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Biomedical subjects

S Kawaguchi

Publications and source records attributed to S Kawaguchi.

At least 163 records · Page 9Linked to original sources
PubMed1994

Lateral approach for anterior thoracic spinal lesions.

A lateral approach, consisting of a modified transversectomy, hemilaminectomy, and adequate transversectomy with costectomy of 7-8 cm, was used to treat four cases of anterior or anterolateral thoracic lesions, including two cases of thoracic disc herniations, one of thoracic meningioma, and one of hypertrophic pachymeningitis. All patients presented with gait disturbance, but recovered well postoperatively except for one who needed rehabilitation of the lower extremities. This approach provides a greater access to the anterior thoracic canal, and can achieve effective anterior decompression, and a good outcome for thoracic spinal disease if recognized early.

Female↗
PubMed1994

Strategies to improve the outcome of carotid endarterectomy.

The outcomes of carotid endarterectomy (CEA) including long-term results in 121 patients (126 procedures) were retrospectively analyzed to identify the causes of operative morbidity. The angiographic internal carotid artery (ICA) stenosis was severe (> 70%) in 62 patients and moderate (50-70%) with ulceration in 64. The arterial wall was sutured primarily in 91 patients and with patch graft in 35. The outcomes 3 months after operation were good recovery in 86 patients, moderately disabled in 20, severely disabled in 11, and death in four. Three patients suffered operative morbidity (2.5%). During follow-up, three patients (2.6%) suffered transient ischemic attack on the operative side due to middle cerebral artery stenosis (50%) or ICA occlusion at the origin, and recurrent stenosis (40%) of the common carotid artery and ICA (1 each). In the latter two cases, the artery was primarily sutured. Improved therapeutic results require use of patch vein graft for the arterial wall suture, checking of the CEA patency, and prevention of intracranial ischemic events and hemorrhage due to associated lesions.

Adult↗
PubMed1994

The I domain is essential for echovirus 1 interaction with VLA-2.

VLA-2, the alpha 2 beta 1 integrin, mediates cell adhesion to collagen and laminin, and is the receptor for the human pathogen echovirus 1. Because of its similarity to domains present in other proteins that interact with collagen, a 191 amino acid region within the alpha 2 subunit (the I domain) has been proposed as a potential site for ligand interactions. Although the alpha 2 subunits of human and murine VLA-2 are 84% identical, human alpha 2 promotes virus binding whereas murine alpha 2 does not. We used murine/human chimeric alpha 2 molecules to identify regions of the human molecule essential for virus binding. Virus bound efficiently to a chimeric protein in which the human I domain was inserted into murine alpha 2, indicating that the human I domain is responsible for specific virus interactions. Monoclonal antibodies that inhibited virus attachment all recognized epitopes within the human I domain, further suggesting that virus interacts with this portion of the molecule. Similarly, antibodies that prevented VLA-2-mediated cell adhesion to collagen also mapped to the I domain. These results indicate that the I domain plays a role in VLA-2 interactions both with virus and with extracellular matrix ligands.

Amino Acid Sequence↗
PubMed1994

Recurrence of ICA-PCoA aneurysms after neck clipping.

Between 1975 and 1992, 2211 patients underwent aneurysmal neck clipping at the Nara Medical University clinic and associated hospitals. The aneurysm in 931 of these patients was situated at the junction of the internal carotid artery (ICA) and posterior communicating artery (PCoA). Seven patients were readmitted 4 to 17 years after the first surgery because of regrowth and rupture of an ICA-PCoA aneurysmal sac that had arisen from the residual neck. On angiograms obtained following aneurysmal neck clipping, a large primitive type of PCoA was demonstrated in six patients and a small PCoA in one. A small residual aneurysm was confirmed in only two patients and angiographically complete neck clipping in five. Recurrent ICA-PCoA aneurysms were separated into two types based on the position of the old clip in relation to the new growth. Type 1 aneurysms regrow from the entire neck and balloon eccentrically. In this type, it is possible to apply the clip at the neck as in conventional clipping for a ruptured aneurysm. Type 2 includes aneurysms in which the proximal portion of a previous clip is situated at the corner of the ICA and aneurysmal neck and the distal portion on the enlarged dome of the aneurysm, because the sac is regrowing from a portion of the residual neck. In this type of aneurysm, a Sugita fenestrated clip can occlude the residual neck, overriding the old clip. Classifying these aneurysms into two groups is very useful from a surgical point of view because it is possible to apply a new clip without removing the old clip, which was found to be adherent to surrounding tissue.

Adult↗
PubMed1994

Hepatocyte growth factor is a potent promoter of mitogenesis in cultured rat visceral glomerular epithelial cells.

Hepatocyte growth factor (HGF) was originally identified as an hepatotrophic factor inducing liver regeneration, and was also recently found to stimulate mitogenesis of various epithelial cells. In the present study, we examined the mitogenic effects of native and recombinant HGF on cells of rat visceral glomerular epithelial cell line (SGE1). Native and recombinant HGF each stimulated DNA synthesis in and growth of SGE1 cells to a remarkable degree. These mitogenic activities were dose-dependent, being detectable at 2.5 ng/ml and maximal at 20 ng/ml. Over 30% of SGE1 cells tested were shifted to S-phase by HGF alone, as judging by labeling index values. DNA synthesis stimulated by native or recombinant HGF was high at low SGE1 cell density and was strongly suppressed at high cell density. DNA synthesis in and growth of SGE1 cells were stimulated more strongly by recombinant HGF than by native HGF. In addition, the effects of recombinant HGF and epidermal growth factor were additive, while transforming growth factor-beta 1 strongly inhibited the stimulation of DNA synthesis by recombinant HGF. These findings suggest that HGF may play a role in controlling visceral glomerular epithelial cell growth.

Animals↗
PubMed1994

[A case of psittacosis with prolonged lymphocytosis in bronchoalveolar lavage fluid after resolution of pneumonia].

A 52-year-old man was admitted to another hospital with complaints of fever and dyspnea. Chest roentgenogram revealed bilateral widespread infiltrative opacities, and laboratory examinations showed severe hypoxia, hepatic injury and acute renal failure. In addition, hemosputum and eruption appeared, and he was transferred to our department because of the development of multi-organ failure. Moreover, about 2 weeks prior to admission, a budgerigar he had been breeding died. Although the treatment was supportive therapy alone, the abnormal shadow on chest roentgenogram and laboratory findings improved markedly. Thereafter, we made the diagnosis of psittacosis, because the serum titer of a complement fixation test against Chlamydia rose from 1:8 on admission to 1:512 after 2 weeks. On admission, PMN and lymphocyte populations increased in bronchoalveolar lavage fluid (BALF), and 2 weeks later lymphocytes alone increased markedly. Thereafter, we observed lymphocytosis in serial BALF findings for 12 weeks. These findings indicate that lymphocyte alveolitis persisted long after the pneumonia had resolved. Moreover, Ga scintigraphy also revealed accumulation in the filed of shadows which had been absorbed and disappeared on the chest roentgenogram. These results suggest that lymphocytes play a leading role in immune host defenses and that immunological reactivity is prolonged in psittacosis.

Bronchoalveolar Lavage Fluid↗
PubMed1994

[Autopsy case of amyloidosis with marked cardiac and pulmonary lesions associated with myeloma, initially presenting with muscle weakness].

A 69-year-old man presented initially with muscle weakness of the bilateral lower limbs. Chest roentgenogram showed diffuse reticulonodular shadows, bilateral hilar lymphadenopathy, and dullness of bilateral costophrenic angles. Chest CT showed thickening and irregularity of vascular shadows, and thickening of bronchial walls. On the first admission we could not diagnose pulmonary or muscle lesions. He was subsequently admitted for the deterioration of congestive heart failure, but there was no improvement. Myocardial biopsy demonstrated deposition of amyloid in the cardiac muscular tissue. Autopsy revealed amyloid deposition in pulmonary vasculature, alveolar septal walls and pleura. Amyloid deposition was also recognized systemically in skeletal muscles, lymph nodes, liver, kidney, spleen, stomach, and intestines. We recognized about 20% IgA lambda-positive plasma cells with atypia, and myeloma-associated amyloidosis diagnosed. This case was classified as diffuse alveolar septal form and pleural form of pulmonary amyloidosis. We could find only a few reports of pleural form, which exhibits an interesting distribution.

Aged↗
PubMed1993

Role of the alpha subunit cytoplasmic domain in regulation of adhesive activity mediated by the integrin VLA-2.

To investigate the role of the alpha subunit cytoplasmic domain in the regulation of VLA-2 functional activity, we expressed several chimeric and deleted forms of the alpha 2 subunit in two different human cell lines, K562 and RD. Each mutant construct formed surface VLA-2 heterodimers as efficiently as wild type alpha 2 subunit, except for a construct (X2CO1127) truncated just before the consensus GFFKR cytoplasmic domain motif, that was not expressed at the cell surface. Truncation of the alpha 2 cytoplasmic domain just after the GFFKR motif resulted in a complete loss of constitutive activity of VLA-2 in RD cells. If the integrin was already constitutively inactive, as in K562 cells, the cytoplasmic domain deletion had no effect. In both K562 and RD cells, cytoplasmic tail deletion eliminated up-regulation of adhesion in response to the phorbol ester, phorbol 12-myristate 13-acetate (PMA). In comparison, exchange of the alpha 2 cytoplasmic domain with the alpha 4 or alpha 5 cytoplasmic domains had no effect on constitutive activity (in RD cells), or on constitutive inactivity (in K562 cells) and did not eliminate PMA-stimulated activity (in K562 or RD cells). These results clearly demonstrate that the cytoplasmic domain of an alpha chain (not necessarily from alpha 2 itself) is required to maintain VLA-2 constitutive activity and to allow a responsiveness to PMA stimulation. In cases where VLA-2 was either constitutively inactive (as in K562 cells) or inactive due to cytoplasmic domain deletion (e.g. in RD cells), agents such as Mn2+ or the anti-beta 1 monoclonal antibody TS2/16 caused a marked increase in adhesive function, thus proving that the integrins were not irreversibly inactive, and that cellular regulatory constraints could be bypassed by extracellular stimuli.

Antibodies, Monoclonal↗
PubMed1993

Distribution of integrins and their matrix ligands in osteogenic sarcomas.

We studied the expression of the members of the beta 1 integrin family and extracellular matrix ligands in osteosarcoma tissues. Immunostaining of primary osteosarcomas with use of specific antibodies for alpha 1-alpha 6 integrin subunits, fibronectin, type-I collagen, and laminin gave characteristic patterns: despite the diffuse expression of type-I collagen in all 16 osteosarcomas, collagen receptors were detected in only one. Laminin and laminin receptors were expressed poorly. In contrast, the alpha 4 and alpha 5 fibronectin receptors were found in 100 and 75%, respectively, which correlates very well with the strong expression of fibronectin in the stroma. The other ligand for alpha 4, vascular cell adhesion molecule-1, was not expressed in the seven specimens tested. Therefore, primary osteosarcomas closely interact with fibronectin through alpha 4 and possibly alpha 5 subunits of the beta 1 integrin. We also examined the expression of integrins in six metastatic foci in five patients. Some change for the expression was detected in all six specimens, however, the change varied. In contrast, osteosarcoma cells obtained from invasive portions of tumors exhibited new and augmented expression of certain integrins in two of the three cases in which their ligands were also expressed.

Adolescent↗
PubMed1993

Suprasellar embryonal carcinoma which developed ten years after local radiation therapy for pineal germinoma.

We recently encountered a case of suprasellar embryonal carcinoma which developed 10 years after local radiation therapy for pineal germinoma. This 29-year-old male was admitted because of abnormal behavior, disturbed consciousness, and increased intracranial pressure. Computed tomography and magnetic resonance imaging disclosed a tumor spreading from the suprasellar region to the third ventricle and the anterior horn of the left lateral ventricle, accompanied by fresh hemorrhage within the tumor. He underwent subtotal removal of the tumor, followed by chemotherapy with cisplatin and etoposide. The tumor was histologically rated as embryonal carcinoma with differentiation into yolk sac tumor and choriocarcinoma.

Adult↗
PubMed1993

Infection by echoviruses 1 and 8 depends on the alpha 2 subunit of human VLA-2.

Anti-VLA-2 antibodies protected HeLa cells from infection by echoviruses 1 and 8 but not from infection by other echovirus serotypes. Echoviruses 1 and 8 bound to and infected nonpermissive hamster cells transfected with the alpha 2 subunit of human VLA-2. These results indicate that the human alpha 2 subunit is critical for infection by echoviruses 1 and 8 but that other echovirus serotypes must bind receptors other than VLA-2.

Animals↗
PubMed1993

Quantitative cytology of nasal secretions under various conditions.

Quantitative cytology was performed in nasal secretions of normal control (NC), seasonal allergic rhinitis in season (SAR), perennial allergic rhinitis (PAR), chronic sinusitis with mucoid secretion (MS), and chronic sinusitis with mucopurulent secretion (MPS). The majority of inflammatory cells were neutrophils in NC, MS, and MPS; the majority were eosinophils in SAR and PAR. The concomitant appearance of inflammatory cells in nasal secretions was found, i.e., there were significant correlations between neutrophil and eosinophil counts in MPS, and between eosinophil and basophil counts in SAR. The eosinophil/neutrophil ratio was more than 0.1 in SAR and PAR, but the ratio was less than 0.1 in all NC, all MPS, and in 93% of MS; this indicates that 0.1 in eosinophil/neutrophil ratio is the critical value between allergic and nonallergic nasal diseases.

Adolescent↗
PubMed1993

Dissecting aneurysm of the posterior inferior cerebellar artery--case report.

A 29-year-old male presented with a dissecting aneurysm of the left posterior inferior cerebellar artery manifesting as left lateral medullary syndrome due to brainstem ischemia. Extirpation of the aneurysm and anastomosis of the occipital artery to the posterior inferior cerebellar artery were performed simultaneously. The dissecting aneurysm was confirmed by histological examination of the surgical specimen.

Adult↗
PubMed1993

Efficacy of superficial temporal to middle cerebral artery anastomosis against hemodynamic stroke.

The effect of superficial temporal artery-middle cerebral artery anastomosis on regional cerebral blood flow (rCBF) was measured on 31 patients with ischemic cerebrovascular diseases. rCBF was measured on the precentral and superior temporal gyri during surgery using the thermal diffusion technique. The mean rCBF was significantly lower than controls before anastomosis, but increased significantly after. Severer clinical symptoms were associated with lower rCBF. The rCBF increased significantly in patients with transient ischemic attack, reversible ischemic neurological deficit, and minor and major completed stroke. All 31 patients demonstrated dysautoregulation, both before and after anastomosis. However, the rCBF had increased above the ischemic threshold during hypotension, achieving a reserve capacity to prevent hemodynamic stroke.

Adult↗
PubMed1993

Immunohistochemical and electron microscopic studies of substance P in guinea pig nasal glands.

The distribution of substance P-like immunoreactive (SP-IR) nerve endings in the nasal gland of the guinea pig was studied by using histochemical techniques to detect mucous glycoprotein and immunohistochemical techniques for SP, in combination with electron microscopy. Most nasal glands were negative for both AB and periodic acid-Schiff (PAS) staining. The SP-IR nerve fibers were found to form a network around these glands. The SP-IR nerve endings were located in the region between interdigitated cytoplasmic folds of acinar cells and along the cell surface, as well as in the intercellular spaces of proximal ducts. The acini which closely contacted with SP-IR nerve endings were serous in type. Our results suggest that substance P may contribute to the regulation of serous gland secretion in the guinea pig nasal mucosa.

Animals↗
PubMed1993

Rapid and severe proteinuria induced in rats by antibody against cultured rat glomerular epithelial cells.

The aim of this study was to investigate the role of glomerular visceral epithelial cell (GEC) antigens in the induction of proteinuria. An antibody (anti-GECIg) was produced by rabbit immunization with membrane extracts prepared from a clonal GEC line, SGE1, from the isolated rat renal glomeruli. A one-shot intraperitoneal injection of anti-GECIg (day 0) induced rapid and severe proteinuria in rats, reaching a peak on day 2 (mean value, 425 mg/24h), then gradually decreased to normal levels by day 10. By direct immunofluorescence, fine granular binding of anti-GECIg along the glomerular capillary walls was observed within 24 h. Electron microscopy and immunoelectron microscopy revealed GEC alterations consisting of extensive retraction of the foot processes, vacuolar changes in the cytoplasm, microvillous transformation of the cell surface, and binding of anti-GECIg to the surface of the foot process, mainly to its soles. Two major components with Mr of 108,000 and 39,000 were identified by immunoblotting assay using SGE1 cell membrane extracts and anti-GECIg. This model of rat nephropathy induced by anti-GECIg hopefully will lead to a greater understanding of the mechanism by which proteinuria is induced and developed.

Animals↗
PubMed1993

[A case of status asthmaticus complicated by with pneumoperitoneum during mechanical ventilation therapy].

A 46-year-old woman was admitted to our hospital for a severe asthma attack. On admission, systemic cyanosis was observed, and her consciousness state was drowsy. Arterial blood gas showed severe respiratory acidosis, hypoxia, and hypercapnea, with pH, PaO2, and PaCO2 of 7.163, 29.9 torr and 81.3 torr, respectively. Immediately, mechanical ventilation was commerced but on the third hospital day pneumomediastinum and subcutaneous emphysema appeared, and on the sixth day pneumoperitoneum also appeared. The chest CT scan on the sixth day showed free air around bilateral internal mammary vessels. This indicated that air moved from the mediastinum into the peritoneal cavity through an anterior route, via the sternocostal triangle formed by the xiphoid origins of the diaphragm medially and the costal origins laterally.

Female↗