Biomedical subjects

S Saika

Publications and source records attributed to S Saika.

88 records · Page 5Linked to original sources

PubMed1990

Development and evaluation of the TD97 measles virus vaccine.

The TD97 strain vaccine virus was prepared from the Tanabe strain measles virus by low-temperature passages in primary cell cultures and ultraviolet (UV) mutagenesis. The TD97 strain exhibited the following characteristics: highly temperature sensitive, neither multiplying nor forming any plaques at 40 degrees C in Vero cells; genetically stable, maintaining high temperature sensitivity after ten successive passages in CE cells at 30 degrees C or 35 degrees C; and M proteins of this virus about 1 KD slower in mobility in SDS-PAGE than that of the Tanabe strain. The TD97 strain was further confirmed to be attenuated by an inoculation test into primate brain. In field trials, 752 healthy children were inoculated with a live virus vaccine prepared with this strain, and the following results were obtained: the seroconversion rate was 97% (517/533), and the average HI antibody titer was 2(5.2). An antibody-increasing effect was also observed in children who were initially seropositive. In children who seroconverted, the rates of fever were 15.7% (55/351) for 37.5 degrees C or higher and 4.0% (14/351) for 39 degrees C or higher. The rash rate was 7.7% (27/351), and the incidence of local reaction was 5.4% (19/351). The TD97 strain is thus considered to be suitable in use for an attenuated measles vaccine.

Animals↗

PubMed1990

Presence and distribution of fibronectin on the surface of implanted intraocular lenses in rabbits.

An immunohistochemical study was performed to observe cellular proliferation on the surface of implanted intraocular lenses (IOLs) in rabbit eyes. Rabbits were killed at intervals of 3 days and 1, 2, and 4 weeks after the operation. The IOLs were removed and examined by an immunoperoxidase staining method using antifibronectin (anti-FN) antibodies. The FN immunoreactivity was detected in macrophages and giant cells attached to the IOL surface. Prominent staining was observed in these cells 1 week after the operation, and staining for FN was less intense in the specimens obtained 2 and 4 weeks after implantation. These findings suggest that FN is produced by macrophages and giant cells on the IOL surface and may play an important role in cellular adhesion and motility. FN immunoreactivity decreased with time, which might be related to cellular activity.

Animals↗

PubMed1990

Experimental intraocular lens implantation in the rabbit eye and in the mouse peritoneal space. Part V: Phagocytosis and nuclear patterns of giant cells observed on the implanted lens surface.

The major cellular components on intraocular lenses experimentally implanted in the rabbit eye and in the mouse peritoneal space were examined. They consisted of macrophages and their metamorphosed epithelioid cells with occasional formations of foreign-body giant cells from the fusion of the macrophage-related cells. Lymphocytes, individually and in clusters, were also seen on the lenses implanted in the mouse peritoneal space but rarely on those implanted in the rabbit eye. Macrophages, epithelioid cells, and giant cells exhibited active phagocytosis on the implanted intraocular lenses. These cells phagocytized not only minor foreign particles such as artificially fed latex or carbon colloids but also living cells including erythrocytes, leukocytes, and lymphocytes. The nuclear pattern of the giant cell formation process initially assumed a centrally located nuclear distribution of a foreign-body giant cell type, and then a peripherally located Langhans type distribution when the number of nuclei reached about five in both the mouse peritoneal space and the rabbit eye chamber. Ultra-large giant cells containing a number of nuclei, however, were only observed on lenses implanted in the rabbit eye, demonstrating a difference between the two environments.

Animals↗

PubMed1990

Comparison of the cellular response on intraocular lenses implanted in rabbit eyes with and without extracapsular lens extraction.

Three-piece poly(methyl methacrylate) intraocular lenses (IOLs) were implanted in rabbit eyes with and without lens extraction to examine the cellular response on the IOL surface without the effects of the residual lens cortex. Each rabbit had extracapsular lens extraction (ECCE) with IOL implantation in the posterior chamber of one eye. In the second eye, the IOL was implanted in the anterior chamber without lens extraction. The lenses were removed and studied with light microscopy and scanning electron microscopy one week after surgery. Light microscopic findings revealed a similar cellular response on the surface of the IOLs in both groups. Scanning electron microscopy suggested that the cellular adhesiveness on the IOL surface in the eyes without lens extraction was weaker than in the eyes that had ECCE. Cells on the IOLs in the eyes without lens extraction were flatter and had membranous pseudopodia. It appears that the cells on the IOL surface were caused by a foreign body reaction and that their adhesiveness to the IOL was affected by residual lens cortex.

Animals↗

PubMed1990

[Experimental study of cellular response on the intraocular lens surface in terms of the presence and distribution of fibronectin].

An immunohistochemical study was performed to observe cellular proliferation on the surface of implanted intraocular lenses (IOLs) in rabbit eyes. Rabbits were killed 3-28 days postoperatively. The removed IOLs were examined by an immunoperoxidase staining method using anti-fibronectin antibodies. The immunoreactivity for fibronectin was detected in macrophages and multinucleated giant cells attached to the IOL surface. Prominent stains were observed in these cells 1 week after the operation, and staining for fibronectin was less intense in the specimens 2 and 4 weeks after implantation. Fibronectin is produced by macrophages and multinucleated giant cells on the IOL surface, and might play important role in cellular adhesion and motility. Fibronectin immunoreactivity decreased with time and it may be related to cellular activity.

Animals↗

PubMed1989

[Experimental study of phagocytosis of the cells observed on the surface of intraocular lens].

It has been reported that macrophages adhere to implanted intraocular lens (IOL) in a reaction to the foreign body, and transform themselves into epithelioid cells, fibroblast-like cells, and foreign body giant cells. We attempted to examine the activity of these cells by studying phagocytosis. Extracapsular lens extractions with implantation of posterior chamber IOLs were performed in rabbit eyes. After one week, the implants were removed and incubated in culture medium containing latex beads to investigate phagocytosis of these cells adhering to the implants by light microscopy, scanning and transmission electron microscopy. The cells observed were macrophages, epithelioid cells, fibroblast-like cells, and foreign body giant cells. The round macrophage was most active in phagocytizing latex beads, while the activity was weaker in the epithelioid cells, fibroblast-like cells, and foreign body giant cells. The macrophages on the implants had many ruffles on their surface, and many latex beads adhered to the cell surface. The epithelioid cells and foreign body giant cells had few ruffles with few latex beads on their surface. These results suggested that cellular activity of the macrophages on the implanted IOL might decrease as their shape transformed.

Animals↗

PubMedDate not supplied

Alterations in ultrastructure and c-met expression in a case of ocular epithelial dysplasia following topical mitomycin C treatment.

PURPOSE: Topical mitomycin C (MMC) administration is reportedly effective in treating ocular surface neoplasms such as squamous cell carcinoma. We treated a case of ocular epithelial dysplasia that had spread too diffusely to be completely removed. We examined the ultrastructure of and c-met (hepatocyte growth factor receptor) expression in dysplastic epithelial cells from this case to evaluate the efficacy of MMC treatment. METHODS: Specimens of dysplastic epithelial tissue from the corneo-limbal region of a 62-year-old man were obtained before and after topical application of MMC. Specimens were examined ultrastructurally and immunohistochemically with an antibody against human c-met. RESULTS: Following topical application of MMC, the dysplastic epithelium exhibited multilayered epithelial cells similar to those seen before treatment. However, ultrastructural examination showed tight interdigitation between neighboring cells, with no intercellular spaces. Also, the marked immunoreactivity to c-met in the dysplastic epithelial cells before MMC treatment was decreased after treatment. CONCLUSIONS: Ultrastructural observations indicated a restoration of epithelial cellular differentiation following MMC application. The expression of c-met protein was also reduced. Thus, topical MMC was effective in treating epithelial dysplasia of the ocular surface, with no recurrence 15 months post-therapy.

Administration, Topical↗

PubMedDate not supplied

Corneal epithelial basement membrane after experimental anterior stromal puncture in guinea pigs: immunohistochemical study.

We investigated alterations in the immunolocalization of the components of epithelial basement membrane (BM), type IV collagen, and laminin in guinea pigs subjected to anterior stromal puncture (ASP) of the cornea performed with a standardized needle. Localization of BM components beneath the corneal epithelium was indicated by laminin immunoreactivity. The BM was interrupted by needle punctures immediately after ASP. During healing, type IV collagen immunoreactivity was detected transiently in the BM of some of the ASP-treated corneas, but no reactivity was observed in normal epithelial BM. Development of type IV collagen immunoreactivity was probably caused by an alteration of the alpha-chains or by an unmasking of the antigenicity of this collagen type, which may be related to an increase in the adhesiveness of the epithelium following ASP.

Animals↗

PubMedDate not supplied

Immunohistochemical identification of proteoglycan types in fibrotic human capsules with intraocular lens implants.

Lens capsules become fibrotic after cataract extraction. A variety of extracellular matrix (ECM) components accumulate on these capsules in association with the proliferation of lens epithelial cells. To provide a better understanding of the process of capsular fibrosis, we assessed the types of proteoglycans (PG) in human lens capsules with intraocular lenses (IOL). Lens capsules containing IOLs were removed from 1 patient with proliferative vitreoretinopathy and 1 patient with proliferative diabetic retinopathy. After treatment with chondroitinase ABC, tissue sections were processed for immunohistochemical detection of the proteoglycans including chondroitin, large PG, chondroitin 4-sulfate PG, chondroitin 6-sulfate PG, dermatan sulfate PG, and keratan sulfate PG. Extracellular matrix was found on the inner surface of the capsular bag. In association with what appeared to be proliferating lens epithelial cells, each of the six types of PG was present in the ECM on the capsules. All six types of PG might be involved in the fibrosis and opacification of lens capsules after extraction of the cataract and implantation of the IOL.

Antibodies, Monoclonal↗

PubMedDate not supplied

Pathological findings in lens capsule and silicone intraocular lens extracted from eye with chronic infectious endophthalmitis.

The lens capsule and silicone intraocular lens (IOL) extracted from the eye of a patient with chronic infectious endophthalmitis was examined histopathologically to evaluate the pathology of a capsule and IOL surfaces in the presence of bacterial infection. A 69-year-old man developed an infection in his right eye 4 months after phacoemulsification and aspiration of a cataract and implantation of a silicone IOL. During vitrectomy, the capsule and IOL were extracted and processed for light or scanning electron microscopy. Cryosections of the capsule were subjected to Gram staining and immunohistochemical tests for extracellular matrix components. The lens capsule contained an accumulation of extracellular matrix, including collagen types and fibronectin. A colony of Gram-positive rod bacteria was detected inside the capsular bag. Scanning electron microscopy failed to detect any microorganisms on the IOL surface. Histological examination of cryosections of the extracted capsule confirmed the presence of infection during surgery even though preoperative cultures of intraocular fluid were negative. Immediate antibacterial treatment could be initiated.

Aged↗

PubMedDate not supplied

In-the-bag hyphema after intraocular lens implantation.

In-the-bag hyphema, the collection of blood in the endocapsular space between the posterior capsule and the intraocular lens (IOL), is a rare postoperative complication of IOL implantation in the capsular bag. We report three cases. In Case 1, the hyphema did not obscure the visual axis and thus no treatment was given; the hyphema reabsorbed spontaneously within 3 months Case 2 was successfully treated with a neodymium:YAG (Nd:YAG) laser capsulotomy. Although a fibrin membrane on the IOL's anterior surface in Case 3 made it difficult, an Nd:YAG capsulotomy was performed followed by subsequent YAG laser dissection of the fibrin membrane. We believe that for improved simplicity, safety, and efficacy in such a case, membrane dissection should be done at the time of the capsulotomy.

Aged↗

PubMedDate not supplied

Posterior capsule rupture by blunt ocular trauma.

A patient with posterior lens capsule rupture caused by blunt trauma and in whom the anterior capsule and the remainder of the eyeball structure was intact had phacoemulsification and aspiration of the crystalline lens with implantation of a posterior chamber intraocular lens. Further rupture of the capsule was prevented by the fibrosis, which tightened the margin of the ruptured capsule. This case shows that blunt trauma can rupture the posterior lens capsule, leaving the anterior capsule intact.

Adult↗

PubMedDate not supplied

Disappearance of desmosomal components in rat corneal epithelium during wound healing.

PURPOSE: Epithelial migration is essential for healing of the ablated corneal epithelium. To reveal the mechanism which enables the corneal epithelial cells to dissociate during migration, we investigated the immunolocalization of the components of the desmosome, which is the main constituent of the intercellular junction attaching the intermediate filaments to the cell surface, desmoplakin 1, desmoglein and plakoglobin, in the corneal epithelium during wound healing in rats. METHODS: Under general anesthesia with ether inhalation, Wistar rats (n = 48) underwent removal of the central corneal epithelium of one eye with a small trephine and a scalpel. After various intervals of healing (5 min; 1, 3, 6, 9, 12, 24, 48 h; 1 and 2 weeks), the animals were killed and the affected eye was excised. Cryosections of each anterior segment of the eye were fixed with cold acetone and treated with primary antibodies against desmoplakin 1, desmoglein and plakoglobin. Immunolocalization of these substances was visualized by the peroxidase-diaminobenzidine reaction. RESULTS: A marked immunoreactivity for these desmosome components was detected at the intercellular junction in the normal corneal and conjunctival epithelium. At 6-24 h after epithelial ablation, a weak immunoreactivity for desmoplakin 1 and plakoglobin was observed in the migrating epithelium. At 48 h after epithelial ablation, a marked immunoreactivity for these desmosome components was seen again. At 6-48 h after epithelial ablation, a weak immunoreactivity for desmoglein was observed in the migrating epithelium. At 1 week after epithelial ablation, a marked immunoreactivity for this desmosome component reappeared. The regenerated epithelium gradually exhibited normal immunolocalization of the proteins. CONCLUSIONS: The desmosome components were considered to be degraded or destroyed prior to epithelial migration and reconstructed during healing of the squamous epithelium.

Animals↗

PubMedDate not supplied

Immunolocalization of c-Fos and c-Jun in rat ocular surface epithelium.

We immunohistochemically located c-Fos and c-Jun, the major components of transcription factor activator protein 1 (AP1), in normal epithelia of rat cornea and conjunctiva to determine the expression of these genes in the ocular surface epithelia. Immunoreactivity for c-Fos was detected in the nuclei of basal cells of the limbal and conjunctival epithelia, while that for c-Jun was detected in the cytoplasm of the cells of these epithelia. The corneal epithelium lacked immunoreactivity for either protein. AP1 may have an important role in the maintenance of homeostasis of limbal and conjunctival epithelia.

Animals↗

PubMedDate not supplied

Relationship between formation of a filtering bleb and an intrascleral aqueous drainage route after trabeculectomy: evaluation using ultrasound biomicroscopy.

We evaluated the relationship between the development of filtering bleb and the thickness of the aqueous drainage route beneath the scleral flap in patients who had undergone trabeculectomy. The relationship between the postoperative intraocular pressure and the size of the filtering bleb was also studied. We studied 29 eyes of 21 patients who had been followed for at least 1 (mean 9.9) month after the trabeculectomy. Ultrasound biomicroscopy was used to examine the filtering bleb and aqueous drainage route beneath the scleral flap. The thickness of the aqueous drainage route beneath the center of the scleral flap was found to be correlated with the development of a filtering bleb (r = 0.391, p < 0.05). The size of the bleb was correlated with the intraocular pressure (r = -0.560, p < 0.05) which had not been treated with antiglaucoma medication during follow-up. Thus, preservation of the aqueous drainage route beneath the scleral flap probably influenced the development of a filtering bleb following trabeculectomy.

Adult↗

PubMedDate not supplied

L-asparaginase (Leunase) induced pancreatitis in childhood acute lymphoblastic leukemia.

A major complication of L-asparaginase therapy in acute lymphoblastic leukemia (ALL) is pancreatitis. Among the 915 cases of ALL seen over last 10 years, 19 (2%) developed pancreatitis. Median age was 5.5 years with a median duration of symptoms of 4 weeks. All cases had raised serum amylase and lipase. Pancreatitis was not related to the dose/duration of L-asparaginase therapy. Ultrasonography can be used as a corroborative investigation for diagnosis along with serum chemistries. Close clinical monitoring of children for early diagnosis of this complication is recommended.

Adolescent↗