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971.
972.
Juhua Chang Shaoying Liu Shengli Zhou Minghua Wang Guonian Zhu 《Experimental and toxicologic pathology》2013,65(1-2):205-209
Butachlor, a chloracetamide herbicide, is widely used in China. In the present study, paired adult male and female zebrafish (Danio rerio) were exposed to various concentrations of butachlor (0, 25, 50 and 100 μg/L) for 30 days, and the effects on reproduction and endocrine disruption were evaluated using fecundity, condition factor (CF), gonadosomatic index (GSI), liver somatic index (LSI), plasma vitellogenin (VTG), sex steroids and thyroid hormone levels as endpoints. Our results showed that the mean fecundity rates were significantly decreased at 50 and 100 μg/L butachlor during the 30-day exposure period. At the end of the exposure period, no significant changes were observed in CF and LSI in both females and males, while GSI was significantly reduced in males at 50 and 100 μg/L butachlor. At 100 μg/L butachlor, plasma testosterone (T) and 17β-estradiol (E2) levels were significantly decreased in females, while plasma VTG level was significantly increased in males. Plasma thyroxine (T4) and triiodothyronine (T3) levels were significantly increased at 50 and 100 μg/L butachlor in males, and at 100 μg/L in females. This work demonstrated that butachlor adversely affected the normal reproductive success of zebrafish, and disrupted the thyroid and sex steroid endocrine systems, which provides the basis for the estimated ecological risk during butachlor exposure. 相似文献
973.
974.
Weiwei Yan Muhammad Hassan Saleem Patrick McDonough Sean P. McDonough Thomas J. Divers Yung-Fu Chang 《Clinical and Vaccine Immunology : CVI》2013,20(8):1143-1149
Leptospira immunoglobulin (Ig)-like (Lig) proteins are a novel family of surface-associated proteins in which the N-terminal 630 amino acids are conserved. In this study, we truncated the LigA conserved region into 7 fragments comprising the 1st to 3rd (LigACon1-3), 4th to 7.5th (LigACon4-7.5), 4th (LigACon4), 4.5th to 5.5th (LigACon4.5–5.5), 5.5th to 6.5th (LigACon5.5–6.5), 4th to 5th (LigACon4-5), and 6th to 7.5th (LigACon6-7.5) repeat domains. All 7 recombinant Lig proteins were screened using a slot-shaped dot blot assay for the diagnosis of equine leptospirosis. Our results showed that LigACon4-7.5 is the best candidate diagnostic antigen in a slot-shaped dot blot assay. LigACon4-7.5 was further evaluated as an indirect enzyme-linked immunosorbent assay (ELISA) antigen for the detection of Leptospira antibodies in equine sera. This assay was evaluated with equine sera (n = 60) that were microscopic agglutination test (MAT) negative and sera (n = 220) that were MAT positive to the 5 serovars that most commonly cause equine leptospirosis. The indirect ELISA results showed that at a single serum dilution of 1:250, the sensitivity and specificity of ELISA were 80.0% and 87.2%, respectively, compared to those of MAT. In conclusion, an indirect ELISA was developed utilizing a recombinant LigA fragment comprising the 4th to 7.5th repeat domain (LigACon4-7.5) as a diagnostic antigen for equine leptospirosis. This ELISA was found to be sensitive and specific, and it yielded results that concurred with those of the standard MAT. 相似文献
975.
Jeon‐Hor Chen Wei‐Fan Pan Julian Kao Jocelyn Lu Li‐Kuang Chen Chih‐Chen Kuo Chih‐Kai Chang Wen‐Pin Chen Christine E. McLaren Shadfar Bahri Rita S. Mehta Min‐Ying Su 《NMR in biomedicine》2013,26(12):1705-1713
The aim of this study was to evaluate the change of breast density in the normal breast of patients receiving neoadjuvant chemotherapy (NAC). Forty‐four breast cancer patients were studied. MRI acquisition was performed before treatment (baseline), and 4 and 12 weeks after treatment. A computer‐algorithm‐based program was used to segment breast tissue and calculate breast volume (BV), fibroglandular tissue volume (FV), and percent density (PD) (the ratio of FV over BV × 100%). The reduction of FV and PD after treatment was compared with baseline using paired t‐tests with a Bonferroni–Holm correction. The association of density reduction with age was analyzed. FV and PD after NAC showed significant decreases compared with the baseline. FV was 110.0 ml (67.2, 189.8) (geometric mean (interquartile range)) at baseline, 104.3 ml (66.6, 164.4) after 4 weeks (p < 0.0001), and 94.7 ml (60.2, 144.4) after 12 weeks (comparison with baseline, p < 0.0001; comparison with 4 weeks, p = 0.016). PD was 11.2% (6.4, 22.4) at baseline, 10.6% (6.6, 20.3) after 4 weeks (p < 0.0001), and 9.7% (6.2, 17.9) after 12 weeks (comparison with baseline, p = 0.0001; comparison with 4 weeks, p = 0.018). Younger patients tended to show a higher density reduction, but overall correlation with age was only moderate (r = 0.28 for FV, p = 0.07, and r = 0.52 for PD, p = 0.0003). Our study showed that breast density measured from MR images acquired at 3T MR can be accurately quantified using a robust computer‐aided algorithm based on non‐parametric non‐uniformity normalization (N3) and an adaptive fuzzy C‐means algorithm. Similar to doxorubicin and cyclophosphamide regimens, the taxane‐based NAC regimen also caused density atrophy in the normal breast and showed reduction in FV and PD. The effect of breast density reduction was age related and duration related. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
976.
Hong‐Tao Xu Xue‐Mei Xie Qing‐Chang Li Shu‐Li Liu Shun‐Dong Dai Yang Liu En‐Hua Wang 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(2):111-119
Atonal homolog 1 (Atoh1) is crucial to the differentiation of many cell types and participates in tumorigenesis and progression. This study investigated the role of Atoh1 in lung cancer development and its correlation with key members of the Wnt pathway. We used immunohistochemistry to examine the expressions of Atoh1, β‐catenin, Axin, chibby, and Disabled‐2 (Dab2) in 118 samples of lung cancer. We also detected the cytoplasmic and nuclear expression of Atoh1 in lung cancer tissues using western blot. Atoh1 nuclear expression was negatively correlated with differentiation level (p = 0.004) and primary tumor stage (p = 0.044) of lung cancer. Nuclear Atoh1 expression was positively correlated with nuclear expression of chibby (p < 0.001) and Dab2 (p < 0.001). Cytoplasmic Atoh1 expression was positively correlated with the cytoplasmic expression of Axin (p = 0.028), chibby (p < 0.001), and Dab2 (p < 0.001). We conclude that the nuclear expression of Atoh1 was inversely correlated with the differentiation and primary tumor stage of lung cancers. The expression and localization of Atoh1 correlated with Axin, chibby, or Dab2. Atoh1 may be a potential therapeutic target for the inhibition of growth and progression of lung cancers. 相似文献
977.
Cell death and inflammation are the fundamental biological processes in both normal physiology and pathology. Apoptosis is the most well-studied process of cell death, but there are also many other forms of cell death such as necrosis, autophagy and pyroptosis. Cell death could be observed throughout atherosclerosis and plays an important role in determining the fate of atherosclerotic lesion. Inflammation, the primary response of innate immunity, is considered essential in initiating and driving atherosclerosis. Apoptosis and autophagy had been reported in atherosclerosis, however, the mechanism of cell death involved in atherosclerosis still remain largely unknown. Cell death and inflammation are inextricably linked with their effectors modulating the process of atherosclerosis. Therefore, we proposed hypothesis that pyroptosis, an inflammatory form of cell death, may be implicated in atherosclerosis and play an important role in lesion instability. 相似文献
978.
Janoi Chang Yohanna Serrano Raine GarridoLaura M. Rodríguez Jessy PedrosoFelix Cardoso Yury ValdésDagmar García Violeta Fernández-SantanaVicente Verez-Bencomo 《Vaccine》2012
Capsular polysaccharides are important virulence factors of Streptococcus pneumoniae. The polysaccharide has been used as a component of vaccines against pneumococcal diseases either as plain polysaccharide or better conjugated to a protein. The last one is the vaccine of choice to target child protection. The immune responses depend on several polysaccharide physicochemical properties that can be affected during either purification or modification in the case of conjugate vaccines. In serotype 18C, the repeating unit has a complex structure having a branched pentasaccharide with two apparently labile subtituents: glycerol-phosphate and O-acetyl group. The loss of these groups may potentially reduce the ability of the 18C polysaccharide to induce the desired immune response. Therefore, the relationship of both groups with the antigenicity and immunogenicity of 18C capsular polysaccharide is explored. It is shown that glycerol-phosphate must be preserved for conserving adequate antigenicity of the 18C capsular polysaccharide. At the same time, it was proved that O-acetyl groups do not play any role for the antigenicity and immunogenicity. 相似文献
979.
980.