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991.
Hirakata A Inami T Saito M Okada AA Hida T Ishida S Shinoda K Homori M Kawano K Suzuki S 《Nippon Ganka Gakkai zasshi》2004,108(6):359-367
OBJECTIVE: Recent data suggest that the concentration of interleukin-10 (IL-10) is higher than that of interleukin-6 (IL-6) in the vitreous of eyes of patients with non-Hodgkin's lymphoma. In this study, we evaluated the utility of measuring intravitreal IL-10 and IL-6 concentrations in the diagnosis of intraocular lymphoma. METHODS: Specimens of undiluted vitreous were collected at the time of pars plana vitrectomy and IL-10 and IL-6 concentrations were determined. Vitreous specimens were obtained from 5 patients with suspected intraocular lymphoma and 10 patients with uveitis presumed to be unrelated to a neoplasm. RESULTS: In all 5 patients eventually diagnosed with intraocular lymphoma, the vitreous IL-10 concentration ranged from 3,040 to 11,200 pg/ml, and was higher than the vitreous IL-6 concentration in all cases. In 9 of the 10 patients with uveitis, the vitreous IL-10 concentrations ranged from less than 2 to 97 pg/ml, with an IL-10/IL-6 ratio of less than 0.11. However, in the remaining case diagnosed as uveitis of unknown etiology, the vitreous IL-10/IL-6 ratio was greater than 1. CONCLUSION: Our data suggest that the measurement of vitreous IL-10 concentrations would aid in the diagnosis of intraocular lymphoma. 相似文献
992.
Nontypeable Haemophilus influenzae (NTHi) is one of the leading pathogens in sinusitis. One of the outer membrane proteins of NTHi, P6, is a common antigen to all strains and is an attractive candidate for a subunit bacterial vaccine. In this study, we characterized normal sinus mucosa (SM) and investigated the potential of intranasal immunization with P6 and cholera toxin (CT) for induction of mucosal protective immunity against NTHi in the maxillary sinuses of rats. Intranasal immunization induced P6-specific sinus mucosal and systemic immunological responses, mainly of the IgA and IgG isotype. The protective effect of intranasal immunization was demonstrated by enhancement of sinus clearance of NTHi. The present study showed that unilateral intranasal immunization has a capacity to induce protective immunity against NTHi in the bilateral maxillary sinuses. Systemic administration of the vaccine did not affect sinus clearance of NTHi. These findings suggest that a nasal vaccine might be useful for preventing sinusitis. 相似文献
993.
Morimura K Romanenko A Min W Salim EI Kinoshita A Wanibuchi H Vozianov A Fukushima S 《Oncology reports》2004,11(4):881-886
After the Chernobyl accident in 1986, the incidence of urinary bladder cancers in the Ukraine increased gradually from 26.2 to 43.3 per 100,000 people between 1986 and 2001. In the areas of low level but persistent cesium-137 (137Cs) radio-contamination, a unique atypical radiation-related urinary bladder cystitis named 'Chernobyl cystitis', a possible pre-neoplastic condition in humans, has been detected. We have previously documented high incidences of bladder lesions, including severe dysplasias and/or carcinoma in situ, in association with this cystitis and correlating with oxidative DNA damage. To further investigate the molecular mechanisms underlying bladder carcinogenesis with this specific etiology, mutation analysis of p53 gene (exon 5-8) was performed for 11 and 18 paraffin-embedded bladder cancers in Ukrainians, respectively collected before and after the Chernobyl disaster. DNAs were extracted and subjected to nested PCR-single-strand conformational polymorphism analysis followed by direct DNA sequencing, as well as p53 immunohistochemistry (IHC). The incidences of p53 gene mutation were 54.5 and 16.7% for before and after the Chernobyl disaster, respectively, the difference being statistically significant. Also a tendency for higher p53 IHC score was apparent in the earlier group of lesions. No significant difference was noted for the proportions of historical types. These results point to possible distinct molecular carcinogenic pathways of bladder cancer formation, before and after the Chernobyl disaster, on the basis of variation in p53 gene alteration. 相似文献
994.
995.
Ogihara T Hirano K Ogihara H Misaki K Hiroi M Morinobu T Kim HS Ogawa S Ban R Hasegawa M Tamai H 《Pediatric research》2003,53(4):594-599
Among various hypothetical mechanisms for the in vivo production of reactive oxygen species, transition metal-catalyzed reactions in cooperation with a biologic reducing agent like ascorbic acid or superoxide may be some of the most important. In the present study, we retrospectively examined the existence of non-protein-bound metal ions, an essentially hazardous pro-oxidant form of various transition metals, and the occurrence of metal-catalyzed reactive oxygen species production in cerebrospinal fluid (CSF) of 10 infants with hypoxic ischemic encephalopathy (HIE) subsequent to perinatal asphyxia and 12 control infants within 72 h of birth. Non-protein-bound iron was detected in eight out of 10 CSF samples from the HIE infants and its level was significantly correlated with Sarnat's clinical stage, whereas none of the control infants had detectable non-protein-bound iron levels. Non-protein-bound copper was below the detection limit in all CSF samples from both groups. Ascorbic acid was significantly increased in the CSF of HIE infants when compared with that of controls (means, 664.9 versus 449.4 microM, p = 0.008). ortho-Tyrosine and meta-tyrosine, which are highly specific and sensitive markers of protein oxidation induced by hydroxyl radicals, were significantly higher in HIE infants than in controls when evaluated by the ratio relative to their source amino acid, phenylalanine [means, 110.5 versus 75.4, p = 0.018 for ortho-tyrosine/phenylalanine; 104.6 versus 67.7 (nM/microM x 10(2)), p = 0.048 for meta-tyrosine/phenylalanine]. Both ratios were significantly correlated with non-protein-bound iron, but not with ascorbic acid. Our preliminary observations provide direct evidence that hydroxyl radicals are generated in the CNS during asphyxiation. Iron chelation therapy could be worth developing as a neuroprotective strategy for perinatal asphyxia. 相似文献
996.
Whole-blood manganese levels and brain manganese accumulation in children receiving long-term home parenteral nutrition 总被引:2,自引:0,他引:2
Iinuma Y Kubota M Uchiyama M Yagi M Kanada S Yamazaki S Murata H Okamoto K Suzuki M Nitta K 《Pediatric surgery international》2003,19(4):268-272
Recent reports attribute neurological and cerebral disorders to the accumulation of manganese (Mn) in the brain in patients receiving home parenteral nutrition (HPN). It is desirable to control the amount of Mn delivered to these patients, but a suitable method for monitoring an individual's Mn status and assessing Mn accumulation remains debatable. The aim of this study was to evaluate whether whole-blood manganese levels (WB-Mn) correlate with the accumulation of Mn in the brains of children who receive long-term HPN, using magnetic resonance imaging (MRI) of the brain. Six patients who had received HPN (duration of HPN, 18-137 months) were included in this study. The daily parenteral doses of Mn were calculated while on HPN. WB-Mn was measured and T1-weighted MRI of the brain was obtained for each patient with a 1.5-T MR imager. Twelve months after the withdrawal of Mn from HPN, measurements of WB-Mn and brain MRI were repeated in all patients except for one who was lost after initial examination. The same examinations were performed on an additional patient who had been successfully weaned off a 179 month course of HPN 20 months prior to the initial examination. The parenteral dose of Mn while receiving HPN ranged from 15.7 to 91.5 micro g/kg/day. Initially, MRI showed hyperintensity in the globus pallidus in all patients and in the anterior pituitary in one patient. WB-Mn was elevated in four patients, but was in the normal range in the remaining three. Following subsequent measurements 12 months later, WB-Mn was normal in all patients and MRI hyperintensity remained in the globus pallidus in one patient. One patient was lost after the initial examinations. WB-Mn does not necessarily correlate with the accumulation of Mn in the brain. Periodic MRI should be performed in patients receiving long-term NPN to monitor for excessive Mn accumulation in the brain. 相似文献
997.
998.
Mizuguchi M 《Congenital anomalies》2003,43(1):22-28
ABSTRACT Molecular pathogenesis of human cerebral malformations is briefly reviewed from a neuro-pathologic viewpoint, with emphasis on holoprosencephaly and neuronal migration disorders. Immunopathologic approaches are useful in elucidating the essential pathomechanism of these anomalies. In alobar holoprosencephaly, for instance, immunostaining for glial fibrillary acidic protein clarifies the pathologic significance of the leptomeningeal glioneuronal heterotopia along the ventral prosencephalic surface. In type 1 lissencephaly and subcortical laminar heterotopia, immunohistochemistry for the causative gene products revealed the temporal and spatial pattern of their localization in the normally developing cerebrum, as well as their reduction in these disorders. 相似文献
999.
Yamamoto Y Okamoto T Goto M Yokomise H Yamamoto M Tabata Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(5):533-536
We manufactured an artificial trachea that slowly releases bone morphogenetic protein 2 (BMP-2) and used it to replace a section of the canine trachea. We made a three-layered prosthesis composed of an outer layer of gelatin sponge, a middle layer of collagen sponge, and an inner silicone tube. BMP-2 solution was soaked into the gelatin sponge layer. An approximately 3 cm length of the canine trachea was resected, and the artificial trachea was inserted into the resulting gap and anastomosed. The implanted portion was covered by periosteum. At 2, 4, and 8 weeks after surgery, the inner silicone tube was removed. Soon after removal of the silicone tube at 2 and 4 weeks, the dogs died of choking because of collapse of the trachea. One dog whose silicone tube was removed at 8 weeks was able to survive without choking. At 6 months after removal of the silicone tube, the bronchoscopic findings revealed that the gap in the trachea had been closed by regenerated tissue and covered by mucosa. We have demonstrated that our artificial trachea slowly releasing BMP-2 requires at least 8 weeks to achieve regeneration of solid tissue to support the tracheal gap. 相似文献
1000.
Kato D Takeuchi M Sakurai T Furukawa S Mizokami H Sakata M Hirayama C Kunitake M 《Biomaterials》2003,24(23):4253-4264
A variety of neutral and cationic polymers based on polyamino acids were prepared and investigated as microcarriers for cell attachment and growth. Among neutral polymer particles including the alkylated poly(gamma-methyl L-glutamate) (PG) particles, in which the hydrophobicity changes as a function of the length of the alkyl groups, and hydroxy terminal PG particles, the PG particle with the longest alkyl chain (PG-C12) demonstrated the highest cell attachment rate and highest rate of cell growth. Moreover, the introduction of hydroxyl groups (PG-OH) led to a deterioration of cell growth. Cell growth on cationic particles having primary amino groups was drastically dependent upon the anion exchange capacity (AEC). A higher AEC for aminated PG microcarriers inhibited cell growth. In contrast, a higher AEC for cross-linked poly( epsilon -lysine) (PL) microcarriers facilitated cell growth. Cell growth on cationic particles clearly showed a good correlation with the pK(a,app) of the microcarriers, but not with their AEC. The particles with low and high pK(a) values possessed toxically acidic and basic pH microenvironments near the surface, respectively. These microenvironments had cytotoxic effects. On the other hand, no correlation between attachment rate constants and high cell growth was observed. The aminated particles, in which pK(a) were controlled at neutral pH, and PG-C12 produced obviously higher cell growth than did a commercially available microcarrier. 相似文献