Search PubMed⌕ Search

Biomedical subjects

T Kawase

Publications and source records attributed to T Kawase.

At least 37 records · Page 2Linked to original sources

Selection of surgical methods for infected infrarenal abdominal aortic aneurysms.

BACKGROUND: There is no standard treatment for patients with infected abdominal aortic aneurysm (AAA). To determine the basis for selection of a surgical method, we reviewed our experiences with all patients who underwent surgery for infected infrarenal AAA. METHODS: Between 1993 and 2000, 6 patients with infected infrarenal AAA underwent surgery. Extra-anatomic bypass grafting was performed in 2 of 3 patients with infection extending into the retroperitoneum. In situ grafting was performed in 3 patients with localized infection and in 1 patient with extended infection. RESULTS: Severe peritonitis occurred in 2 patients with extended infection in the early postoperative phase. One patient, who had undergone in situ grafting, died of sepsis. The other patient, who had undergone extra-anatomic bypass grafting, was treated by continuous irrigation with an electrolyzed strong acid aqueous solution (ESAAS). He recovered gradually and was discharged. After a follow-up period with a mean of 40 months (range: 17-102 months), all 5 patients who survived surgery are alive and asymptomatic. CONCLUSIONS: It was suggested that the method used for revascularization should be selected based on the degree of diffusion of infection. For a patient with extended infection, postoperative continuous irrigation with ESAAS appears to be effective in eradicating retroperitoneal infection.

Aged↗

High-performance liquid chromatographic method to analyze picomole levels of glutathione, cysteine and cysteinylglycine and its application to pre-cancerous rat livers.

A HPLC-based method for quantifying glutathione, cysteine and cysteine-containing peptide is described. N-(2,4-Dinitrophenylaminoethyl)maleimide was synthesized from ethylenediamine, 2,4-dinitrochlorobenzene and maleic anhydride. The maleimide was reacted at 40 degrees C and pH 5.8 for 10 min with thiol compounds such as glutathione or cysteine. An aliquot of the reaction mixtures was applied to a reversed-phase column (4.6 x 150 mm) of HPLC. When glutathione and cysteine were simultaneously assayed, the column was eluted with a gradient of acetonitrile in potassium phosphate (pH 7.0). The derivatives were monitored at 350 nm. Good liner relationships existed between peak area and concentration of glutathione or cysteine from 10 pmol to 2 nmol. The recovery tests from rat liver homogenate were 99.7+/-2.2% for glutathione and 104.9+/-3.8% for cysteine. By this method gamma-glutamylcysteine, cysteinylglycine, and homocysteine could be also quantified. The determination limits of glutathione, cysteine and other thiol compounds were 5 pmol. The method is simple: a sample solution is mixed with the labelling reagent and an aliquot of the reaction mixture is applied to a standard HPLC. The hepatic levels of cysteine and glutathione in pre-cancerous rats were determined by this method. The cysteine level in pre-cancerous livers was extremely elevated in comparison to that of the control groups, while no difference was observed in the glutathione contents between the pre-cancerous and control groups.

Animals↗

Expression of the neural RNA-binding protein Musashi1 in human gliomas.

Tumor cells arising from a particular tissue may exhibit the same gene expression patterns as their precursor cells. To test this proposition, we have analyzed the expression of a neural RNA-binding protein, Musashi1, in primary human central nervous system (CNS) tumors. In rodents, Musashi1 is expressed predominantly in proliferating multipotent neural precursor cells, but not in newly generated postmitotic neurons. The expression of Musashi1 is downregulated with the successive progression of neurogenesis. In normal adult human tissues, we detected low levels of Musashi1 expression in brain and testis by RT-PCR analysis. In an RNA panel of 32 cancer tissues and cell lines, elevated expression of Musashi1 was seen in all five malignant gliomas studied, in contrast to the slight expression seen in other tumor cells, including those in several melanomas and a prostate cancer. Western blot analysis showed strong Musashi1 expression in malignant gliomas compared with nonneoplastic brain tissue. Glioblastomas, the most malignant form of glioma, showed higher Musashi1 expression than less malignant gliomas by immunohistochemical analysis. Tumors with strong Musashi1 expression tended to have high proliferative activity. Thus, the expression of Musashi1 correlated with the grade of the malignancy and proliferative activity in gliomas. These results suggest that primary CNS tumors may share gene expression patterns with primitive, undifferentiated CNS cells and that Musashi1 may be a useful marker for the diagnosis of CNS tumors.

Adult↗

Survival and sinus rhythm maintenance after modified Cox/maze procedure and mitral valve operation in patients with chronic atrial fibrillation.

OBJECTIVE: Sinus rhythm gained after the Cox/maze procedure concomitant with mitral valve operation has demonstrated long-term attrition during the follow-up, no information exists on whether the type of mitral valve operation--(repair vs. replacement)--affects this sinus rhythm maintenance rate. We retrospectively studied patients undergoing concomitant mitral valve operation and Cox/maze procedure to answer this question. METHODS: Between April 1993 and August 1995, 87 consecutive patients--35 men and 52 women (mean age: 59.3 years)--with chronic atrial fibrillation and mitral valve disease underwent the modified Cox/maze procedure and concomitant mitral valve operation, with 56 having mitral valve repair (repair group) and 31 mitral valve replacement (replacement group). Patients were followed up and changes in rhythm studied retrospectively. RESULTS: Follow-up for a mean 51.3 +/- 11.6 months was completed in 82 of 83 long-term survivors (99%). Repair group surgery survival was 98.1 +/- 1.9% at 1 year and 94.2 +/- 3.2% at 5 based on the Kaplan-Meier method. Replacement group surgery survival was 85.7 +/- 5.9% at 1 year and 82.9 +/- 6.4% at 5. Probability in sinus rhythm maintenance for the repair group at 1 year was 88.6 +/- 5.4% and at 5 years was 67.6 +/- 9.1%. Probability in sinus rhythm maintenance for the replacement group at 1 year was 95.7 +/- 4.3% and at 5 years was 65.0 +/- 11.1%. CONCLUSIONS: Medium-term results after the Cox/maze III procedure concomitant with mitral valve operation are good. The attrition of sinus rhythm maintenance appears similar by the completion of 5-year follow-up.

Atrial Fibrillation↗

Aortic valve repair in dominant aortic regurgitation.

OBJECTIVE: We studied immediate and mid-term results after aortic valve repair. METHODS: Immediate and mid-term results were studied in 63 patients undergoing aortic valve repair, calculating survival and reoperation free rates. RESULTS: Subjects were 49 men and 14 women aged 15 to 76 years (mean: 53 +/- 17 years). Mean preoperative aortic regurgitation grading of 1 to 4 was 3.2 +/- 0.7. Mean preoperative New York Heart Association functional class was 1.9 +/- 0.8. Two in-hospital deaths occurred. (3.2%) Mean aortic regurgitation grade at discharge was 1.3 +/- 0.8 (p < 0.0001; vs preoperative grade) and functional class was 1.1 +/- 0.2 (p < 0.0001; vs preoperative class),--significantly improved. Overall follow-up was 98.4%, and mean follow-up continued 41.4 +/- 22.1 months. Mean functional class at follow-up was 1.2 +/- 0.4 (n = 49), improved from preoperative class (p < 0.0001). Mean aortic regurgitation grading at follow-up was 1.8 +/- 0.8 (n = 41), improved from preoperative grading (p < 0.0001). Five-year survival was 95.1 +/- 2.8%. One-year reoperation freedom was 96.6 +/- 2.4% and 5-year 77.9 +/- 6.9%. CONCLUSIONS: Survival after surgery was good, while reoperation was comparable to other reports but less satisfactory compared to reoperation freedom after aortic valve replacement. Based on reoperative findings, a change in indication was made. We believe technical refinements could improve postoperative results.

Adolescent↗

A giant internal carotid-posterior communicating artery aneurysm presenting with atypical trigeminal neuralgia and facial nerve palsy in a patient with autosomal dominant polycystic kidney disease: a case report.

BACKGROUND: In cases of internal carotid-posterior communicating artery (IC-PC) aneurysm, involvement of the trigeminal nerve at its root is rare, and facial nerve palsy is even more unusual. CASE REPORT: A large, unruptured IC-PC aneurysm was detected in a 56-year-old man with autosomal dominant polycystic kidney disease (ADPKD), but surgery was not performed because of mild renal dysfunction. Two months later, a sudden, severe headache suggested a subarachnoid hemorrhage, which was ruled out by computed tomography and lumbar puncture. Neurological examination revealed complete oculomotor palsy, atypical trigeminal neuralgia, and facial palsy with gustatory disturbance. Magnetic resonance (MR) imaging revealed a partially thrombosed giant aneurysm that directly compressed the trigeminal nerve root, reached the internal auditory canal, and was adjacent to the facial nerve. The neck of the aneurysm was successfully clipped via a subtemporal transtentorial approach. The postoperative course was uneventful, and all neurological symptoms had resolved within 3 months. CONCLUSIONS: We believe that the prosopalgia in this case was atypical trigeminal neuralgia due to direct compression of the trigeminal nerve root by the aneurysmal sac. A contributory cause was stretching of the oculomotor nerve, which contains sensory afferent inhibitory fibers derived from the ophthalmic branch of the trigeminal nerve. The facial palsy was of peripheral type and was accompanied by gustatory disturbance. This is the first reported case of facial palsy caused by an IC-PC aneurysm and also a very rare case of an IC-PC aneurysm clipped by a subtemporal transtentorial approach.

Carotid Artery Diseases↗

Survival of a subarachnoid hemorrhage patient who presented with prehospital cardiopulmonary arrest: case report and review of the literature.

A 63-year-old woman was admitted to the intensive care unit after resuscitation from prehospital cardiopulmonary arrest (CPA). A brain CT scan revealed a subarachnoid hemorrhage (SAH), which was considered to be the cause of the CPA. The patient recovered neurologically after admission, and the elevated intracranial pressure (ICP) was controlled by inducing mild hypothermia. The day after admission, cerebral angiography revealed a ruptured cerebral aneurysm. The aneurysm was successfully treated with detachable coils by an endovascular technique. Mild hypothermia was continued for 3 days, and the patient was gradually rewarmed. After rehabilitation, the patient was discharged to her home with severe disability. Although aneurysmal SAH is one of the most common causes of CPA, survival of SAH patients after CPA is rare. This case illustrates the ability and possibility of multidisciplinary treatment, including the use of endovascular techniques and mild hypothermia, to improve the outcome of SAH patients with CPA who have been considered to be inoperable and untreatable.

Cardiopulmonary Resuscitation↗

Measurement of stapes mobility in guinea pigs and rabbits.

In tympanoplasty, it is essential to know the condition of the stapes. However, it has been difficult to evaluate stapes mobility in routine measurement. With the eye on improving future clinical practice, in this study we developed a new, easy system of measuring stapes mobility quantitatively and, as a first step, applied it to measurement of the relationship between the load and displacement of the stapes in guinea pigs and rabbits. The stapes displacement increased linearly with an increase in load in the small displacement region, and increased nonlinearly in the large displacement region. The slope of the regression line of this stiffness curve in the small displacement region was used as an index of the stapes mobility. The values in the guinea pigs and rabbits were 16+/-7 N/m and 115+/-25 N/m, respectively. A significant difference between the two species was observed.

Animals↗

Evidence for involvement of dysfunctional teeth in the senile process in the hippocampus of SAMP8 mice.

In order to evaluate the involvement of dysfunctional teeth in age-related deficits in hippocampal function, we examined the effect of removal of molar teeth (molarless condition) on neuronal degeneration and glial fibrous acidic protein (GFAP) expression in the hippocampus and on learning ability in a water maze test in young, middle-aged, and aged accelerated senescence-prone mice (SAMP8). The molarless condition enhanced an age-dependent decrease in both learning ability and the number of neurons in the hippocampal CA1 subfield and the age-dependent increase in the number and hypertrophy of GFAP-labeled astrocytes in the same subfield. These observations suggest that the molarless condition may be involved in the senile process in the hippocampus in SAMP8 mice.

Aging, Premature↗

Expression of cementum-derived attachment protein in bovine tooth germ during cementogenesis.

Cementum-derived attachment protein (CAP) is a 56 kDa collagenous protein that promotes attachment of mesenchymal cells. Previous studies have shown that the presence of CAP is restricted to cementum in adult human tissues. In this study, we report generation of a monoclonal antibody against CAP and its use for the investigation of CAP in developing bovine tooth germs. Mice were immunized with CAP purified from bovine cementum, and a monoclonal antibody, 3G9, was produced. Immunohistochemical staining of bovine tooth germ at root forming stage using 3G9 antibody showed that the tissue distribution of CAP expression was limited to cementum matrix and cementoblasts during cementogenesis. Alveolar bone did not stain with the 3G9 antibody, whereas anti-type I collagen stained positively. CAP was purified from bovine tooth germs with immunoaffinity purification using the 3G9 antibody. Examination of the immunoaffinity-purified fraction showed that CAP existed in tooth germ as a 65 kDa protein. The protein was susceptible to bacterial collagenase. To investigate the possible biological function of CAP during cementogenesis, we isolated dental follicle cells from the bovine tooth germ, and showed that they adhered to surfaces containing CAP. These data demonstrate that CAP is expressed by bovine cementoblasts as a 65 kDa protein and that the CAP may have a function in cementogenesis.

Animals↗

Enamel matrix derivative (EMDOGAIN) rapidly stimulates phosphorylation of the MAP kinase family and nuclear accumulation of smad2 in both oral epithelial and fibroblastic human cells.

In our previous study, we demonstrated that porcine enamel matrix derivative (EMD) induces p21WAF1/cip1 within 8 hours and subsequently arrests the cell cycle of human oral epithelial cells in G1 phase. In contrast, EMD markedly stimulates the proliferation of gingival fibroblasts without inducing p21WAF1/cip1. To investigate the mechanism of how EMD produces these differential effects, we have focused on the initial response of these two cell types to EMD. In epithelial cell cultures, EMD stimulated cytoskeletal actin polymerization within 30 min and promoted cell adhesion in our experimental system. EMD failed to stimulate either intracellular Ca2+ mobilization or cAMP production in either cell type. In both epithelial and fibroblastic cells, EMD (25-100 microgram/ml) rapidly produced dose-dependent phosphorylation of the mitogen-activated protein kinase (MAPK) family: extracellular signal response kinase (ERK), p38-MAPK (p38-K), and c-Jun-terminal kinase/stress-activated protein kinase (JNK). However, neither inhibitors of MEK (ERK kinase) nor p38-K could block EMD's anti-proliferative action on epithelial cells. On the other hand, EMD rapidly stimulated translocation of smad2 into the nucleus in both cell types. Spurred by this finding, we assayed for TGF-beta1, a ligand for one receptor associated with smad2 activation, and detected significant levels in EMD preparations. The sum of these pharmacological findings indicates that EMD contains at least one bioactive factor, which is most probably TGF-beta1 (or TGF-beta-like substances). In conjunction with the similarities in the differential growth-modulating actions between EMD and what is known for TGF-beta, we suggest that TGF-beta might act as the principal growth regulating agent of oral fibroblastic and epithelial cell types in EMD despite being present in only low levels.

Actins↗

Hemodialysis paradox: survey on the incidence rate of hepatocellular carcinoma in antihepatitis virus C-antibody-positive chronic hemodialysis patients.

The prevalence of antihepatitis virus C (HCV) antibodies in chronic hemodialysis (HD) patients is higher than in normal populations, and yet hepatocellular carcinoma (HCC) is infrequent in chronic HD patients who are HCV antibody positive. In this study, we investigated the characteristics of HCV-antibody-positive patients with HCC on chronic HD. A total of 6,366 cases of HCV-antibody-positive patients on chronic HD therapy was analyzed on the basis of answers to questionnaires on the incidence rate of HCC in 314 Japanese dialysis institutions. HCC was a complication in 114 of 6,222 (1.8%) HCV-antibody-positive patients, and cirrhosis was a complication in 536 of 6,242 (8.6%). The incidence rate of both complications was significantly higher in males than in females, and the incidence rate in the chronic HD patients was much lower than in normal populations. Specific immunological status in patients on chronic HD therapy may be an important key for preventing the progression of chronic HCV hepatitis. However, further research is needed because this study was preliminary and excluded the type of HCV virus, pathological findings, and laboratory data.

Carcinoma, Hepatocellular↗

The expression of apoptosis-related proteins in the aged cochlea of Mongolian gerbils.

OBJECTIVE: Apoptotic changes have been reported in the aged gerbil cochlea and are speculated to be one of the principal causes of presbyacusis. The objective of the study was to determine the underlying mechanism of apoptotic change in the aged gerbil cochlea. STUDY DESIGN: Prospective controlled animal study. METHODS: We examined the tissue distribution of bcl-2, bax, caspase-3p20, and caspase-3p32 using immunohistochemical techniques in the young and aged gerbil cochlea, together with the measurement of the distortion product of otoacoustic emission (DPOAE). RESULTS: Aged gerbils showed a significant reduction of the DPOAE amplitude as compared with that of the young gerbils, suggesting a disturbance of the auditory function in the aged cochlea. There was a significant decrease in the number of bcl-2-positive cells in the aged gerbils. The expression of bax in the aged group was slightly increased but did not significantly differ from that in the young gerbils. A significantly increased number of caspase-3p20-positive cells was observed in the organ of Corti, spiral ganglion, and lateral wall of cochlea in the aged gerbils as compared with those of the young gerbils. There was no significant difference in the expression levels of caspase-3p32 between the young and aged groups. In the aged cochlea, the degree of deterioration of DPOAE responses was compatible with those of both the reduction of bcl-2 and the activation of caspase-3p20. CONCLUSION: These data suggest that the suppression of bcl-2 protein expression may lead to apoptosis-induced presbyacusis through activation of caspase-3 in the aged gerbil cochlea.

Age Factors↗

Intra-ischemic hypothermia attenuates intercellular adhesion molecule-1 (ICAM-1) and migration of neutrophil.

Adhesion of neutrophil to the endothelium and subsequent transmigration has been reported to contribute to progression of focal ischemia. Hypothermia has been known to attenuate ischemic insult through various mechanisms of action. The authors evaluated the effect of hypothermia on expression of intercellular adhesion molecule-1 (ICAM-1) protein and on transmigration of neutrophil with immunohistochemical method. Transient focal ischemia model in rats was employed, and animals received 2 h of either normothermic or hypothermic ischemia. To confirm the effectiveness of hypothermia on neuroprotection, cortical infarct area was compared between the two groups. Our results demonstrated that hypothermia reduced both the number of microvessels expressing ICAM-1 and that of neutrophils migrating into ischemic tissue. Comparison of cortical infarct area showed persistent protective effect. This study indicates that reduction of ICAM-1 expression and subsequent reduction of migrating neutrophil in hypothermia can contribute to attenuation of ischemic damage.

Animals↗

Removal of anterior clinoid process for basilar tip aneurysm: clinical and cadaveric analysis.

The difficulty in the operation for basilar tip aneurysm is the restriction in surgical working space. To resolve this problem, aggressive skull base surgery has been reported, but these techniques are not prevalent. Pterional and subtemporal approaches are commonly used for basilar tip aneurysms. In an attempt to increase the surgical working space during the pterional approach, the anterior clinoid process and the roof of the optic nerve were removed extradurally to increase the mobilization of the intracranial internal carotid artery and optic nerve. The effects of removing the anterior clinoid process and microanatomy in the perioptic area were analyzed by cadaveric procedures in 10 cases (20 sides). With this procedure, the internal carotid artery can be retracted medially with a spatula 6.1 +/- 0.8 mm (mean +/- SD). The length and the area of dural fold in the bone defect region in the optic canal roof are 2.1 mm and 13.6 mm. In 10 clinical cases, this procedure allowed enough space to approach the basilar tip aneurysm without disturbing the internal carotid artery blood flow. The clinical outcome was satisfactory.

Basilar Artery↗

Cerebral microaneurysms found incidentally during aneurysm surgery.

Not uncommonly, cerebral microaneurysms are found incidentally during surgery for another previously diagnosed cerebral aneurysm(s). The frequency and angiographic characteristics of such incidental microaneurysms are retrospectively summarized. Seventeen patients were identified as harboring incidental microaneurysms, comprising 4.9% of the whole series. The middle cerebral artery (MCA) was the most frequent location (seven cases, 41%) of these microaneurysms. There was a tendency for MCA microaneurysms to be contiguous to a previously known, larger aneurysm at the same location. Neurosurgeons as well as interventional neuroradiologists should be aware of the possible presence of these incidental microaneurysms while treating patients with a cerebral aneurysm(s). Although the actual clinical implications of these incidental microaneurysms have not been elucidated, the few additional risks to patients already surgically exposed for the treatment of another aneurysm, along with the possible benefit of preventing their rupture and growth, would justify the surgical treatment of these microaneurysms.

Adult↗

Method to improve cosmetic outcome following craniotomy.

This technical note describes a simple method for reducing the dead space created by craniotome due to the loss of bone dust and improving the cosmetic outcome following a craniotomy. After drilling the burr holes for the craniotomy, the bone between the holes is drilled away in a standard fashion except that multiple regions of about 1 cm in length are left intact. These intact regions are broken using a periosteal elevator and fixed like a bridge when the bone is replaced. The resulting bone flap is readily returned to its original position without making the dead space created by regular craniotomy. The amount of the dead space caused by losing the bone dust is reduced and a good cosmetic recovery is obtained. This technique is useful for both craniotomy and facial bone surgery, which requires cosmetic results.

Bone and Bones↗