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21.
Histopathological characterisation of effects of the mouse Pax6 missense mutation on eye development
Thaya Ramaesh Steven E. Williams Catriona Paul Kanna Ramaesh John D. West 《Experimental eye research》2009,89(2):263-273
Mutations in PAX6/Pax6 lead to a variety of ocular anomalies in humans and mice. The aim of the study was to characterise the ocular abnormalities caused by the missense Pax6Leca4 mutation and compare them to published observations on Pax6 alleles that are functionally equivalent to Pax6− null alleles (such as Pax6Sey and Pax6Sey-Neu) and human inherited eye diseases. Ocular features of homozygous Pax6Leca4/Leca4 and heterozygous Pax6Leca4/+ embryos at E12.5-E18.5, heterozygous Pax6Leca4/+ young mice at P18 and heterozygous Pax6Leca4/+ adults at 12 weeks were analysed histologically with their wild-type Pax6+/+ littermates. Homozygous Pax6Leca4/Leca4 fetuses died perinatally with no eyes although an optic cup rudiment with pigmented cells developed. Pax6Leca4/+ mice were microphthalmic and a range of other severe ocular phenotypes affected both the anterior and the posterior segments. In contrast to Pax6+/−, the Pax6Leca4/+ eyes had no goblet cells in the corneal epithelium, the iris was not hypoplastic and there was no lens-corneal epithelial plug. However, microphthalmia was more severe, corneal vascularisation occurred earlier (during fetal stages), pigmented cells were present in the vitreous and corneal stroma and the ciliary body was malformed or abnormal. These results show that, although Pax6Leca4/+ lacked some eye abnormalities commonly seen in Pax6Sey/+ and Pax6Sey-Neu/+ eyes, in most respects their eyes were more severely affected. These differences probably reflect both differences between the Pax6Leca4 and the Pax6Sey-Neu mutations and differences in modifier gene expression in different genetic backgrounds. The presence of pigmented cells in the cornea is a novel observation. Some Pax6Leca4/+ ocular abnormalities were similar to those present in human Peters' anomaly and persistent hyperplastic primary vitreous (PHPV) so Pax6Leca4/+ mice provide a useful model for some inherited eye diseases. 相似文献
22.
对我国目前麻风防治策略的思考 总被引:1,自引:0,他引:1
沈建平 《中华流行病学杂志》2009,30(10):1084-1086
1949-2008年我国累计登记麻风患者48万余例,主要分布在北纬38°以南的东南沿海和长江流域省份.新中国成立后,经过积极防治,至20世纪80年代初,以氨苯砜单疗治愈的患者达31万余例;1986年在全国普遍推广WHO联合化疗方案,至2008年底全国累计接受联合化疗的麻风患者近8万例. 相似文献
23.
Robert M. Levy Roman Saikovsky Evgeniya Shmidt Alexander Khokhlov Bruce P. Burnett 《Nutrition Research》2009
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups. 相似文献
24.
25.
目的 探讨 IL - 4和 IL - 10在诱导异种骨移植免疫耐受中的作用。方法 反应细胞为 BAL B/c小鼠脾淋巴细胞 ,刺激细胞为新西兰白兔血淋巴细胞 ,刺激抗原为兔骨上清液。采用经典的混合淋巴细胞培养法及骨上清液与淋巴细胞混合培养法作为异种骨移植的体外实验模型。在各培养液中分别加入 IL - 4、IL - 10及两者联合应用 ,通过测定其 3H- Td R掺入率 ,观察不同细胞因子对刺激淋巴细胞增殖的影响。结果 无论在细胞刺激组还是骨上清液刺激组 ,IL- 4对淋巴细胞增殖均有显著抑制作用 (P<0 .0 0 1和 P<0 .0 5 ) ,IL- 10未表现出抑制作用 (P>0 .0 5 )。在两组 IL- 4和 IL - 10联合应用均产生比 IL - 4单独应用更为明显的细胞增殖抑制作用 (P<0 .0 0 1和 P<0 .0 5 )。结论 IL - 4对由细胞或骨上清液刺激产生的淋巴细胞增殖均有很好的抑制作用 ,IL- 10没有表现出抑制作用 ;IL- 4与 IL- 10联合应用有协同抑制作用。 相似文献
26.
A. B. Soares P. R. Faria L. A. Magna M. E. P. Correa C. A. de Sousa O. P. Almeida M. L. Cintra 《Journal of oral pathology & medicine》2005,34(6):368-373
BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease. 相似文献
27.
性别差异对脓毒症大鼠肝脏Toll样受体4和髓样分化蛋白-2基因表达的影响 总被引:2,自引:0,他引:2
目的探讨性别差异对脓毒症大鼠肝脏组织Toll样受体4(TLR4)和髓样分化蛋白- 2(MD-2)基因表达的影响。方法以脂多糖(LPS)按5 mg/kg体重由大鼠腹腔注射制作脓毒症动物模型,注射后2 h留取肝脏组织检测TLR4、MD-2和肿瘤坏死因子-α(TNF-α)基因表达,同时测定各组大鼠血浆中丙氨酸氨基转移酶(ALT)及雌二醇含量。结果正常雌雄性大鼠肝脏组织均可表达少量TLR4、MD-2、TNF-α基因,其中雌性组分别为0.175±0.034、0.211±0.044、0.201±0.068; 雄性组分别为0.205±0.061、0.243±0.049、0.243±0.063,两组数据差异无统计学意义(P> 0.05),但LPS刺激后雌性大鼠肝脏组织上述指标分别为0.615±0.089、0.708±0.181、0.730± 0.118,血浆中ALT含量为(81.07±10.72)U/L;雄性组分别为0.723±0.091、1.123±0.272、 0.881±0.156,ALT含量为(106.39±14.21)U/L,雌性组各项指标均明显低于雄性大鼠(P< 0.05)。相关分析表明雌性及雄性脓毒症大鼠肝脏组织TLR4及TNF-α基因表达与相应性别大鼠血浆中雌二醇含量呈显著负相关(P<0.05)。结论 LPS刺激后大鼠肝脏组织TLR4、MD-2及 TNF-α基因表达存在性别差异,内源性雌激素的作用可能导致雌性脓毒症大鼠肝脏组织损伤较雄性轻。 相似文献
28.
Hui-Ju Wen Ying-Chu Lin Yung-Ling Lee Yueliang Leon Guo 《Pediatric allergy and immunology》2006,17(7):489-494
High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha. 相似文献
29.
Keishi Kashibuchi Kyoichi Tomita Jack A Schalken Haruki Kume Takumi Takeuchi Tadaichi Kitamura 《International journal of urology》2007,14(9):789-794
OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer. 相似文献
30.
Masafumi Kumano Hideaki Miyake Isao Hara Junya Furukawa Atsushi Takenaka Masato Fujisawa 《International journal of urology》2007,14(4):336-338
BACKGROUND: The objective of this study was to evaluate the efficacy and safety of first-line high-dose chemotherapy (HDCT) combined with peripheral blood stem cell transplantation (PBSCT) for patients with advanced extragonadal germ cell tumors (EGGCT). METHODS: Six male patients with advanced non-seminomatous EGGCT were treated with HDCT combined with PBSCT following 2-3 cycles of conventional-dose induction chemotherapy. The regimens used for HDCT were carboplatin, etoposide and ifosfamide (ICE) in five patients and ICE plus paclitaxel (T-ICE) in one patient, and that for induction therapy was cisplatin, etoposide and bleomycin (PEB) in all patients. As a rule, HDCT was continuously administered until alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin normalized (beta-HCG). RESULTS: Following 1-6 courses of HDCT (median, 4 courses), beta-HCG and AFP were normalized in all patients, and five and one patient were diagnosed as showing partial remission and stable disease, respectively. Five patients underwent surgical resection of residual tumors after HDCT, yielding necrotic tissue in two, mature teratoma in two, and viable cancer tissue in one, and the surgical margin was negative in all patients. At a median follow-up of 36 months, five patients were alive and disease-free, whereas the remaining one died of disease progression. Although all patients had grade 3 hematological toxicity, there was no treatment-related death by combining PBSCT. CONCLUSIONS: First-line HDCT with PBSCT could be safely administered to patients with advanced EGGCT, and the antitumor effect of this treatment was comparatively favorable. First-line HDCT therefore may represent an attractive option for patients with advanced EGGCT. 相似文献