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Biomedical subjects

H Iijima

Publications and source records attributed to H Iijima.

At least 37 records · Page 2Linked to original sources

Cystoid macular edema associated with topical latanoprost in glaucomatous eyes with a normally functioning blood-ocular barrier.

PURPOSE: To study prospectively using optical coherence tomography (OCT) whether topical latanoprost induces retinal disorders, such as cystoid macular edema, in patients with glaucoma and a normally functioning blood-ocular barrier. METHODS: Sixty-eight eyes of 38 patients with glaucoma and no history of intraocular surgery, uveitis, or laser trabeculoplasty were studied. Before initiation of latanoprost treatment and after 1, 3, and 6 months of treatment, OCT images were taken, and the following tests were performed: visual acuity examination, fundus ophthalmoscopy, intraocular pressure measurement, and fundus color photography. To evaluate retinal thickness in the fovea accurately. OCT scanning was repeated six times, and the smallest value was used as the retinal thickness in the fovea. RESULTS: Latanoprost ophthalmic solution did not influence retinal thickness in the fovea at any investigated time points compared with the time before instillation, and no changes were observed in visual acuity, ophthalmoscopic findings, and fundus photographs. The intraocular pressure was reduced significantly at all investigated time points compared with the time before instillation. CONCLUSIONS: It is unlikely that topical latanoprost induces retinal disorders, such as cystoid macular edema, in glaucomatous eyes with a normally functioning blood-ocular barrier.

Adult↗

Iridial pigmentation induced by latanoprost ophthalmic solution in Japanese glaucoma patients.

PURPOSE: To investigate the incidence of iridial pigmentation induced by latanoprost ophthalmic solution in Japanese glaucoma patients by a prospective and observer-masked study. PATIENTS AND METHODS: Sixty-nine eyes of 69 glaucoma patients were included. Patients who had undergone intraocular surgery, laser trabeculoplasty, and laser iridotomy within 12 months before enrollment, and patients with history of uveitis and any changes in antiglaucoma drugs within 6 months before enrollment were excluded. Iridial photographs were taken by one examiner under the same conditions at 1, 3, and 6 months after the initiation of latanoprost treatment. Three glaucoma specialists, masked of patient information, independently assessed the iridial pigmentation. Cases with iridial pigmentation diagnosed by three specialists were categorized as showing a definite increase in iridial pigmentation. RESULTS: A definite increase in iridial pigmentation occurred in 3.5%, 9.7%, and 35.0% of eyes within 1, 3, and 6 months of treatment, respectively. Age, gender, or concomitantly used eyedrops did not significantly influence the incidence of iridial pigmentation within 6 months of instillation. A reduction of intraocular pressure by latanoprost did not differ significantly between patients with and without iridial pigmentation. CONCLUSION: The incidence of iridial pigmentation by latanoprost ophthalmic solution in Japanese patients was higher than previously reported values in pigmented races.

Adult↗

Nitric oxide and protein nitration are eosinophil dependent in allergen-challenged mice.

To explore the possible role of eosinophils in NO-mediated tissue injury, we studied a murine model of allergic asthma. Male A/J mice were sensitized and challenged intranasally with ovalbumin (OVA). Following challenge, the number of eosinophils in bronchoalveolar lavage fluid (BALF) increased from 0.4% of total cells at baseline (0.02 x 10(4) cells/ml) to 60.2% at 48 h after the challenge (9.34 x 10(4) cells/ml). The rise in eosinophil count was accompanied by a 40.3% increase in total NO(2-) plus NO(3-) (NO(x)) in BALF. This in turn was accompanied by expression of inducible NO synthase (NOS II) in airway epithelial and inflammatory cells, as well as by evidence of staining for 3-nitrotyrosine (3NT) in peribronchial inflammatory cells and at the epithelial surface. Both NO(x) production and 3NT were significantly reduced by pretreatment of the challenged mice with the highly specific NOS II inhibitor N-3-aminomethyl-benzyl-acetamidine-dihydrochloride (1400W), as well as by the nonselective NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME). L-NAME and 1400W also reduced the number of BALF eosinophils (37.2% and 61.5%, respectively, as compared with the control value), suggesting that NO production by NOS II contributes to eosinophil recruitment. To further examine the role of eosinophils, we pretreated additional mice with an anti-interleukin (IL)-5 antibody, which reduced BALF eosinophilia following OVA challenge by 90.1%. In concert with the decrease in eosinophils, the anti-IL-5 antibody reduced NO(x) in BALF almost to the baseline value, and decreased the number of 3NT-positive cells in the peribronchial region by 74.4%. Western blot analysis of protein extracted from whole lung confirmed the reduction in tyrosine nitration by anti-IL-5 antibody. These findings indicate that NO and eosinophilic inflammation are closely coupled, and suggest that eosinophils are an important source of tyrosine nitration.

Analysis of Variance↗

Effect of whole-body x-irradiation on antigen-induced airway response in sensitized guinea pigs.

The objectives of this study were to test the hypothesis that x-irradiation inhibits the late asthmatic response (LAR) without influencing the early asthmatic response (EAR) and to examine the mechanism of the inhibitory effect. Twenty sensitized guinea pigs were irradiated at a dose of 8 Gy. The next day, one-half of the animals were injected intravenously with spleen cells (2 x 10(8)) collected from unirradiated sensitized guinea pigs, whilst the other half were injected with vehicle only. Ten additional unirradiated sensitized guinea pigs also received vehicle only. Antigen inhalation challenge took place two days later. Pulmonary resistance was measured for 6 h after antigen exposure, and bronchoalveolar lavage and lung fixation were then undertaken. The area under the percentage pulmonary resistance curve 2-6 h after allergen inhalation was used for analysis of the LAR, while the maximal percentage change in pulmonary resistance was used for analysis of the EAR. Irradiation abolished the LAR (364.4+/-49.4 versus 62.8+/-10.4) without inhibiting the EAR (229.3+/-27.2 versus 278.7+/-40.2) and significantly inhibited the accumulation of eosinophils and lymphocytes in the airways. Transfer of spleen cells restored the LAR (334.4+/-66.8) and the recruitment of cells to the levels seen in unirradiated sensitized guinea pigs. In addition, transfer of only CD4+ T-lymphocytes separated from the spleen cells restored the LAR (439.4+/-62.1) and the cell infiltration into the airways. These inhibitory effects of x-irradiation were due to decreases in numbers of CD4+ T-lymphocytes.

Airway Resistance↗

Double lesions are produced in DNA oligomer by ionizing radiation and by metal-catalyzed H2O2 reactions.

It was demonstrated previously that double lesions are produced in DNA by ionizing radiation. These double lesions consist of adjacent nucleotides each bearing a modified base. The goal of the present investigation was to determine whether Fenton chemistry can generate the same kind of lesions. DNA oligomers were exposed to metal-catalyzed H(2)O(2) reactions, and the products were characterized by chromatography and by mass spectrometry. Double lesions are produced by this treatment in which deoxyguanosine is oxidized to 8-oxo-7,8-dihydrodeoxyguanosine and an adjacent pyrimidine nucleoside is degraded to a formamido remnant.

8-Hydroxy-2'-Deoxyguanosine↗

Basedow's disease and chronic ulcerative colitis: a case report and review of the Japanese literature.

A case of Basedow's disease, that developed after successful treatment of ulcerative colitis with a total colectomy, is presented, along with a review of the Japanese literature on the coexistence of hyperthyroidism and ulcerative colitis. A 26-year-old man was referred to our department, complaining of general fatigue, appetite loss, and palpitation. At age 14, blood was discovered in his stool and a diagnosis of ulcerative colitis was made. Since then, he has been treated with salazosulfapyridine and prednisolone. On examination, mild exophthalmos and thyroid swelling were observed. Both serum free T3 and T4 levels were increased along with a positive TSH receptor antibody, while TSH was decreased. Scintigraphic and ultrasonographic examinations of the thyroid gland showed diffuse enlargement. Treatment with thiamazole relieved the symptoms and normalized the thyroid function. Although a high incidence of autoimmune thyroid diseases in association with ulcerative colitis has been suggested, only 6 cases of hyperthyroidism coexisting with ulcerative colitis have been reported in Japan. A common immunological process has been suggested to be implicated in the pathogenesis of this association, however, the exact mechanism remains unclear.

Adult↗

Spontaneous regression of hepatic adenoma in a patient with glycogen storage disease type I after hemodialysis: ultrasonographic and CT findings.

A 23-year-old woman was admitted to our hospital with recurrent gouty arthritis. Laboratory findings showed hypoglycemia, lactic acidosis, hyperlipidemia, and hyperuricemia, with normal values of serum alfa-fetoprotein (AFP) and protein induced by vitamin K absence (PIVKA-II). A diagnosis of glycogen storage disease type I (GSD-type I) was made on the basis of the laboratory data, liver biopsy findings, and partially deficient thrombocyte glucose-6-phosphatase (G-6-Pase) activity. Ultrasonography and computed tomography revealed multiple focal hepatic masses. Biopsied specimens of the lesion demonstrated a hepatic adenoma, which changed in appearance in the relatively short period between echography and computed tomography. This interesting phenomenon may highlight the importance for careful follow-up of hepatic adenomas, because of the potential of rupture, hemorrhage, or malignant transformation. During follow-up, the present patient received hemodialysis due to renal failure, and the adenoma regressed spontaneously after 8 years. Included are diagnostic images, demonstrating the association of hepatic adenoma and GSD-type I.

Adenoma, Liver Cell↗

[Compounds modulating parathyroid hormone (PTH) secretion].

The control of parathyroid hormone (PTH) secretion is strictly regulated by the parathyroid Ca receptor (CaR). Calcimimetics and calcilytics selectively act on the parathyroid CaR to inhibit and enhance PTH secretion, respectively. According to the recent pharmacological two-state model, calcimimetics act on the CaR as allosteric agonists to stabilize an active conformation of CaR. Conversely, calcilytics act on the CaR as allosteric inverse agonists to stabilize an inactive conformation of CaR. These compounds that can alter circulating levels of PTH and bone turnover might provide novel treatments for adynamic bone disease in patients with chronic renal failure.

English Abstract↗

Alteration of V beta usage and cytokine production of CD4+ TCR beta beta homodimer T cells by elimination of Bacteroides vulgatus prevents colitis in TCR alpha-chain-deficient mice.

A major pathogenic factor for the development of inflammatory bowel disease (IBD) is the breakdown of the intestinal homeostasis between the host immune system and the luminal microenvironment. To assess the potential influence of luminal Ags on the development of IBD, we fed TCR alpha(-/-) mice an elemental diet (ED). ED-fed TCR alpha(-/-) mice showed no pathologic features of IBD, and their aberrant mucosal B cell responses were suppressed. Similar numbers of CD4(+), TCR betabeta homodimer T cells (betabeta T cells) were developed in the colonic mucosa of ED-fed mice; however, Th2-type cytokine productions were lower than those seen in diseased regular diet (RD)-fed mice. The higher cytokine production in diseased RD-fed mice could be attributed to the high incidence of Bacteroides vulgatus (recovered in 80% of these mice), which can induce Th2-type responses of colonic CD4(+), betabeta T cells. In contrast, ED-fed TCR alpha(-/-) mice exhibited a diversification of Vbeta usage of betabetaT cell populations from the dominant Vbeta8 one associated with B. vulgatus in cecal flora to Vbeta6, Vbeta11, and Vbeta14. Rectal administration of disease-free ED-fed mice with B. vulgatus resulted in the development of Th2-type CD4(+), betabeta T cell-induced colitis. These findings suggest that the ED-induced alteration of intestinal microenvironments such as the enteric flora prevented the development of IBD in TCR alpha(-/-) mice via the immunologic quiescence of CD4(+), betabeta T cells.

Administration, Rectal↗

Structural requirements for antigen presentation by mouse CD1.

The structural basis for the T cell response to glycolipid antigens (Ags) remains poorly understood. T lymphocytes autoreactive for mouse CD1 (mCD1.1) or reactive for the glycosphingolipid alphagalactosylceramide (alpha-GalCer) presented by mCD1.1 have been described previously. In this paper it is shown that mutations at the top of the alpha helices and in the bottom of the Ag-binding groove can disrupt both mCD1.1 autoreactivity and alpha-GalCer recognition. The locations of the positions that affect T cell responses indicate that recognition of mCD1.1 is not likely to be unconventional or superantigen-like. Furthermore, the effects of the bottom of the pocket mutation suggest that the autoreactive response could require an autologous ligand, and they indicate that alpha-GalCer binds to the groove of mCD1.1, most likely with the shorter 18-carbon hydrophobic chain in the A' pocket. Natural killer T cell hybridomas with identical T cell antigen receptor (TCR) alpha chains and different beta chains respond differently to alpha-GalCer presented by mCD1.1 mutants. This finding indicates a role for TCR beta in defining natural killer T cell specificity, despite the more restricted diversity of the alpha chains in these cells. Overall, the data are consistent with a mode of lipoglycan recognition similar to that proposed for glycopeptides, in which the TCR alpha and beta chains survey a surface composed of both mCD1.1 and the carbohydrate portion of alpha-GalCer.

Amino Acid Substitution↗

Double-base lesions are produced in DNA by free radicals.

Evidence has been accumulating at the oligomer level that free radical-initiated DNA damage includes lesions in which two adjacent bases are both modified. Prominent examples are lesions in which a pyrimidine base is degraded to a formamido remnant and an adjacent guanine base is oxidized. An assay has been devised to detect double-base lesions based on the fact that the phosphoester bond 3' to a nuclesoside bearing the formamido lesion is resistant to hydrolysis by nuclease P1. The residual modified dinucleoside monophosphates obtained from a nuclease P1 (plus acid phosphatase) digest of DNA can be (32)P-postlabeled using T4 polynucleotide kinase. Using this assay the formamido single lesion and the formamido-8-oxoguanine double lesion were detected in calf thymus DNA after X-irradiation in oxygenated aqueous solution. The lesions were measured in the forms d(P(F)pG) and d(P(F)pG(H)), where P(F) stands for a pyrimidine nucleoside having the base degraded to a formamido remnant and G(H) stands for 8-oxo-deoxyguanosine. The yields in calf thymus DNA irradiated 60 Gy were 8.6 and 3.2 pmol/microgram DNA, respectively.

Adenosine Triphosphate↗

Optical coherence tomography of orange-red subretinal lesions in eyes with idiopathic polypoidal choroidal vasculopathy.

PURPOSE: To study the cross-section images of orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy and compare their protrusions quantitatively with those of serous retinal pigment epithelium detachment. METHODS: Optical coherent tomography images scanning remarkable orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy and serous retinal pigment epithelium detachment in age-related macular degeneration or central serous chorioretinopathy were prospectively recorded. The correlation between the base diameter and the height of the lesions was analyzed. RESULTS: Optical coherence tomography images show prominent anterior protrusion of the orange-red lesions. The ratio of the height to the base diameter of the orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy is 0.32+/-0.05, and it is significantly larger than lesions in eyes with serous retinal pigment epithelium detachment (0.18+/-0.05, P< .001). CONCLUSION: The orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy have a more sharply peaked shape than serous retinal pigment epithelium detachment as a subretinal structure, suggesting polypoidal vascular lesions in eyes with idiopathic polypoidal choroidal vasculopathy are situated beneath the Bruch membrane and covered anteriorly with both the retinal pigment epithelium and the Bruch membrane.

Aged↗

Ultrasound biomicroscopic study of ciliary body thickness in eyes with narrow angles.

PURPOSE: To determine the ciliary body thickness and other biometric findings in eyes with narrow angles. METHODS: Eighteen otherwise normal eyes with narrow angles in 18 Japanese patients and 18 normal control eyes with open angles in 18 age-matched and sex-matched Japanese patients were studied. A-scan ultrasonography was performed to measure anterior chamber depth, lens thickness, axial length, and relative lens position. Ultrasound biomicroscopy was also performed to obtain measurements of the anterior ocular structures, including anterior chamber depth and ciliary body thickness at sites 1 mm and 2 mm posterior to the scleral spur (positions 1 and 2, respectively). RESULTS: Compared with normal control eyes, the narrow-angle eyes showed a shallower anterior chamber (narrow angle, 1.87 +/- 0.27 mm; control, 2.69 +/- 0.26 mm; P <.0001), a thicker lens (4.97 +/- 0.49 mm, 4.26 +/- 0.53 mm; P <.0001), a more anteriorly located lens (2. 21 +/- 0.13, 2.35 +/- 0.14; P <.0001), a shorter axial length (22.70 +/- 0.97 mm, 23.41 +/- 0.86 mm; P =.012), and a thinner ciliary body (position 1: 454 +/- 107 microm, 602 +/- 86 microm; P <.0001; position 2: 203 +/- 50 microm, 321 +/- 68 microm; P <.0001). Lens thickness was significantly correlated with ciliary body thickness at positions 1 (R(2) = 0.34; P =.0001) and 2 (R(2) = 0.43; P <.0001). Anterior chamber depth was significantly correlated with ciliary body thickness at positions 1 (R(2) = 0.48; P <.0001) and 2 (R(2) = 0.56; P <.0001). CONCLUSION: Thinning of the ciliary body may be one of the important factors associated with the anterior location of the lens, the increased lens thickness, and the decreased anterior chamber depth in eyes with a narrow angle.

Acute Disease↗

Investigation of TTV by in situ hybridization in patients with chronic hepatitis.

To clarify whether TT virus (TTV) was present in liver tissues, 12 liver tissue samples from patients with chronic hepatitis positive for TTV in their serum and 11 samples from serum-negative patients were obtained by needle biopsies and investigated using in situ hybridization. Positive staining was observed in nine (75%) of 12 cases positive for TTV (serum-positive group) and three (27.3%) of 11 cases negative for TTV (serum-negative group) (P=0.061). Three kinds of staining patterns were observed: nuclear, cytoplasmic and both. In 58.3% (7/12) of the patients positive for TTV staining, the stained areas were found in both the nucleus and cytoplasm. Only cytoplasmic staining was observed in three cases from the serum-positive group. Only nuclear staining was observed in two cases from the serum-negative group. No significant differences were found in the clinical background between the in situ hybridization-positive and -negative groups, and between the serum-positive and -negative groups. The present study shows that TTV exists in the liver tissue, especially in hepatocytes, of chronic hepatitis patients and that the localization of TTV in the cell is different from case to case, although why this is so remains to be clarified.

Journal Article↗

Cyclo-oxygenase-2 inhibitors suppress epithelial cell kinetics and delay gastric wound healing in rats.

BACKGROUND AND AIMS: The present study examined the effects of NS-398, a specific cyclo-oxygenase-2 inhibitor, on gastric mucosal cell kinetics and gastric wound healing following acid-induced injury. METHODS: Male Sprague-Dawley rats were fasted for 24 h and then 0.6 mol/L hydrochloric acid (HCl; 1 mL) was administered into the stomach; NS-398 or indomethacin was administered to the animals 10 min after the acid. Levels of constitutive cyclo-oxygenase (COX-1) and mitogen-inducible cyclo-oxygenase (COX-2) in the gastric mucosa were analysed using western blotting and immunohistochemical staining. The grade of the lesion was assessed using planimetry and histological examination, including immunohistochemistry for proliferating cell nuclear antigen (PCNA). RESULTS: Although there was strong expression of COX-1, there was minimal expression of COX-2 in the gastric mucosa. Expression of COX-2 was enhanced mainly in surface epithelial cells and neck cells following HCl administration. Gastric mucosal ulcers and erosions healed within 48 h, during which time the proliferative zone expanded in the control animals. Indomethacin and NS-398 suppressed the expansion of the proliferative zone and delayed the healing of the gastric injury. CONCLUSION: The present study demonstrated that cyclo-oxygenase-2 inhibitors delay gastric wound healing by suppressing expansion of the mucosal proliferative zone. These results provide evidence that cyclo-oxygenase-2 has an important role in gastric mucosal regeneration.

Animals↗

Expression of cyclooxygenase-2 and nitrotyrosine in human gastric mucosa before and after Helicobacter pylori eradication.

To determine whether cure of Helicobacter pylori infection influences the expression of COX-2 and nitrotyrosine in the distal stomach of humans, biopsy specimens were examined immunohistochemically. H. pylori infection was determined using a rapid urease test, culture and histology. Positive staining of COX-2/nitrotyrosine in the epithelium was expressed as the percentage of stained cells to the total epithelial cells. There was a significant increase in COX-2/nitrotyrosine staining in H. pylori -positive subjects compared with H. pylori -negative subjects. Cure of the infection resulted in a significant decrease in both COX-2/nitrotyrosine staining in all patients (52.1+/-12.1% vs 15. 4+/-7.2%, P<0.001; and 57.3+/-13.6% vs 36.1+/-18.0%, P<0.01, respectively). However, immunoreactivity of COX-2/nitrotyrosine was observed in all cases with intestinal metaplasia even after the cure of H. pylori infection.Thus, cure of H. pylori infection may decrease the risk of gastric carcinogenesis due to COX-2 and NO-related compounds in gastric mucosa but not in those patients with intestinal metaplasia.

Adult↗