at 1 nmol/kg). In contrast, infusion of S elicited only 30% constriction of these vessels at a dose of 1 nmol/kg and induced no further constriction at higher doses, indicating that different segments of renal vessels responded in different fashions to Ang II formed via ACE-independent pathways. These vasoconstrictions were abolished by an angiotensin II receptor (AT-1) antagonist. Enzymatic assays using reverse-phase HPLC revealed that the ACE-dependent pathway was predominant in the rena1 cortex (approximately 80%). We also determined Ang II concentrations in renal cortex specimens obtained by needle biopsy. Intrarenal S infusion (10 nmol/kg) increased plasma and renal Ang II concentrations to 160% and 710% of the respective baseline levels. This study provides in vivo evidence of ACE-independent Ang II formation in renal tissue and suggests that this locally-formed Ang II influences the renal circulation in a paracrine fashion.

Angiotensin II↗

PubMed1997

A case of bilateral optic neuropathy and recurrent transverse myelopathy associated with perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA).

A case involving a 52-year-old man having bilateral optic neuropathy and recurrent transverse myelopathy is reported. His clinical features resembled multiple sclerosis, but neuroimaging failed to show evidence of demyelination or inflammation in the brain or the optic nerves. The patient experienced sudden visual loss despite massive steroid therapy. Positive perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) is suggestive that optic neuropathy and recurrent transverse myelopathy may have been caused by some common inflammatory processes associated with p-ANCA, however, having a different etiology from multiple sclerosis.

Antibodies, Antineutrophil Cytoplasmic↗

PubMed1997

[Noninvasive hemodynamic assessment of internal thoracic artery grafts using duplex echocardiography from supraclavicular fossa--a comparison with Doppler catheter method].

We evaluated the usefulness of noninvasive hemodynamic assessment of internal thoracic artery grafts (ITAGs) using duplex Doppler echocardiography from the supraclavicular fossa (transcutaneous pulsed Doppler method: PD method). Eighteen ITAGs were examined by PD method in comparison with Doppler catheter method using Doppler flowire (DC method). The hemodynamic indices used were the diastolic/systolic peak velocity ratio (DSVR) and the diastolic fraction of time-velocity integral (DF) in the ITAGs. A significant linear correlation was seen both in DSVR and DF between these two methods (p < 0.01). The subjects were assigned to two groups according to angiographic findings Group A (Gr-A: 5 grafts) with string sign including significant graft stenosis and group B (Gr-B 13 grafts) with good patency. In both PD and DC methods, DSVR and DF were significantly lower in Gr-A than in Gr-B (p < 0.01). The blood flow pattern was thus systolic dominant in the grafts with string sign, while it was diastolic dominant in the grafts with good patency. In some grafts in Gr-B, however, both DSVR ad DF were as low as that in Gr-A. Responding to pacing, Gr-B further increased both DSVR and DF, but Gr-A did not. As a result, the difference between both groups was further distinguished. In summary, ITAG function can be assessed by the noninvasive PD method. Interventions such as exercise, dobutamine infusion may make it more accurate, particularly in evaluating borderline data.

Aged↗

PubMed1996

Functional properties of murine macrophages promoted by nerve growth factor.

The stimulating effect of nerve growth factor (NGF) on phagocytosis, parasite killing, and interleukin-1beta (IL-1beta) production of murine peritoneal macrophages was assessed. In the presence of various doses of NGF, macrophages showed the increased phagocytosis of both nonspecific hydrophilic microspheres and sheep red blood cells (SRBC) opsonized with anti-SRBC antibodies (Ab) or complement in a dose-dependent manner. NGF also enhanced killing of Leishmania donovani promastigotes by macrophages, and its ability was comparable with that of an optimal dose of recombinant granulocyte-macrophage colony-stimulating factor or recombinant interferon-gamma. The addition of NGF to peritoneal macrophages and monocyte-macrophage J774A.1 cells led to a significant release of IL-1beta in a dose-dependent manner and expression of IL-1beta mRNA. Because pretreatment of peritoneal macrophages and J774A.1 cells with K-252a, a tyrosine kinase inhibitor, completely suppressed these NGF-mediated stimulating effects and p140trk phosphorylation and because flow cytometric analysis with specific Ab against two distinct NGF receptors showed the expression of p140trk, unlike p75LNGFR, on the surface of macrophages, the stimulating activity of NGF to murine macrophages may be mediated through p140trk. Thus, NGF may act as an activator for murine macrophages in the process of inflammatory and immune actions.

3T3 Cells↗

PubMed1996

The responses of skin blood flow, mean arterial pressure and R-R interval induced by cold stimulation with cold wind and ice water.

This study was designed to evaluate the peripheral circulation response to cold wind stimulation. Skin blood flow (SBF), ECG R-R intervals (RRs) and mean arterial pressure (MAP) were measured in ten healthy men under strictly controlled conditions. Cold wind flow and ice water bath were prepared as cold stimulations. The subjects were exposed to each cold stimulation and the values of the responses were simultaneously recorded. The cold wind stimulation reduced SBF (maximally 40.4 +/- 3.2%) and increased MAP (maximally 106.9 +/- 1.3%), but did not affect RRs. On the other hand, all parameters were affected by the ice water stimulation, which reduced SBF to 16.4 +/- 1.2% and RRs to 85.1 +/- 3.0%, and increased MAP to 130.6 +/- 2.4% compared with the control state. All subjects suffered from intense pain during the ice water but not the cold wind stimulation, and two of them were eliminated from this study because of vagotonia. After phentolamine iontophoresis was used to block the receptor of peripheral alpha-adrenergic nerve terminals, the cold wind stimulation did not affect SBF. These results suggest that cold wind stimulation is a useful test for evaluating peripheral alpha-adrenergic nerve function in relation to cold sensation, without increase of RRs and noxious pain.

Adolescent↗