Biomedical subjects

J Iida

Publications and source records attributed to J Iida.

At least 37 records · Page 2Linked to original sources

PubMed1999

Effects of aging on oxytalan fibre in mouse periodontal ligament.

The reactions of periodontal tissues to the mechanical stimulation of teeth seem to be different in patients of different ages. Although the effects of aging on other structures of the periodontal tissues, i.e., collagen fibre, bone, and cementum, have been reported, there is very little information available concerning the effects of aging on periodontal oxytalan fibre, which is reportedly the only elastic element in the human periodontal ligament. The purpose of this research was to clarify the aging related changes in the distribution of oxytalan fibres in the periodontal ligament of mice. Histological sections of the periodontal ligament of the lower first molar of 10-week-old (control group) and 1-year-old (aged group) ICR mice were specifically stained for oxytalan fibres with aldehyde fuchsin after preoxidization, and observed by light microscopy and confocal laser scanning microscopy (CLSM). In the aged group, oxytalan fibres seemed to be more prevalent around blood vessels in comparison with the control group. Furthermore, CLSM clearly showed that oxytalan fibres in the aged group were relatively more tortuous and complex than those in the control group. This tortuosity and complexity might imply that the oxytalan fibres in aged mice have lost a considerable amount of their original elasticity. While further study of these changes is required, these results may help orthodontists to establish better treatment strategies and methods for adult orthodontic patients.

Adult↗

PubMed1998

A role of chondroitin sulfate glycosaminoglycan binding site in alpha4beta1 integrin-mediated melanoma cell adhesion.

We have previously reported that alpha4beta1 (but not alpha5beta1) integrin-mediated melanoma cell adhesion is inhibited by removal of cell surface chondroitin sulfate glycosaminoglycan (CSGAG), suggesting that melanoma chondroitin sulfate proteoglycan plays a role in modulating the adhesive function of alpha4beta1 integrin. In the current study, we demonstrated that alpha4beta1 integrin binds to CSGAG. We have identified a peptide from within alpha4 integrin termed SG1 (KKEKDIMKKTI) that binds to cell surface melanoma chondroitin sulfate proteoglycan, indicating that SG1 represents a CSGAG binding site within the alpha4 integrin subunit. Soluble SG1 inhibits alpha4beta1 integrin-mediated human melanoma cell adhesion to CS1. Polyclonal antibody generated against the peptide inhibits melanoma cell adhesion to CS1, and the inhibition is reversed by Mn2+ and an activating monoclonal antibody anti-beta1 (8A2). Additionally, pretreatment of cells with anti-SG1 IgG inhibits the expression of the monoclonal antibody 15/7 epitope in the presence of soluble CS1 peptide, suggesting that anti-SG1 IgG prevents ligand binding by alpha4beta1 integrin. These results demonstrate that alpha4beta1 integrin interacts directly with CSGAG through SG1 site, and that this site can affect the ligand binding properties of the integrin.

Antibodies↗

PubMed1998

Dural arteriovenous malformation of the anterior cranial fossa occurring after bifrontal craniotomy.

A case of dural arteriovenous malformation of the anterior cranial fossa developing after bifrontal craniotomy is reported. The nidus was fed mainly by the left anterior ethmoidal artery. It was drained into the right sylvian vein and superior ophthalmic vein with patency of the superior sagittal sinus. A left frontal hemorrhage resulted from the nidus itself. This is the first reported case of an acquired dural arteriovenous malformation of the anterior cranial fossa verified by angiography. This rare lesion is discussed with regard to its etiology.

Cerebral Angiography↗

PubMed1997

Interlocking-clipping technique for giant aneurysms of the internal carotid artery: technical case report.

OBJECTIVE AND IMPORTANCE: Direct clipping of giant intracranial aneurysms is sometimes difficult. A unique technique using multiple fenestrated clips for closing a giant aneurysm is described. CLINICAL PRESENTATION: A 65-year-old woman presented with a 10-month history of headache and gait disturbance. Cerebral angiography disclosed an unruptured giant aneurysm of the right internal carotid artery. INTERVENTION: Surgical exposure confirmed the presence of a giant aneurysm with the splaying and incorporation of the parent artery and a number of perforating arteries originating from the dome. Four angled and three straight fenestrated clips were applied in tandem to the aneurysm to reconstruct the parent artery and preserve the perforating vessels. Through their blades and heads, the closely arranged clips were successfully interlocked. CONCLUSION: This "interlocking-clipping" technique is a modification of the tandem clipping technique. The aim of this approach is to enhance closing pressure and allow a more stable "seating" of the clips in giant cerebral aneurysms.

Aged↗

PubMed1997

A study of cognitive development and behavior problems in mentally retarded children.

Cognitive development in seventy-one mentally retarded children (19 autistic, 52 non-autistic; aged 7-19 years) from a school for handicapped children was studied, using Ohta's scale for evaluating cognitive development level based on language comprehension (Ohta's stage), and other developmental scales. Behavior problems were also examined. The present study reports on the utility of Ohta's stage in non-autistic children, and the relationship between cognitive development level and behavior problems in mentally retarded children. In non-autistic children, there were temporal correlations between Ohta's stage and other development scales (a standard developmental test, speech development, symbolic play development, imitation development), suggesting that in non-autistic children as well, Ohta's stage may serve well as a scale for cognitive development, and reflect symbolic representational functioning. In non-autistic children, most behavior problems in feeding, elimination and sleeping, hyperkinesis, hypokinesis, stereotyped behaviors, self-injurious behavior and licking were closely associated with cognitive development level, and were more often noted in children of lower cognitive development level rather than only in the severely mentally retarded children. Some behavior problems may often occur in the sensorimotor period and hardly occur in the symbolic representational period.

Adolescent↗

PubMed1997

Recurrent Lhermitte-Duclos disease--case report.

A 43-year-old male presented with recurrent Lhermitte-Duclos disease (LDD), a rare pathological entity of the cerebellum of which the etiology is still controversial. He had undergone subtotal removal of a cerebellar lesion, misdiagnosed as a benign astrocytoma, 8 years previously. Subtotal removal of the recurrent tumor completely resolved the presenting symptoms. Recurrence of LDD is not as rare as generally assumed. Patients with LDD require long-term observation even when the initial treatment appeared curative.

Adult↗

PubMed1997

[A case of primary malignant melanoma of the esophagus].

A case of primary and malignant melanoma of the esophagus was reported. A 64-year-old male complaining of discomfort of anterior chest pain was admitted to our hospital for operation. Findings of upper G-1 X-ray and endoscopic examination revealed suspiciously malignant melanoma. Subtotal thoracic esophagectomy with R III dissection was performed. Operative findings included A0 N2 Pl0 M0 Stage III. Macroscopically it showed black-grayish colored polypoid tumors, 7 cm in size. The typical finding of junctional activity adjacent to the tumor mass and melanocytes were microscopically found. The patient received postoperative systemic chemotherapy, but was died of multiple liver and bone metastases 125 days after surgery. Malignant melanoma of the esophagus has extremely poor prognosis and none of effective therapies has been reported.

Esophageal Neoplasms↗

PubMed1996

CD63 associates with tyrosine kinase activity and CD11/CD18, and transmits an activation signal in neutrophils.

As a member of the tetraspan family, it has been hypothesized that CD63 may be associated with signal transduction; however, its role in leukocyte function is unknown. To examine the potential ability of CD63 to activate neutrophils, the effects of five CD63 mAbs, AHN-16, -16.1, -16.2, -16.3, and -16.5, were examined for their ability to alter neutrophil adhesion to HUVEC monolayers. These CD63 Abs increased neutrophil adhesion to resting and TNF-stimulated HUVEC monolayers. This increase in neutrophil adhesion caused by CD63 Abs was blocked by a CD18 Ab and was associated with up-regulation of CD11/CD18 and down-regulation of CD62L on the neutrophil surface. CD11/CD18 was also found to be associated with CD63. This increase in neutrophil adhesion required physiologic extracellular calcium concentrations at or near the time of CD63 Ab binding. The incubation of CD63 Abs with cells in the absence of calcium for 10 min before repletion of calcium resulted in no increase in neutrophil adhesion. Protein kinase activity was detected in neutrophils associated with CD63. Most of the protein kinase activity associated with these Ags was tyrosine kinase activity, with a lesser amount of threonine and serine kinase activities. Src family kinases Lyn and Hck accounted for much of the associated tyrosine kinase activity. The data suggest that CD63 Ab binding to the neutrophil surface triggers a transient activation signal that requires extracellular calcium and regulates the adhesive activity of CD11/CD18. Associated protein kinase activity may play a role in signal transduction by CD63 to regulate other cell functions.

Animals↗

PubMed1996

Cell adhesion to collagenous matrices.

Cell adhesion to extracellular matrices is fundamental for maintaining normal tissue architecture and function. Many diseases are characterized, in part, by molecular changes in cell adhesion. These changes can occur as a result of modifications of the composition or integrity of the extracellular matrix or as a result of disease associated changes in the expression and/or function of adhesion receptors. Such alterations in cell adhesion can have profound effects on the phenotypic traits of cells, and as a result, these changes in cell adhesion can be of primary importance in facilitating disease-associated breakdown of normal tissue function. This is most apparent in a disease such as cancer, where neoplastic transformation can lead to alterations in tumor cell growth, changes in the composition or integrity of tissue proteins, tumor cell migration, invasion, and ultimately metastasis formation. Understanding the molecular basis of cell adhesion could lead to new insights into the molecular basis of many diseases, leading to better therapies. The purpose of this review is to highlight the role that collagens play in mediating cell adhesion, with an emphasis on the structural features of collagen important for cellular recognition and adhesion. Additionally, we briefly review the major receptors and intracellular signals that are important for cellular recognition of, and adhesion to, collagens.

Amino Acid Sequence↗

PubMed1996

Cell surface chondroitin sulfate proteoglycans in tumor cell adhesion, motility and invasion.

Tumor cell invasion and metastasis is highly dependent on dynamic changes in the adhesion and migration of transformed and malignant cells. As with normal cell adhesion, the adhesion of tumor cells influences their cytoskeletal organization, activation of signal transduction pathways within the cell, and nuclear events leading to changes in mRNA transcription and protein synthesis. Furthermore, as tumor cells invade the circulation, they adhere to activated endothelial cells at sites within the vasculature during arrest and extravasation. Studies in the area of tumor cell adhesion and migration have demonstrated that the recognition of extracellular matrix ligands, or adhesion promoting ligands expressed on neighboring cells (i.e. counter-receptors), involves complex molecular recognition mechanisms. The complexity arises, in part, from the multiple recognition sites that are present within adhesion promoting ligands. Some of these structures within ECM components act by binding integrins, whereas others bind additional receptors such as cell surface proteoglycans. In this sense, adhesion promoting ligands may be considered as informational arrays, that function to modulate cell phenotype by engaging specific combinations of adhesion receptors on the cell surface. Understanding the mechanism(s) by which these receptor 'cluster' modify cell adhesion, motility and growth may lead to novel therapeutic strategies to control tumor cell invasion and metastasis formation. This review will highlight the role that cell surface chondroitin sulfate proteoglycans may play in modulating tumor cell adhesion, migration and invasion, with an emphasis on the relationship between cell surface chondroitin sulfate proteoglycans and integrins.

Cell Adhesion↗

PubMed1996

CD44/chondroitin sulfate proteoglycan and alpha 2 beta 1 integrin mediate human melanoma cell migration on type IV collagen and invasion of basement membranes.

Tumor cell invasion of basement membranes (BM) represents one of the critical steps in the metastatic process. Tumor cell recognition of individual BM matrix components may involve individual cell adhesion receptors, such as integrins or cell surface proteoglycans, or may involve a coordinate action of both types of receptors. In this study, we have focused on the identification of a cell surface CD44/chondroitin sulfate proteoglycan (CSPG) and alpha 2 beta 1 integrin on human melanoma cells that are both directly involved in the in vitro invasion of reconstituted BM via a type IV collagen-dependent mechanism. Interfering with cell surface expression of human melanoma CSPG with either p-nitro-phenyl-beta-D-xylopyranoside treatment or anti-CD44 monoclonal antibody (mAb) preincubation (mAb) preincubation inhibits melanoma cell invasion through reconstituted BM. These treatments also strongly inhibit melanoma cell migration on type IV collagen, however, they are ineffective at inhibiting cell adhesion to type IV collagen. Purified melanoma cell surface CD44/CSPG, or purified chondroitin sulfate, bind to type IV collagen affinity columns, consistent with a role for CD44/CSPG-type IV collagen interactions in mediating tumor cell invasion. In contrast, melanoma cell migration on laminin (LM) does not involve CD44/CSPG, nor does CD44/CSPG bind to LM, suggesting that CD44/CSPG-type IV collagen interactions are specific in nature. Additionally, anti-alpha 2 and anti-beta 1 integrin mAbs are capable of blocking melanoma cell invasion of reconstituted BM. Both of these anti-integrin mAbs inhibit melanoma cell adhesion and migration on type IV collagen, whereas only anti-beta 1 mAb inhibits cell adhesion to LM. Collectively, these results indicate that melanoma cell adhesion to type IV collagen is an important consideration in invasion of reconstituted BM in vitro, and suggest that CD44/CSPG and alpha 2 beta 1 integrin may collaborate to promote human melanoma cell adhesion, migration, and invasion in vivo.

Basement Membrane↗

PubMed1996

The clinical features of Tourette's disorder with obsessive-compulsive symptoms.

Twenty-three patients with Tourette's disorder (13 with obsessive-compulsive symptoms [OCS] and 10 without) were comparatively investigated. In contrast to OCS-free Tourette's disorder patients, those with OCS were found to be characterized by (i) a higher incidence of volatile temper, (ii) a higher incidence of compulsive tics, (iii) a higher incidence of perinatal disorders and brain wave abnormalities, (iv) a higher severity as rated using the Severity Scale, and (v) a higher prevalence of complications, especially of developmental disorders. Of the subjects with OCS-accompanied Tourette's disorder, approximately half had developed OCS by the onset of tics. These findings suggest the likelihood that OCS-accompanied Tourette's disorder is more strongly associated with organic cerebral disorders, independently of sites of tic disorders, than is OCS-free Tourette's disorder.

Adolescent↗

PubMed1996

Immature teratoma in the cerebral basal ganglia of an adult.

A 19-year-old male underwent an emergent operation for a massive brain tumor in the right cerebral basal ganglia. However, brain herniation had already developed and he subsequently died. Histological examination showed the tumor consisted of immature epithelial arrangements and glandular structures, considered as immature teratoma containing choriocarcinomatous components. Such an immature teratoma arising in the cerebral basal ganglia in an adult is very rare.

Adult↗

PubMed1996

Transcutaneous intracordal silicon injection for unilateral vocal cord paralysis.

Unilateral recurrent laryngeal nerve paralysis causes the vocal cord to atrophy, leading to glottic incompetence. The voice is characterized by hoarseness, breathlessness, rapid air escape, ineffective cough and aspiration. Traditional treatments of unilateral vocal cord paralysis include intracordal injection, laryngeal framework surgery, and laryngeal reinnervation for medialization of the vocal cord. In this paper we report on a new technique of transcutaneous intracordal silicon injection in which the injection is made through the thyroid lamina under local anesthesia monitoring fiberscopy. We performed this procedure on 30 patients with unilateral vocal cord paralysis and later evaluated their post-operative voice. The silicon injection resulted in improvement of vocal quality, favorable clearance of sputum, and aspiration control. We found that, since it can be performed under local anesthesia without hospitalization, transcutaneous intracordal silicon injection should be performed as a therapy for treating unilateral vocal cord paralysis.

Administration, Cutaneous↗

PubMed1995

Multiplicity of N-terminal structures of medium-chain alcohol dehydrogenases. Mass-spectrometric analysis of plant, lower vertebrate and higher vertebrate class I, II, and III forms of the enzyme.

Ten different alcohol dehydrogenases, representing several classes of the enzyme and a wide spread of organisms, were analyzed for patterns of N-terminal structures utilizing a combination of conventional and mass spectrometric peptide analysis. Results show all forms to be N-terminally acetylated and allow comparisons of now 40 such alcohol dehydrogenases covering a large span of forms and origins. Patterns illustrate roles of acetylation in proteins in general, define special importance of the class I N-terminal acetylation, and distinguish separate acetylated structures for all classes, as well as a common alcohol dehydrogenase motif.

Acetylation↗

PubMed1995

Spreading and focal contact formation of human melanoma cells in response to the stimulation of both melanoma-associated proteoglycan (NG2) and alpha 4 beta 1 integrin.

In this study, we evaluated the potential role for a specific melanoma-associated chondroitin sulfate proteoglycan core protein, termed NG2, to collaborate with alpha 4 beta 1 integrin in focal contact formation in human melanoma cells. Although melanoma cells adhered to substrata coated with either the alpha 4 beta 1 integrin binding fibronectin synthetic peptide CS1-OVA or anti-NG2 mAbs, no spreading or focal contact formation was observed on either substratum. However, melanoma cells spread and formed focal contacts on "chimeric substrata" coated with CS1-OVA and the anti-NG2 mAb, 9.2.27, indicating that engaging both adhesion receptors changes the adhesion phenotype of melanoma cells by reorganizing the cytoskeleton. The collaboration between the two receptors is specific to fibronectin, since cells adherent on substrata coated with low concentrations of either laminin and 9.2.27 or type IV collagen and 9.2.27 failed to spread, while cells adherent on low concentrations of fibronectin and 9.2.27 exhibited a fully spread morphology. Two selective tyrosine kinase inhibitors, genistein and herbimycin A, totally inhibited cell spreading on the substrata coated with CS1-OVA and 9.2.27, indicating that tyrosine kinase(s) is important for cell spreading and focal contact formation. When cells were cultured on substrata coated with CS1-OVA and 9.2.27, two proteins (M(r) 130,000 and 120,000) were tyrosine phosphorylated in a genistein- and herbimycin A-sensitive fashion. These proteins were not immunologically related to pp125FAK or alpha 4 beta 1 integrin. Importantly, when melanoma cells were cultured on substrata coated with CS1 and then stimulated with 9.2.27-conjugated microsphere beads, formation of focal contacts and stress fibers was also observed, indicating that NG2 can collaborate with alpha 4 beta 1 integrin when each receptor is engaged on distinct and separate substrata. These results demonstrate that NG2 acts as a coreceptor for spreading and focal contact formation in association with alpha 4 beta 1 integrin in melanoma cells and suggest a model in which the NG2 core protein communicates to alpha 4 beta 1 integrin by an inside-out signaling mechanism.

Antibodies, Monoclonal↗

PubMed1995

Clinical features of childhood-onset schizophrenia with obsessive-compulsive symptoms during the prodromal phase.

Thirty-nine patients with schizophrenia, diagnosed according to DSM-III-R, who were under 15 years of age, were studied in two groups; 16 subjects with obsessive-compulsive symptoms during the prodromal phase, and 23 with no obsessive-compulsive disorders. The group with obsessive-compulsive symptoms during the prodromal phase was characterized by a higher ratio of males, higher incidences of perinatal and brain computed tomography (CT) abnormalities, fewer hereditary factors, longer duration of the prodromal phase, and a higher incidence of insidious onset and negative symptoms compared with the group without such prodromal symptoms. Schizophrenic patients with obsessive-compulsive symptoms during the prodromal phase were clinically distinct from those without, which suggests the possibility of subtype categorization.

Adolescent↗

PubMed1995

[Jaw position, head position, body posture: development of an integrated system of examination, Part I].

Recently in the field of clinical orthodontics, there has been increased interest in the relationship between jaw and head position, sleep apnea, and equivocal symptoms occurring in head, neck and shoulder. It has already been determined that a relation exists between head posture and mode of breathing. Since the craniofacial skeleton is supported by the cervical, thoracic and lumbar vertebrae, the head position might have some biomechanical connection to total body posture. Therefore, an integrated system of examining jaw position, head position and body posture is being developed.

Biomechanical Phenomena↗