Publications by authors named "Yutaka Niihara"

We report in this study on the isolation and expansion of neural crest stem cells (NCSCs) from the epithelium of oral mucosa (OM) using reagents that are GMP-certified and FDA-approved for clinical use. Characterization analysis showed that the levels of keratins , , , , , and -specific to OM epithelial cells-were significantly lower in the experimental NCSCs. While was decreased with no statistically significant difference, the earliest neural crest specifier genes , , , , , , and showed a trend in increased expression in NCSCs.

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The present study focuses on investigating the expression of thrombospondin-1 (TSP-1), a natural inhibitor of neovascularization. Immunofluorescent staining was used to detect the expression of TSP-1 in rabbit corneal tissue with vascularization induced by limbectomy. TSP-1 was detected in healthy and Cultured Autologous Oral Mucosal Epithelial Cell Sheet (CAOMECS) grafted rabbit corneas.

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Well-characterized adipose stem cells and chemically defined culture media are important factors that control the production of the cell sheet, used in translational medicine. In this study, we have developed and engineered multilayer adipose stem cell cell sheets (ASCCSs) using chemically defined/serum-free culture media: undifferentiated or differentiated into osteoblasts and chondrocytes. In addition, using the cell sheet transmittance, we estimated the number of cells per cell sheet.

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Purpose: The purpose of the present study is to investigate the expression of aldehyde dehydrogenases (ALDHs) in rabbit corneas with limbal stem cell deficiency (LSCD) and corneas treated with cultured autologous oral mucosa epithelial cell sheet CAOMECS designed to reconstruct the ocular surface with LSCD.

Methods: New Zealand white rabbit autologous oral mucosal epithelial cells were isolated from a buccal biopsy and cultured to be grafted back onto corneas of rabbit model of LSCD. Immunofluorescent staining and Western blot analysis were used to compare the expression of ALDH1A1 and ALDH1A3 in healthy, LSCD-diseased, CAOMECS treated corneas.

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In the field of cell therapy, the interest in cell sheet technology is increasing. To determine the cell sheet harvesting time requires experience and practice, and different factors could change the harvesting time (variability among donors and culture media, between cell culture dishes, initial cell seeding density). We have developed a device that can measure the transmittance of the multilayer cell sheets, using a light emitting diode and a light detector, to estimate the harvesting time.

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The present study reports the feasibility and successful production of rabbit cG-CAOMECS, designed to reconstruct corneal epithelium of patients with bilateral limbal stem cell deficiency. To produce a safe, chemically defined and FDA compliant cG-CAOMECS, oral mucosal epithelial cells were isolated from a biopsy of rabbit buccal tissue and seeded on a cGMP-certified cell culture surface coated with GMP-grade extracellular matrix. A newly designed clinical-grade medium (KaFa™ medium) was utilized to carry out cell expansion.

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The corneal surface is an essential organ necessary for vision, and its clarity must be maintained. The corneal epithelium is renewed by limbal stem cells, located in the limbus and in palisades of Vogt. Palisades of Vogt maintain the clearness of the corneal epithelium by blocking the growth of conjunctival epithelium and the invasion of blood vessels over the cornea.

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Shipping time and shipping delays might affect the quality of the stem cells based engineered "organs." In our laboratory, we have developed a limbal stem cell deficient (LSCD) rabbit model. To reverse the LSCD, we cultured oral mucosal epithelial cells for 2-3 weeks and engineered cultured autologous oral mucosa epithelial cell sheets (CAOMECS), which were grafted on the LSCD cornea.

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The study goals were to engineer and harvest scaffold-free undifferentiated/differentiated multilayer human adipose-derived stem cell (hADSC) cell sheets, in absence of treatment.  The hADSC are seeded in 35 mm culture dishes. At confluence or when multilayer cell sheets are formed, hADSC are treated with predefined differentiation culture media (adipocyte, chondrocyte and osteoblast).

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Purpose: To understand the mechanism of corneal keratin expression and clearance in corneal epithelium with Limbal Stem Cell Deficiency (LSCD). The hypothesis is that LSCD-induced proteasome dysfunction is a contributing factor to keratin aggregation, causing corneal keratin aggresome (CKAGG) formation.

Method: LSCD was surgically induced in rabbit corneas.

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The optimal cell culture method of autologous oral mucosal epithelial cell sheet is not well established for a safe transplantation on to the patients' ocular surface. Animal serum and 3T3 mouse feeder cells are currently being used to stimulate the growth of the epithelial cells. However, the use of animal compounds can have potential side effects for the patient after transplantation of the engineered cell sheet.

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Background: Oxidative stress contributes to the complex pathophysiology of sickle cell disease. Oral therapy with pharmaceutical-grade l-glutamine (USAN, glutamine) has been shown to increase the proportion of the reduced form of nicotinamide adenine dinucleotides in sickle cell erythrocytes, which probably reduces oxidative stress and could result in fewer episodes of sickle cell-related pain.

Methods: In a multicenter, randomized, placebo-controlled, double-blind, phase 3 trial, we tested the efficacy of pharmaceutical-grade l-glutamine (0.

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Purpose: This study focuses on characterizing proteasomes in corneal epithelial cells (CEC) and in cultured autologous oral mucosal epithelial cell sheets (CAOMECS) used to regenerate the ocular surface.

Methods: Limbal stem cell deficiency (LSCD) was surgically induced in rabbit corneas. CAOMECS was engineered and grafted onto corneas with LSCD to regenerate the ocular surface.

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The role of E-cadherin in epithelial barrier function of cultured autologous oral mucosa epithelial cell sheet (CAOMECS) grafts was examined. CAOMECS were cultured on a temperature-responsive surface and grafted onto rabbit corneas with Limbal Stem Cell Deficiency (LSCD). E-cadherin levels were significantly higher in CAOMECS compared to normal and LSCD epithelium.

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This study investigates the therapeutic effects of carrier-free cultured autologous oral mucosa epithelial cell sheet (CAOMECS) transplantation for experimentally induced severe rabbit limbal stem cell deficiency (LSCD). Buccal biopsies were performed and CAOMECS were cultured and transplanted onto diseased corneas. Six-month follow-up examinations indicated that three out of four corneas with CAOMECS grafts showed a decrease in superficial vascularization, while almost all the sham corneas did not show a similar decrease.

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Background: Graves' disease (GD) is associated with hyperthyroidism. Thyrotoxicosis adversely affects multiple organ systems including haematopoiesis. Anaemia occurring specifically in GD has not been systematically studied previously.

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Sickle-cell anemia is one of the most prevalent hereditary disorders with prominent morbidity and mortality. Oxidative phenomena play a significant role in the disorder's pathophysiology. A forumlation of garlic (Allium sativum), AGE, has been reported to exert an antioxidant effect in vitro.

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Garlic has been known to have antiplatelet properties. Because of the lack of major clinical data regarding the safety of concomitant use of garlic supplements and anticoagulants, we decided to evaluate the safety of using garlic extract along with oral anticoagulation therapy. During this project we tested aged garlic extract (AGE), a commercial garlic preparation, with warfarin (Coumadin).

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Background: We have previously demonstrated that therapy with orally administered L-glutamine improves nicotinamide adenosine dinucleotide (NAD) redox potential of sickle red blood cells (RBC). On further analysis of L-glutamine therapy for sickle cell anemia patients, the effect of L-glutamine on adhesion of sickle RBC to human umbilical vein endothelial cells (HUVEC) was examined.

Methods: The first part of the experiment was conducted with the blood samples of the 5 adult sickle cell anemia patients who had been on L-glutamine therapy for at least 4 weeks on a dosage of 30 grams per day compared to those of patient control group.

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Background: Aged Garlic Extract (AGE) reduces multiple cardiovascular risk factors, including blood pressure, cholesterol, platelet aggregation and adhesion, while stimulating nitric oxide generation in endothelial cells. However, no study has evaluated the ability of AGE to inhibit vascular calcification, a marker of plaque formation in human coronary arteries.

Objective: To assess the efficacy of Aged Garlic Extract (AGE) on changing the rate of atherosclerosis progression as compared to placebo.

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We compared bone marrow findings in 2 groups of patients with AIDS during 2 different periods: group 1, n = 20; male/female ratio, 19/1; and group 2, n = 120; male/female ratio, 6/1. Bone marrow iron stores were decreased significantly in group 2 (P < .01), and the incidence of AIDS-related lymphomas was higher, with frequent bone marrow involvement.

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Background: Desferrioxamine (DFO) is an important iron chelating agent. It has also been thought of as an agent with anti-oxidant potential as it chelates ferric iron in various parts of the body. However, there is evidence suggesting that it may paradoxically affect red blood cells (RBC) by inducing intracellular oxidant stress.

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BACKGROUND: Sickle cell anemia is one of the most prevalent hereditary disorders with prominent morbidity and mortality. With this disorder oxidative, phenomena play a significant role in its pathophysiology. One of the garlic (Allium sativum L.

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