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K Nishida

Publications and source records attributed to K Nishida.

At least 37 records · Page 2Linked to original sources
PubMed2001

Human corneal GlcNac 6-O-sulfotransferase and mouse intestinal GlcNac 6-O-sulfotransferase both produce keratan sulfate.

Human corneal N-acetylglucosamine 6-O-sulfotransferase (hCGn6ST) has been identified by the positional candidate approach as the gene responsible for macular corneal dystrophy (MCD). Because of its high homology to carbohydrate sulfotransferases and the presence of mutations of this gene in MCD patients who lack sulfated keratan sulfate in the cornea and serum, hCGn6ST protein is thought to be a sulfotransferase that catalyzes sulfation of GlcNAc in keratan sulfate. In this report, we analyzed the enzymatic activity of hCGn6ST by expressing it in cultured cells. A lysate prepared from HeLa cells transfected with an intact form of hCGn6ST cDNA or culture medium from cells transfected with a secreted form of hCGn6ST cDNA showed an activity of transferring sulfate to C-6 of GlcNAc of synthetic oligosaccharide substrates in vitro. When hCGn6ST was expressed together with human keratan sulfate Gal-6-sulfotransferase (hKSG6ST), HeLa cells produced highly sulfated carbohydrate detected by an anti-keratan sulfate antibody 5D4. These results indicate that hCGn6ST transfers sulfate to C-6 of GlcNAc in keratan sulfate. Amino acid substitutions in hCGn6ST identical to changes resulting from missense mutations found in MCD patients abolished enzymatic activity. Moreover, mouse intestinal GlcNAc 6-O-sulfotransferase had the same activity as hCGn6ST. This observation suggests that mouse intestinal GlcNAc 6-O-sulfotransferase is the orthologue of hCGn6ST and functions as a sulfotransferase to produce keratan sulfate in the cornea.

Amino Acid Sequence↗
PubMed2001

Ocular absorption behavior of palmitoyl tilisolol, an amphiphilic prodrug of tilisolol, for ocular drug delivery.

The objective of this study was to examine the ocular absorption behavior of an amphiphilic prodrug after instillation onto the cornea of rabbits. A micellar solution of O-palmitoyl tilisolol (PalTL), an amphiphilic prodrug, was prepared. After instillation of tilisolol (TL) and PalTL, the drug concentrations in the tear fluid, cornea, aqueous humor, iris-ciliary body, vitreous body, and blood were measured. In addition, in situ ocular absorption behavior was also evaluated. After instillation of TL, the concentration of TL in the tear fluid quickly decreased. After instillation of PalTL, prolonged retention and high concentrations of PalTL in tear fluid and the cornea were observed. In addition, more prolonged retention of the TL concentration after instillation of PalTL than after instillation of TL was observed in the cornea, aqueous humor, and iris-ciliary body. In situ experiments demonstrated that PalTL was mainly absorbed by the corneal route and the improvement effects of PalTL under in vivo conditions was due to an enhanced transit time of PalTL in ocular tissues. PalTL, an amphiphilic prodrug, exhibited increased retention in the precorneal area compared with the parent drug, TL, resulted in improved ocular absorption of the parent drug.

Absorption↗
PubMed2001

An expression profile of active genes in human conjunctival epithelium.

The purpose of this study was to describe the quantitatively and qualitatively genes expressed in in vivo human conjunctival epithelium. A cDNA library was created from human conjunctival epithelial cells obtained from 38 normal eyes by brush cytology. Poly A(+)RNA isolated from these cells was used as a template for cDNA synthesis by the vector-priming method. A 3'-directed cDNA library consisting of the cDNA moiety covering the poly A(+)RNA tail through the nearest Mbo I site was constructed and transformed into Escherichia coli. Inserts in 933 randomly chosen clones were sequenced. The resulting sequences were compared to determine frequency of appearance in the library, and to establish an expression profile of genes in the conjunctival epithelium. The sequences were sent to GenBank for gene identification. The result was an expression profile of active genes reflecting their relative abundance in the conjunctival epithelial mRNA population. The expression profile of human conjunctival epithelium showed that the most abundant gene transcript in human conjunctival epithelium was that for cytokeratin 13. Altogether 102 genes were found to be very active, including beta-2 microglobulin, lipocortin I and insulin-like growth factor binding protein-3. The gene expression profile of the conjunctival epithelium reflects the unique properties and functions of this tissue. Comparison of this expression profile with that obtained from corneal epithelium discloses clear differences and helps us better understand the physiology and pathophysiology of the ocular surface in humans.

Adult↗
PubMed2001

Protective effect of L-arginine against stress-induced gastric mucosal lesions in rats and its relation to nitric oxide-mediated inhibition of neutrophil infiltration.

Pretreatment with l -arginine (150-600 mg kg(-1), i.p.), but not d -arginine (600 mg kg(-1), i.p.), protected against gastric mucosal lesions in rats with water immersion restraint stress over a 6-h period. This protective effect occurred in a dose-dependent manner. Increases in the activities of inducible nitric oxide synthase (iNOS) and myeloperoxidase (MPO), an index of tissue neutrophil infiltration, and the concentration of nitrite/nitrate, breakdown products of nitric oxide, and a decrease in the activity of constitutive nitric oxide synthase (cNOS) occurred in the gastric mucosal tissue with the development of gastric mucosal lesions. The l -arginine pretreatment attenuated the increases in iNOS and MPO activities and nitrite/nitrate concentration and the decrease in cNOS activity in the gastric mucosal tissue in a dose-dependent manner, while the d -arginine pretreatment did not. Both the protective effect of l -arginine (300 mg kg(-1)) against stress-induced gastric mucosal lesions and the attenuating effect of the amino acid on the increases in gastric mucosal iNOS and MPO activities and the decrease in gastric mucosal cNOS activity with the lesion development were counteracted by pretreatment with N(G)-monomethyl- l -arginine (100 mg kg(-1), s.c.), a nitric oxide synthase inhibitor, but not its d -isomer (100 mg kg(-1), s.c.). These results suggest that the protective effect of exogenously administered l -arginine against stress-induced gastric mucosal lesions in rats is, at least in part, due to nitric oxide-mediated inhibition of neutrophil infiltration into the gastric mucosal tissue.

Animals↗
PubMed2001

Agranular CD4+CD56+ blastic natural killer leukemia/lymphoma.

Blastic natural killer cell leukemia/lymphoma (blastic NKL/L) is characterized by blastic morphology and a distinctive immunophenotype combining blastic features and cytologically resembling acute myeloid or lymphoid leukemia. The clinical, pathologic, and cytogenetic features of blastic NKL/L have not yet been systematically identified. We report herein a case of blastic NKL/L with skin lesion, adenopathy, and systemic lymphoadenopathy. The identified tumor cells were positive for CD4 and CD56, and negative for T-cell, B-cell, and myeloid markers. T-cell receptor beta, gamma, delta, and immunoglobulin heavy chain genes in the bone marrow cells showed germ-line configurations. Southern blot analysis with a terminal probe did not reveal any Epstein-Barr virus infection. Although patients diagnosed as blastic NKL/L have generally shown chemotherapy resistance and poor prognosis, our patient was treated with a combined chemotherapy, which is also used for acute lymphoblastic leukemia, and has maintained complete remission (CR) for more than 13 months. In addition to clinical investigations, we thoroughly analyzed his karyotype by using a combination of G-banding and a new technique, spectral karyotyping. The karyotype was described as 45, XY, der(1)t(1;20)(p32;q11.2), der(6) (1pter-->1p32:: 6p21.1-->6q13:: 7q11.2-->7qter), der(7) t(7;20)(q11.2;q11.2), t(13;14)(q14;q32), der(13)t(6;13) (p21.1; q14), -20.

Adult↗
PubMed2001

Transabdominal approach for intrapelvic migration of a total hip prosthesis component.

We report a patient with severe intrapelvic migration of the acetabular component after total hip arthroplasty. Preoperative drip infusion pyelography showed a medial shift in the ureter caused by the migrated acetabular component. Preoperative angiography showed that the right external iliac artery was compressed and shifted medially by the migrated acetabular component. At revision surgery, the migrated acetabular component was successfully removed through a transabdominal (transperitoneal) approach, with the assistance of a general surgeon, and reconstruction was performed through a transtrochanteric approach. We concluded that the transabdominal approach was a useful approach for removing a severely migrated acetabular component.

Female↗
PubMed2001

Factors that influence the surgical effects of astigmatic keratotomy after cataract surgery.

OBJECTIVE: To determine the factors affecting the surgical effect of astigmatic keratotomy (AK) when against-the-rule astigmatism is present following cataract surgery. DESIGN: Prospective interventional noncomparative case series. PARTICIPANTS: Twenty eyes of 19 patients from four medical centers who had against-the-rule astigmatism following cataract surgery. INTERVENTION: AK with a 6 mm optical zone, two linear 3-mm length incisions (T-cut) and a depth of 90% of the central thickness was performed on all subjects. MAIN OUTCOME MEASURES: Vector analysis of astigmatic correction. Multiple regression analysis for seven covariates including age, spherical equivalent of the manifest refraction, preoperative astigmatism, corneal diameter, corneal thickness, mean radius of corneal curvature and axial misalignment. RESULTS: Multiple regression analysis showed that the preoperative astigmatism (p = 0.014) and the axis deviation (p = 0.005) were significantly correlated with the surgical effects. CONCLUSIONS: Even with a uniform surgical procedure, the surgical effects of AK in eyes with against-the-rule astigmatism can be affected by the amount of preoperative astigmatism and the intraoperative axis misalignment. Adding the amount of preoperative astigmatism to the nomogram and improvement of surgical procedures will be required to obtain better surgical predictability of AK following cataract surgery.

Aged↗
PubMed2001

Syntheses, structures, stability, and insulin-like activities of peroxovanadium(V) complexes with a heteroligand.

Several peroxovanadium(V) complexes were prepared with a tripodal or a quasi-tripodal tetradentate ligand. The structures of K(2)[VO(O(2))(nta)].2H(2)O and K[VO(O(2))(DL-cmhist)].H(2)O have been determined by X-ray crystallography (nta, nitrilotriacetate; cmhist, N-carboxymethylhistidinate). The structure of Cs[VO(O(2))(pda)].2H(2)O (pda, N-pyridylmethyliminodiacetate) has been estimated to be similar to that of K[VO(O(2))(DL-cmhist)].H(2)O. Each complex anion in these compounds adopts a distorted pentagonal bipyramidal structure, which is typical for heptacoordinate oxoperoxovanadium(V) complexes. The peroxide ion binds in a side-on fashion to the vanadium(V) center in the pentagonal plane. The peroxide anion in the cmhist complex dissociates rather easily in an acidic solution (pH approximately 3), while that in the other complexes stays intact under similar conditions. The in vitro insulin mimetic effect of the peroxovanadium(V) complexes has been evaluated by the inhibitory effect on free fatty acid (FFA) release in isolated rat adipocytes treated with epinephrine. The cmhist complex is effective, while the others are almost totally ineffective.

Adipocytes↗
PubMed2001

Interphase detection of immunoglobulin heavy chain gene translocations with specific oncogene loci in 173 patients with B-cell lymphoma.

To detect immunoglobulin heavy chain (IGH) gene translocations with specific oncogene loci, we established an interphase cytogenetic approach using double-color fluorescence in situ hybridization (DC-FISH), which we used to analyze 173 patients with B-cell lymphoma. DC-FISH using the IGH gene (14q32.3) in combination with c-MYC (8q24.1), BCL1 (11q13.3), BCL2 (18q21.3), BCL6 (3q27), and PAX-5 (9p13) gene probes detected IGH translocations in 70 (40.5%) of 173 patients. The partner genes involved in IGH translocations were identified in 56 (80%) of 70 patients, and fusion of the IGH gene with specific oncogenes was detected in 53 of 56 patients, particularly in interphase nuclei of 28 patients for whom cytogenetic analysis was not informative. The most common partner gene was BCL2 (19 patients; 27% of IGH translocation-positive patients), followed by BCL6 (16; 23%), BCL1 (11; 16%), c-MYC (7; 10%), and PAX-5 (2; 3%). These oncogenes were closely associated with subtypes of B-cell lymphoma. The other partners were 19q13 (BCL3), 6p25 (MUM1/IRF4), 1q36, and chromosome 8 identified in one patient each. Six of the nine patients with add(14)(q32) showed a BCL6/IGH translocation. Double translocations of the IGH gene were found in three patients; c-MYC+BCL1, c-MYC+BCL2, and c-MYC+BCL6 in each one. Interphase FISH using specific IGH-translocation probes is valuable for defining clinically meaningful subgroups of B-cell lymphoma.

Adolescent↗
PubMed2001

Melting and stone production using MSW incinerated ash.

Most of the municipal solid waste (MSW) in Japan is incinerated and the generated ash is landfilled. However, environmental pollution problems have increased and Japan has decreased final disposal sites for landfills. With the application of a melting system, the volume of incinerated ash can be reduced and the effective use of melted slag is being developed for use in civil engineering works. However, the low strength of melted slag as a vitreous structure has limited its effective use. As a solution for this deficiency, a technology to crystallize melted slag into higher strength produced stones was developed. With the joint cooperation of Chiba Prefecture and Kamagaya City, a demonstration plant for melting and stone production with a capacity of 4.8 tons of incinerator ash per day was constructed. The demonstration test was conducted from May 1998 to June 1999 with satisfactory results stated below. Long-term stable operation and performance of the plant have been confirmed and effective applications of produced stones have been demonstrated on a commercial scale. The results are as follows. 1. A stable, continuous operation and good quality produced stones have been confirmed by treating more than 750 tons of MSW incinerated ash. 2. More than 99.9% of dioxins contained in the incinerated ash were decomposed, and the concentration of dioxins in produced stones were less than the detection limit set by Japanese environmental standards. 3. Leaching values of hazardous heavy metals of produced stones sufficiently met the environmental standard on soil pollution of the Environment Agency with superior leaching behavior for the vitreous slag, thus confirming their safe applications. 4. The effective application of produced stones for aggregate was tested based on Japanese Industrial Standards and every figure of test results met the Japanese standard values. The use of produced stones as raw materials for permeable pavement blocks has been confirmed in commercial construction for a park in Chiba Prefecture. Asphalt use was also demonstrated by paving a commercial roadway in Kamagaya City.

Aluminum Oxide↗
PubMed2001

Characteristics of the human ocular surface epithelium.

An appreciation of the biological characteristics of the human ocular surface epithelium affords us a great insight into the physiology of the human ocular surface in health and disease. Here, we review five important aspects of the human ocular surface epithelium. First, we recognize the discovery of corneal epithelial stem cells, and note how the palisades of Vogt have been suggested as a clinical marker of their presence. Second, we introduce the concept of the gene expression profile of the ocular surface epithelium as arrived at using a new strategy for the systematic analysis of active genes. We also provide a summary of several genes abundantly or uniquely expressed in the human corneal epithelium, namely clusterin, keratin 3, keratin 12, aldehyde dehydrogenase 3 (ALDH3), troponin-I fast-twitch isoform, ssig-h3, cathepsin L2 (cathepsin V), uroplakin Ib, and Ca(2+)-activated chloride channel. Genes related to limbal and conjunctival epithelia are also described. Third, we touch upon the genetic abnormalities thought to be involved with epithelial dysfunction in Meesmann's dystrophy, gelatinous drop-like corneal dystrophy, and the ssig-h3-mutated corneal dystrophies. Fourth, we provide an update regarding the current state of knowledge of the role of cytokines, growth factors and apoptosis in relation to ocular surface homeostasis and tissue reconstruction; the main factors being epidermal growth factor (EGF), keratinocyte growth factor (KGF), hepatocyte growth factor (HGF), transforming growth factor-ss (TGF-ss), and some inflammatory cytokines. Fifth, corneal epithelial barrier function and dysfunction as measured by fluorophotometry is remarked upon, with an explanation of the FL-500 fluorophotometer and its ability to detect corneal epithelial dysfunction at a subclinical level. The research described in this review has undoubtedly generated a complete understanding of corneal epithelial pathophysiology-an understanding that, directly or indirectly, has helped advance the development of new therapeutic modalities for ocular surface reconstruction.

Apoptosis↗
PubMed2001

Immunohistological study of infiltrated cells and cytokines in murine herpetic keratitis.

PURPOSE: To identify localization and kinetics of infiltrated cells and cytokines in murine herpetic keratitis. METHODS: HSV-1 was inoculated onto the scarified BALB/c corneas. At given times post infection (PI), eyes were removed and studied immunohistochemically using monoclonal antibodies against several infiltrated cells and cytokines. RESULTS: Neutrophils and NK cells infiltrated as early as 1 day PI reaching a maximum number at 2 day PI in initial stage. gamma delta TCR positive cells were observed in the corneal stroma from 1 day PI to 8 day PI. IL-2 and IFN-gamma were positive in the cell-infiltrated areas of the epithelial and stromal lesions, whereas IL-4 was negative throughout the experiment. CONCLUSION: Our results indicated that cytokine profile upon herpes infection on the cornea is Th1 dominant. Together with neutrophils in the early phase of infection, gamma delta positive T cells may play an additional role in protecting the cornea against incoming pathogens.

Animals↗
PubMed2001

Uroguanylin level in umbilical cord blood.

BACKGROUND: Uroguanylin is a novel natriuretic and diuretic peptide originally isolated from urine. METHODS: To determine whether uroguanylin has a physiologic role during the perinatal period, uroguanylin levels in umbilical cord plasma obtained at the time of delivery were measured by radioimmunoassay and compared with cord serum osmolality. RESULTS: Mean (+/- SD) cord plasma uroguanylin concentrations (8.8 +/- 2.1 fmol/mL) were higher compared with normal adult values. The extent of maturity, mode of delivery and gender did not appear to influence cord uroguanylin levels. The uroguanylin concentration had a significant positive correlation with cord serum osmolality. CONCLUSION: These findings support some regulatory role of this peptide in perinatal renal and cardiovascular adaptation.

Fetal Blood↗
PubMed2001

Involvement of nitric oxide in chondrocyte cell death in chondro-osteophyte formation.

OBJECTIVE: To examine the nitric oxide (NO) production relevant to chondrocyte cell death in order to elucidate the mechanism of chondro-osteophyte formation in osteoarthrotic joints. DESIGN: Human chondro-osteophytes were obtained during total hip arthroplasty. Expression of inducible nitric oxide synthase (iNOS) mRNA was determined by in-situ hybridization. Localization of iNOS and nitrotyrosine at protein level were examined by immunohistochemistry. Cell death of chondrocytes were confirmed by both TUNEL method and transmission electron microscopy. RESULTS: The various populations of proliferative and hypertrophic chondrocytes expressed iNOS mRNA and iNOS as well as nitrotyrosine protein. Approximately 30% of hypertrophic chondrocytes forming chondro-osteophyte showed positive reaction to TUNEL staining. Electron microscopy confirmed both disintegrated and apoptotic chondrocytes in these zones. In the deep hypertrophic zone calcification was seen around each of the matrix vesicles and some masses of cell debris. CONCLUSION: Chondro-osteophyte formation involves NO production by chondrocytes. The expression and localization of iNOS and nitrotyrosine in chondro-osteophytes suggest the significant role of NO in chondrocyte hypertrophy and apoptosis.

Aged↗
PubMed2001

A variable region on the chlorovirus CVK2 genome contains genes possibly involved in the host range determination.

A 22.6-kbp variable region near the left end of the chlorovirus CVK2 genome which was characterized. This region contained a tandem array of 5 gene copies for Vp260-like protein, a viral surface glycoprotein. The authentic 104-kDa Vp260 was encoded at another site on the genome and contained 13 internally located, tandem repeats of 61-65 amino acids like the prominent Rickettsia surface antigen. By Northern and Western blot analyses, these genes were demonstrated to be expressed late in infection and the proteins were incorporated into virions. These results implied that the extra copies of Vp260-like proteins may be involved in host range in the natural environment.

Gene Dosage↗
PubMed2001

Regulatory mechanism of the gene expression during chlorovirus infection cycle.

In chlorovirus infection, immediate-early gene expression occurs within 5-20 min post infection (p.i.). We identified 16 major immediate-early transcripts. On Northern blot analysis, these transcripts showed unusual behaviors: (I) after 40 min p.i., their sizes reduced by approximately 100 nt, most likely caused by loss of a poly(A) tail and (II) after 40 min p.i., often appeared a few larger additional transcripts that may be formed by read-through from an upstream gene or into a downstream gene. These results indicate that the transcription of the viral genes changes drastically between before and after 40 min p.i.

Chlorella↗
PubMed2001

Reconstruction of the proximal humerus with the clavicle after tumor resection: a case report.

Reconstruction of the proximal humerus after resection for tumor and modification of the clavicular transposition procedure is described in which the blood supply of the clavicle is preserved and the clavicle is used to bridge the defect. An 11-year-old boy presented with shoulder pain, and the diagnosis was osteosarcoma of the right proximal humerus. After resection of the sarcomatous proximal humerus, the clavicle was released with its periosteum remaining intact, and the clavicle was rotated downward around the acromioclavicular joint. A vascularized fibula supplemented the reconstruction in trying to gain length of the arm. The acromioclavicular joint and the vascular supply of the clavicle were preserved. Internal fixation from the clavicle and the fibula to the distal humerus was made with an AO plate and screws. Muscles around the proximal humerus were reattached to the clavicle. Range of motion of the shoulder was 80 degrees flexion, 85 degrees abduction, 30 degrees external rotation, and 90 degrees internal rotation. Although the postoperative followup is relatively short, only 2 years, the functional advantages of this operation over other forms of reconstruction can be observed.

Bone Neoplasms↗