We attempted multilocational hepatocyte transplantation (HCTx) including hepatocyte-bearing polyurethane foam (PUF) to treat congenitally ascorbic acid (AsA) biosynthetic enzyme-deficient (ODS-od/od) rats. Hepatocytes isolated from the liver of congeneic rats were transplanted into the portal vein (Pv), spleen (Sp), omentum (Om), and mesentery (Ms). Hepatocyte-bearing PUF was transplanted into the Om and Ms. Experimental groups were divided into four groups (group I; Pv + Sp, group II; Pv + Sp + Om + Ms, group III; Pv + Sp + hepatocyte-bearing PUF, group IV; control). The average serum AsA level of the surviving rats in group II and III was significantly higher than that in group I 3 mo after HCTx. Histological examination showed small foci of surviving hepatocytes in the Om and Ms tissues and in the connective tissue in the PUF. ODS-od/od rats survived for a long time by multilocational HCTx.

Animals↗

PubMedDate not supplied

Developmental expression of cytochrome P450S within intrasplenically transplanted fetal hepatocytes.

Fetal hepatocytes were harvested at day 20 of gestation from spontaneously hypertensive rats (SHR) and then transplanted into recipient adult SHR spleens. Morphological examination of the recipient spleens revealed that, after 4 and 10 wk, large masses of hepatocytes were present in the red pulp with apparent cord-like structures. Larger batches of hepatocytes were observed in the spleens at 10 wk after than at 4 wk after transplantation. Of major significance was the fact that hepatocyte transplanted spleens were able to express several families of cytochrome P450 (cyto P450) proteins 2-10 wk after transplantation. Immunochemical determinations revealed that cytos P450 IA1, P450 IIB1, P450 p, P450 HLp, and P450 LA omega could be detected without any prior induction. All were intensely expressed 6 wk after transplantation; however, P450 IA1 and P450 IIB1 did not appear to be expressed by 2 wk after transplantation. Although cytos P450 p and P450 HLp did not appear to be expressed by 10 wk after transplantation, they were induced with dexamethasone at that time. Cyto P450 LA omega and peroxisomal acyl CoA oxidase were expressed 6 wk after transplantation in a 70% hepatectomized host. These results demonstrate that fetal hepatocytes can be successfully transplanted into the spleens of recipients and that the fetal hepatocytes appear to grow and develop cyto P450 metabolizing systems.

Animals↗

PubMedDate not supplied

Immobilization of rat hepatocytes on multiporous microcarriers with larger pores and their metabolic activity.

We have investigated the availability of multiporous microcarriers (MCs) for immobilizing isolated rat hepatocytes, but the pore size of MCs was too small (35 microns) for hepatocyte immobilization. In this study, we immobilized isolated rat hepatocytes on MCs with larger pores, and evaluated their metabolic activity. Isolated hepatocytes were immobilized on MCs precoated with collagen by the intermittent stirring method and by aspiration, and the cell-protein content per 100 mg MCs was determined for comparison of these methods. Metabolic activity was evaluated by analyzing NH3 metabolism, urea nitrogen synthesis and glucose synthesis. The aspiration method immobilized significantly more of hepatocytes on MCs than the intermittent stirring method (p < 0.05). A stationary culture of hepatocytes immobilized on MCs showed a similar NH3 metabolism to monolayer cultured hepatocytes, and hepatocytes immobilized on MCs in a floating culture showed significantly higher NH3 metabolism than those in a stationary culture (p < 0.01). However, monolayer cultured hepatocytes showed higher glucose synthesis than hepatocytes immobilized on MCs in a stationary culture (p < 0.01). In conclusion, hepatocytes immobilized on MCs proved to be useful as a bioreactor in a hybrid artificial liver.

Ammonia↗

PubMedDate not supplied

Two-year follow-up study comparing primary vitrectomy with scleral buckling for macula-off rhegmatogenous retinal detachment.

PURPOSE: To compare the anatomic and visual outcomes achieved by scleral buckling and primary vitrectomy for the repair of macula-off rhegmatogenous retinal detachment. METHODS: The records were reviewed for a consecutive series of 167 patients (167 eyes) who were initially treated with scleral buckling or pars plana vitrectomy for primary macula-off retinal detachment. Patients were treated between January 1993 and December 1996. After adjustments for preoperative characteristics, data from 102 cases (55 scleral buckle cases and 47 primary vitrectomy cases) were used for the final comparison. There had been a minimum follow-up period of 24 months. RESULTS: No significant differences in single-procedure reattachment incidence (91%), final success incidence (100%) and incidence of postoperative proliferative vitreoretinopathy development (4%) were observed between the two treatment groups. Preoperative visual acuity, preoperative intraocular pressure, and duration of macular detachment were the three best predictors of postoperative visual recovery in both groups. Favorable overall visual recovery was obtained postoperatively, with no significant differences between the two groups throughout the follow-up period. However, in the eyes with poor preoperative visual acuity (<0.1), ocular hypotony (intraocular pressure <7 mm Hg), or prolonged macular detachment (more than 7 days), visual recovery in the primary vitrectomy group was significantly better (P <.05) than in the scleral buckle group from the first postoperative month. CONCLUSION: Both procedures achieved favorable anatomic and visual outcomes in the majority of patients with primary macula-off retinal detachment. Primary vitrectomy may be more effective than scleral buckling for achieving early visual rehabilitation in cases complicated by poor preoperative vision, ocular hypotony, and prolonged macular detachment.

Adult↗

PubMedDate not supplied

Differential effects of protein tyrosine kinase inhibitors on interferon-gamma-induction of major histocompatibility complex class II and intercellular adhesion molecule-1 expression in human corneal epithelial cells.

PURPOSE: Interferon (IFN)-gamma induces major histocompatibility complex (MHC) class II and intercellular adhesion molecule-1 (ICAM-1) expression on human corneal epithelial (HCE) cells. So far, it has not been clarified whether both inductions by IFN-gamma use the same signal transduction pathway. Therefore, in the present study, we tried to determine the significance of the protein tyrosine kinase (PTK)-dependent signaling pathway in the induction of both MHC class II and ICAM-1 expression by IFN-gamma in cultured HCE cells. METHODS: Cultured HCE cells were treated with human recombinant IFN-gamma. The induction of protein tyrosine phosphorylation of proteins including PTKs, janus kinase (JAK)1, and JAK2, was examined by Western blotting and immunoprecipitation. The effects of treatment of HCE cells with specific PTK inhibitors on IFN-gamma-induction of MHC class II and ICAM-1 expression were examined by flow cytometry. RESULTS: IFN 1 (Interferon) induced tyrosine phosphorylation of multiple substrates, particularly that of 75,000; 90,000; 130,000; and 160,000 molecular weight proteins including JAK1 and JAK2 in cultured HCE cells. The PTK inhibitors, herbimycin A and genistein, inhibited tyrosine phosphorylation of those proteins. Also, these PTK inhibitors prevented IFN-gamma-induction of MHC class II synthesis and surface expression. However, neither herbimycin A nor genistein had any effect on IFN-gamma-induction of ICAM-1 expression. CONCLUSIONS: Tyrosine phosphorylation of proteins including JAK1 and JAK2 is essential for IFN-gamma-induction of MHC class II expression, but not critical for that of ICAM-1 expression in cultured HCE cells. In addition, it is suggested that the IFN-gamma-induction of MHC class II requires PTK activities not only in the primary JAK-signal transducers and activators of transcription (STAT) pathway but also in the subsequent pathway mediated by IFN-gamma-induced intermediate proteins.

Benzoquinones↗

PubMedDate not supplied

Immunosuppressive effect of cholera toxin B on allergic conjunctivitis model in guinea pig.

PURPOSE: To investigate the new method of immunotherapy using cholera toxin B (CTB) in experimental allergic conjunctivitis. METHODS: We used 21 white Hartley guinea pigs. The animals were sensitized by intraperitoneal injection of ovalbumin (100 microg/mL) and albumin hydroxide (5 mg/mL) repeated after an interval of 2 weeks. One week after the second injection, conjunctivitis was induced by topical instillation of ovalbumin (5 mg/mL). The animals were divided into two groups, CTB group and control group. The CTB group underwent pretreatment of topical instillation of CTB (4 microg/30 mL) and ovalbumin (10 microg/30 mL), three times a day for 3 days, 1 week before the intraperitoneal injection. The control group did not undergo the pretreatment. Clinical examination was performed at 0.5, 6, and 24 hours after the development of conjunctivitis. Histological examination was performed at 6 and 24 hours. RESULTS: Both groups developed palpebral and bulbar edema with hyperemia 30 minutes after instillation of ovalbumin. The allergic reaction score was significantly less in the CTB group than in the control group (Mann-Whitney U-test: P <.01). The clinical reactions subsided after 6 hours. The CTB group showed less eosinophilic infiltration in the conjunctiva and the limbus, particularly in the conjunctival epithelium, than the control group at 6 and 24 hours. CONCLUSION: Pretreatment with topical CTB and antigen suppresses clinical and histological findings in experimentally induced allergic conjunctivitis.

Animals↗

PubMedDate not supplied

Immunohistochemical study on follicular dendritic cell of conjunctiva-associated lymphoid tissue.

We performed an immunohistochemical study of follicular dendritic cells (FDC) in the follicular area of the conjunctiva-associated lymphoid tissue (CALT). Hartley guinea pigs were sensitized with a topical application of an emulsion of ovalbumin and Freund's complete adjuvant in the eye. They were divided into four groups. The control (group A) underwent no sensitization. The sensitized animals were studied at 1 week (group B1) or 2 weeks (group B2) after the sensitization. Additional sensitization at 1 week after the initial sensitization was also performed (group C). Histological methods included methylgreen pyronine staining, alpha-naphthylacetate esterase staining, and enzyme-antibody method against S-100 protein. The uptake of topically applied peroxidase-anti-peroxidase (PAP) in CALT was also examined histologically. In each group, positive reticular patterns by alphanaphthyl acetate esterase staining and immunoperoxidase staining with anti-S-100 protein antiserum were found in the CALT follicular area. The positively stained cells were found to be dendrite cells by immunoelectronmicroscopy. An uptake of PAP was found in the CALT follicular area, suggesting the function of trapping and retaining antigen-antibody complex by FDC. It was concluded that dendritic cells in the CALT follicular area were identified to be FDC.

Animals↗

PubMedDate not supplied

Familial case of keratoconus with corneal granular dystrophy.

A family with keratoconus combined with corneal granular dystrophy is reported. The patients are a mother and her two sons. The mother and her elder son have both keratoconus and corneal granular dystrophy; the younger son has keratoconus. Thus, the keratoconus in this family is thought to be of autosomal dominant inheritance. These familial cases suggest that the gene loci for both diseases localize in proximity or have a close relationship.

Adult↗

PubMedDate not supplied

A 10-year review of penetrating keratoplasty.

PURPOSE: To survey the changes in indications for penetrating keratoplasty (PKP) and re-evaluate the risk factors for allograft rejection and graft failure. METHODS: We evaluated the records of 396 eyes of 335 patients who had undergone PKP at the Tokyo University Hospital between 1987 and 1997. Clinical results were analyzed by the Kaplan-Meier life table method and the log-rank test. RESULTS: The overall rates of graft survival and rejection-free graft survival at 10 years were 72.2% and 76.8%, respectively. The rates of graft survival and rejection-free graft survival were 98.8% and 86.6% in keratoconus, 87.0% and 56.5% in herpetic keratitis, 76.9% and 73.1% in corneal dystrophy and degeneration, 69.4% and 80.6% in nonherpetic keratitis, 62.5% and 75.0% in chemical burns, 61.8% and 72.1% in regrafting, and 51.1% and 79.8% in bullous keratopathy, respectively. The graft survival rates were statistically higher in the PKP alone group than in the combined operation group. The graft survival and rejection-free graft survival rates were statistically higher in the first operation group than in the regrafted group, and in the avascular cornea group than in the vascular cornea group. CONCLUSIONS: We recognized changes in indications for PKP. Combined operation, reoperation, and vascularization of recipient cornea were risk factors for graft failure.

Adolescent↗

PubMedDate not supplied

Beneficial effect of hepatic stimulatory substances on the survival of intrasplenically transplanted hepatocytes.

Intrasplenic hepatocyte transplantation has been demonstrated to have a tentative role in treating experimental liver disease, but methods for promoting the rapid proliferation of intrasplenic hepatocytes are still quite limited. In this study, hepatic stimulatory substances (HSS) obtained from regenerating porcine livers were injected directly into the subcutaneously translocated spleens of recipient rats that had received intrasplenic hepatocyte transplantation. The clusters of intrasplenic hepatocytes contained more than 100 cells, and formed cord structures at 2 wk after transplantation, and the hepatocytes still survived at 6 wk in the HSS-treated rats. In contrast, the clusters contained less than 10 hepatocytes at 2 wk after transplantation, and no surviving hepatocytes was observed at 4 and 6 wk in control rats. Additionally, marked proliferation of bile ductular-like structures appeared around the clusters of surviving hepatocytes in the splenic red pulp of the HSS-treated rats, but were not found in control rats at 4 and 6 wk after transplantation.

Animals↗

PubMedDate not supplied

Curvilinear pigmentary lesions in a rod-cone dystrophy.

PURPOSE: To report a peculiar curvilinear pigmentary lesion in the peripheral fundus in a rod-cone dystrophy. METHODS: Observational case report. Fundus examination of a 57-year-old woman who was known to have a generalized rod-cone dystrophy since she was 8 years old. RESULTS: The peripheral fundus examination revealed a curvilinear lesion which resembles a well-known finding associated with a presumed ocular histoplasmosis syndrome or multifocal choroiditis. CONCLUSIONS: The differential diagnosis of a peculiar curvilinear pigmentary lesion in the peripheral fundus may be expanded to include a generalized rod-cone dystrophy.

Choroiditis↗