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51.
Amukotuwa S Choong PF Smith PJ Powell GJ Slavin J Schlicht SM 《International Seminars in Surgical Oncology : ISSO》2005,2(1):10
BACKGROUND: Extrapulmonary tuberculosis is one of the great mimickers of medicine, and often masquerades as malignancy. As a result, patients may be referred to oncologists and surgeons for further evaluation and management, delaying the institution of appropriate anti-tuberculous drug therapy. CASE PRESENTATION: We present the case of a 21 year old man with tuberculous osteomyelitis, who was referred to the Bone and Soft Tissue Sarcoma Service at our institution with a provisional diagnosis of malignancy. Further investigation revealed extensive retroperitoneal abdominal and pelvic lymphadenopathy. The recognition of certain patterns on imaging, and finally the isolation of Mycobacterium tuberculosis from tissue samples obtained under image guidance, enabled the correct diagnosis to be made. CONCLUSION: This case highlights the importance of remaining cognisant of the protean manifestations of extrapulmonary tuberculosis, and illustrates the advantage of a clinically directed multi-modality imaging approach to diagnosis. 相似文献
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Jin Young Chung Jung Hoon Choi Choong Hyun Lee Ki-Yeon Yoo Moo-Ho Won Dae Young Yoo Dae Won Kim Soo Young Choi Hwa Young Youn Seung Myung Moon In Koo Hwang 《Neurochemical research》2010,35(4):620-627
Microglia are main form of active immune defense, and they are constantly moving and analyzing the CNS for damaged neurons and infectious agents. In this study, we compared microglia in the spinal cord of the young adult (1–2 years old) and aged (10–12 years old) German Shepherd dogs via immunohistochemistry and western blot analysis for ionized calcium-binding adapter molecule 1 (Iba-1), a microglial marker. In addition, we also observed the interferon-γ (IFN-γ), a pro-inflammatory cytokine, and interleukin-1β (IL-1β), produced by activated microglia/macrophage, protein levels in these groups. At first, we found that neuronal nuclei (NeuN, a neuronal marker)-immunoreactive neurons were distributed throughout the grey mate of the spinal cord, and there were no significant differences between the adult and aged groups. Most of Iba-1-immunoreactive microglia were morphologically ramified microglia (resting form) in the adult group, while some Iba-1-immunoreactive microglia were morphologically activated microglia in the aged group. In western blot analysis, Iba-1, IFN-γ and IL-1β expression were increased in the aged group. This result may be associated with age-dependent changes in the spinal cord. 相似文献
55.
Jung Hoon Choi Ki-Yeon Yoo Choong Hyun Lee Ok Kyu Park Bing Chun Yan Hua Li In Koo Hwang Jeong Ho Park Sung Koo Kim Moo-Ho Won 《Neurochemical research》2010,35(10):1599-1608
In the present study, we investigated age-related differences in neuronal progenitors in the gerbil main olfactory bulb (MOB)
using doublecortin (DCX), a marker for neuronal progenitors which differentiate into neurons in the brain. No difference in
the number of neuronal nuclei (NeuN)-immunoreactive neurons was found in the MOB at variously aged gerbils. At postnatal month
(PM) 1, DCX immunoreaction was detected in all layers of the MOB except for the olfactory nerve layer. At this time point,
DCX-immunoreactive cells (neuronal progenitors) were very abundant; however, they did not have fully developed-processes.
From PM 3, the number of DCX-immunoreactive neuronal progenitors was decreased with age. At PM 6, DCX-immunoreactive cells
showed very well-developed processes. In western blot analysis, DCX protein level in the MOB was highest at PM 1. Thereafter,
levels of DCX protein were decreased with age. In the subventricular zone of the lateral ventricle, the number of Ki-67-immunoractive
cells (proliferating cells) was also significantly decreased with age. In addition, increases of α-synuclein-immunoreactive
structures were observed in the MOB with age. These results suggest that decrease in DCX-immunoreactive neuronal progenitors
and its protein levels in the MOB with age may be associated with reduction of cell proliferation in the SVZ and with an increase
in α-synuclein in the MOB. 相似文献
56.
In Koo Hwang Sun Shin Yi Jae Hoon Shin Ki-Yeon Yoo Jung Hoon Choi Choong Hyun Lee Je Kyung Seong Yeo Sung Yoon Jeong Ho Park Moo-Ho Won 《Neurochemical research》2010,35(3):465-472
In the present study, we observed the effects of cyclosporine A (CsA), an efficient immunosuppressant, on cell proliferation
and neuroblast differentiation in the subgranular zone of the dentate gyrus (SZDG) in normal C57BL/6 mice using Ki67 and doublecortin
(DCX) immunohistochemical staining, respectively. At 8 weeks of age, vehicle (physiological saline) or CsA was daily administered
(40 mg/kg, i.p.) for 1 week. Animals were sacrificed at 2 weeks after last administration. CsA treatment did not show any
influences in neurons, astrocytes and microglia based on immunohistochemistry for its markers, respectively. However, in the
CsA-treated group, Fluoro-Jade B, a marker for neurodegeneration, positive cells were found in the SZDG, not in the vehicle-treated
group. In the vehicle-treated group, Ki67 immunoreactive (+) nuclei were clustered in the SZDG, whereas in the CsA-treated group Ki67+ nuclei were scattered in the SZDG, showing no difference in cell numbers. Numbers of DCX+ neuroblasts with well-developed processes (tertiary dendrites) were much lower in the CsA-treated group than those in the
vehicle-treated group; however, numbers of DCX+ neuroblasts with secondary dendrites were similar in both the groups. These results suggest that CsA significantly reduces
dendritic outgrowth and complexity from neuroblasts in the SZDG without any affecting in neurons, astrocytes and microglia
in normal mice. 相似文献
57.
Rostand M. Ngoumfo Jean-Bosco Jouda Ferdinand T. Mouafo Justin Komguem Céline D. Mbazoa Tze Chieh Shiao Mohammed I. Choudhary Hartmut Laatsch Jean Legault André Pichette René Roy 《Bioorganic & medicinal chemistry》2010,18(10):3601-3605
Chemical investigation of the roots and fruits of Zanthoxylum leprieurii Guill. et Perr. led to the isolation of three new alkaloids including two acridone derivatives, 3-hydroxy-1,4-dimethoxy-10-methyl-9-acridone (2) and 3-hydroxy-1,2-dimethoxy-10-methyl-9-acridone (3) named helebelicine A and B, respectively, and one secobenzo[c]phenantridine, 10-O-demethyl-12-O-methylarnottianamide (10), together with thirteen other compounds. The structures of compounds 2, 3 and 10 as well as those of the known compounds were elucidated by using spectroscopic methods and by comparison with reported data. The brine-shrimp (artemia salina) lethality bioassay of the chloroform extract of the fruits showed modest cytotoxicity with LD50 at 13.1 μg/mL. Isolated compounds 1, 4–6 were found to be moderately active against lung carcinoma cells (A549), colorectal adenocarcinoma cells (DLD-1) and normal cells (WS1) with IC50 values ranging from 27 to 77 μM. In contrast to the positive control etoposide used, the cytotoxicity of the most active compound 4 was found to be selective against cancer cells in comparison to normal cells WS1 with IC50 of 51 ± 8 μM and 4.3 ± 0.4 μM, respectively. 相似文献
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59.
Leonardo Faoro Patrick A. Singleton Gustavo M. Cervantes Frances E. Lennon Nicholas W. Choong Rajani Kanteti Benjamin D. Ferguson Aliya N. Husain Maria S. Tretiakova Nithya Ramnath Everett E. Vokes Ravi Salgia 《The Journal of biological chemistry》2010,285(24):18575-18585
Non-small cell lung cancer (NSCLC) has a poor prognosis and improved therapies are needed. Expression of EphA2 is increased in NSCLC metastases. In this study, we investigated EphA2 mutations in NSCLC and examined molecular pathways involved in NSCLC. Tumor and cell line DNA was sequenced. One EphA2 mutation was modeled by expression in BEAS2B cells, and functional and biochemical studies were conducted. A G391R mutation was detected in H2170 and 2/28 squamous cell carcinoma patient samples. EphA2 G391R caused constitutive activation of EphA2 with increased phosphorylation of Src, cortactin, and p130Cas. Wild-type (WT) and G391R cells had 20 and 40% increased invasiveness; this was attenuated with knockdown of Src, cortactin, or p130Cas. WT and G391R cells demonstrated a 70% increase in focal adhesion area. Mammalian target of rapamycin (mTOR) phosphorylation was increased in G391R cells with increased survival (55%) compared with WT (30%) and had increased sensitivity to rapamycin. A recurrent EphA2 mutation is present in lung squamous cell carcinoma and increases tumor invasion and survival through activation of focal adhesions and actin cytoskeletal regulatory proteins as well as mTOR. Further study of EphA2 as a therapeutic target is warranted. 相似文献
60.
Carrier-mediated delivery of peptidic drugs for cancer therapy 总被引:2,自引:0,他引:2
Protein and peptide drugs are used for treatment of a variety of ailments. However, their wider use has been hindered by issues such as poor bioavailability in vivo and the cost involved in producing these drugs. This review discusses the various carrier-mediated methods used for delivery of peptide and protein drugs, with emphasis on liposomal and microspherical drug delivery systems. A brief look at the types of peptidic drugs currently in use clinically, and a brief discourse on several novel ideas for better protein delivery systems for cancer therapy is included. 相似文献