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91.
Keratoconjunctivitis sicca (KCS) is a common complication of graft-versus-host disease (GVHD), and may lead to corneal epithelial defect and melting. In contrast, recurrent corneal calcareous degeneration and perforation is rare. A 46-year-old woman developed chronic GVHD after bone marrow transplantation for aplastic anemia. Severe KCS with corneal melting and calcium deposits were noted in the left eye. Penetrating keratoplasty was performed because of corneal perforation, but poor re-epithelialization and calcium deposition recurred. Lamellar keratectomy and amniotic membrane transplantation (AMT) were performed, but acute calcareous degeneration developed with subsequent recurrence of corneal perforation. After regraft, AMT and tarsorrhaphy, the corneal graft remained clear for 3 months. However, breakdown of the corneal epithelium occurred 3 weeks after spontaneous separation of tarsorrhaphy. Six months later, corneal perforation recurred again along with exacerbation of GVHD. Regraft was performed, but the patient refused tarsorrhaphy and AMT. Poor re-epithelialization persisted after regraft. Corneal melting with impending corneal perforation ensued. Further corneal surgery was refused and the patient chose to undergo evisceration. This case demonstrates that the ocular complications of GVHD may be severe enough to lead to corneal perforation and calcareous degeneration that is recalcitrant to medical and surgical treatment. 相似文献
92.
In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AID) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P〈0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P〈0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P〈0. 05). Whereas interleukin-4, humoral immune cytokine, was not significant (P〉 0. 05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity. 相似文献
93.
Rong-Sen Yang Huei-Shien Chiang Chih-Hsin Tang Chia-Shin Yeh Tur-Fu Huang 《Toxicon》2005,46(4):387-393
Osteosarcoma is a very malignant bone tumor which has a high metastatic potential and usually lead to poor prognosis. The adhesion of tumor cells to the endothelium or extracellular matrix (ECM) is an essential step in the metastatic cascade. We investigated the effect of thrombin on the adhesion activity of the osteosarcoma cell line, ROS 17/2.8. Incubation with the low concentrations of thrombin (0.01-5 U/ml, 5 min to 24 h) elevated the adhesion activity of ROS 17/2.8 to both human umbilical vein endothelial cells (HUVEC) and extracellular matrix, with the peak effect at the concentration of 0.5 U/ml for 30 min at 37 degrees C. The ROS 17/2.8 cells responded to thrombin by a peak effect of increased adhesion to HUVEC (5.5 folds vs. control) and fibronectin (4.8 folds) after thrombin pretreatment (0.5 U/ml, 30 min, 37 degrees C). Pretreatment with monoclonal antibodies against beta3 integrins, including anti-alphavbeta3, 10E5 and 7E3, effectively antagonized the thrombin-enhanced cell adhesion activity, whereas anti-alpha3beta1 and anti-alpha5beta1 did not antagonize the enhanced cell adhesion. Rhodostomin, an Arg-Gly-Asp (RGD)-containing snake venom peptide, and synthetic peptide RGDS also blocked the thrombin-enhanced ROS 17/2.8 cell adhesion. This study demonstrated that thrombin enhanced the cell adhesion of ROS 17/2.8 cells to HUVEC or ECM through an upregulation of beta3 integrins, and rhodostomin was a strong inhibitor on thrombin-enhanced cell adhesion, either to HUVEC or fibronectin substratum. 相似文献
94.
Alphonse G Taghian Rita Abi-Raad Sherif I Assaad Adrian Casty Marek Ancukiewicz Eren Yeh Peryhan Molokhia Khaled Attia Timothy Sullivan Irene Kuter Yves Boucher Simon N Powell 《Journal of clinical oncology》2005,23(9):1951-1961
PURPOSE: It has been hypothesized that tumors with high interstitial fluid pressure (IFP) and/or hypoxia respond poorly to chemotherapy (CT) because of poor drug delivery. Preclinical studies have shown that paclitaxel reduces the IFP and improves the oxygenation (pO(2)) of tumors. Our aim is to evaluate the IFP and pO(2) before and after neoadjuvant CT using sequential paclitaxel and doxorubicin in patients with breast cancer tumors of >/= 3 cm. PATIENTS AND METHODS: Patients were randomly assigned, according to an institutional review board-approved phase II protocol, to receive neoadjuvant sequential CT consisting of either four cycles of dose-dense doxorubicin at 60 mg/m(2) every 2 weeks followed by nine cycles of weekly paclitaxel at 80 mg/m(2) (group 1) or vice versa, with paclitaxel administered before doxorubicin (group 2). Patients were re-evaluated clinically and radiologically. The IFP (wick-in-needle technique) and pO(2) (Eppendorf) were measured in tumors at baseline and after completing the administration of the first and second drug. RESULTS: IFP and pO(2) were measured in 54 patients at baseline and after the first CT. Twenty-nine and 25 patients were randomly assigned to groups 1 and 2, respectively. Paclitaxel, when administered first, decreased the mean IFP by 36% (P = .02) and improved the tumor pO(2) by almost 100% (P = .003). In contrast, doxorubicin did not have a significant effect on either parameter. This difference was independent of the tumor size or response measured by ultrasound. CONCLUSION: Paclitaxel significantly decreased the IFP and increased the pO(2), whereas doxorubicin did not cause any significant changes. Tumor physiology could potentially be used to optimize the sequence of neoadjuvant CT in breast cancer. 相似文献
95.
Kenneth W Yip Joseph D Mocanu P Y Billie Au Gillian T Sleep Dolly Huang Pierre Busson Wen-Chen Yeh Ralph Gilbert Brian O'Sullivan Patrick Gullane Carlo Bastianutto Fei-Fei Liu 《Clinical cancer research》2005,11(22):8131-8144
PURPOSE: A wide variety of tumors depend on the dysregulation of Bcl-2 family proteins for survival. The resulting apoptotic block can often provide a mechanism for resistance to anticancer treatments, such as chemotherapy and radiation. This current study evaluates the efficacy of combining systemically delivered Bcl-2 phosphorothioate antisense (Bcl-2 ASO) and radiation for nasopharyngeal cancer therapy. RESULTS: Antisense uptake was unaffected by 0, 3, or 6 Gy radiation. Radiation decreased the fraction of viable C666-1 cells to 60%, with a further decrease to 40% in combination with Bcl-2 ASO. Despite a modest in vitro effect, Bcl-2 ASO alone caused the regression of established xenograft tumors in mice, extending survival by 15 days in a C666-1 and by 6 days in a C15 model. The survival times for mice treated with both Bcl-2 ASO and radiation increased by 52 days in C666-1 and by 20 days in C15 tumors. This combination resulted in a more-than-additive effect in C666-1 tumors. Less impressive gains observed in C15 tumors might be attributable to higher expression of antiapoptotic Bcl-2 family proteins and limited drug distribution in the tumor. Retreatment of C666-1 tumors with the Bcl-2 ASO-radiation combination, however, was effective, resulting in mice surviving for >80 days relative to untreated controls. CONCLUSIONS: Our results show that the Bcl-2 ASO and radiation combination is a highly potent therapy for nasopharyngeal cancer. Further examination of combination therapy with radiation and other Bcl-2 family-targeted anticancer agents in both preclinical and clinical settings is definitely warranted. 相似文献
96.
Chunbing Zhang Meihong Shen Fengmeng Teng Pengfei Li Feng Gao Juan Tu Linjiao Luo Chih-Kuang Yeh Dong Zhang 《Ultrasound in medicine & biology》2018,44(8):1786-1798
Reactive oxygen species-induced oxidative stress is an important pathophysiological process during cerebral ischemia/reperfusion (I/R) injury. It has been reported that the protective effect of tetramethylpyrazine (TMP) against cerebral I/R injury can be significantly improved by its combination with ultrasound exposure. However, the molecular mechanisms and signaling pathways underlying the synergistic protective effect remain unclear. In the present work, the damage induced by I/R injury was modeled by glutamate-induced toxicity to pheochromocytoma (PC12) cells. The ultrasound-enhanced protective effect of TMP was systemically investigated by measuring variations in cell viability, cell migration and levels of intracellular reactive oxygen species, the oxidative stress-related protein glutathione, apoptosis-related proteins (caspase-8, -9 and -3), as well as expression of related genes (hypoxia-inducible factor-1a, p53, murine double minute2). The results suggest that the ultrasound-enhanced protective effect of TMP against cerebral I/R injury might act via the reactive oxygen species/hypoxia-inducible factor-1a signaling pathway, and an appropriate ultrasound intensity should be selected to achieve an optimal synergistic neuroprotective effect. 相似文献
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100.
Yung-Hao Yang Su-Ling Yeh 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(4):1109-1116
People tend to look toward where a sound occurs; however, the role of spatial congruency between sound and sight in the effect of sound facilitation on visual detection remains controversial. We propose that the role of spatial congruency depends on the reliability of the information provided by the facilitator; if it is relatively unreliable, adding spatially congruent information can help to unify different sensory inputs to compensate for this unreliability. To test this, we examine the influence of sound location on visual detection with a non-temporal task, presumably unfavorable for sound since it is better for temporal resolution, and predict that spatial congruency should matter in this situation. We used the continuous flash suppression paradigm that makes the visual stimuli invisible to keep the relationship of sound and sight opaque. The sound is on the same depth plane as the visual stimulus (the congruent condition) or on a different plane (the incongruent condition). The target was presented to one eye with luminance contrast gradually increased and continuously masked by flashed Mondrian masks presented to the other eye until the target was released from suppression. We found that sound facilitated visual detection (measured by released-from-suppression time) in the spatially congruent condition but not in the spatially incongruent condition. Together with previous findings in the literature, it is suggested that both task type and modality determine the reliability of the information for multisensory integration and thus determine whether spatial congruency is critical. 相似文献