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21.
Sharma R Mondal A Sahoo M Kakar A Shankar LR Khanna CM Chopra MK Soni NL 《The Journal of the Association of Physicians of India》1999,47(5):488-491
One hundred and forty eight subjects with euthyroid solitary thyroid nodules (STN) were taken up for radionuclide perfusion study. They were found to have a cold STN on 99mTc thyroid static scan. All had fine needle aspiration cytology (FNAC), and except for subjects with chronic lymphocytic thyroiditis, were subjected to surgery for tissue diagnosis by histopathology. The diagnostic findings in these patients of solitary thyroid nodules were correlated with the histopathology. Radionuclide perfusion study is considered useful to differentiate benign from malignant cold thyroid solitary nodules with high degree of sensitivity (95%) and specificity (87.9%). 相似文献
22.
Fibroblast growth factor 2 induces differentiation and apoptosis of Askin tumour cells 总被引:7,自引:0,他引:7
Kim MS Kim CJ Jung HS Seo MR Juhnn YS Shin HY Ahn HS Thiele CJ Chi JG 《The Journal of pathology》2004,202(1):103-112
Peripheral primitive neuroectodermal tumour (PNET)/Ewing's sarcoma (ES) and neuroblastoma (NB) are related tumours of neural crest origin with primitive neural characteristics. Fibroblast growth factor 2 (FGF2) is a critical signalling molecule for primitive neural crest cells. The treatment of NB cells with FGF2 variably affects biological characteristics such as growth and differentiation, while in PNET/ES, FGF2 predominantly induces apoptosis. The JK-GMS Askin tumour cell line can be induced to differentiate upon treatment with nerve growth factor (NGF), indicating the integrity of the cellular machinery necessary for differentiation. The present study assesses whether FGF2 can induce differentiation in JK-GMS cells. JK-GMS cells expressed high-affinity FGF receptors (FGFRs), and treatment with FGF2 induced phosphorylation of FGFR1 together with activation of extracellular signal-regulated kinases (ERK1/ERK2) and c-Jun N-terminal kinase (JNK). Subsequent biological effects were growth inhibition, neuronal differentiation, and apoptosis, and these changes were associated with increased expression of neurofilaments, reduction of c-myc and bcl-2 expression, and activation of caspase 3. Treatment of the cells with a specific inhibitor of the MAPK/extracellular signal-regulated kinase (MEK)-1, PD98059, predominantly inhibited the effects of FGF2 on growth, differentiation, and apoptosis, while an inhibitor of JNK reduced apoptosis, indicating that the ERK1/2 and JNK pathways are critical components of FGF2-mediated effects in JK-GMS cells. Additional comparative analyses of FGF2-mediated effects in two ES cell lines (CADO-ES, RD-ES) and a PNET cell line (SK-N-MC) showed pronounced differentiation in SK-N-MC, but not in CADO-ES or RD-ES cells. This study demonstrates that FGF2 can induce neuronal differentiation of PNET including Askin tumour. These findings clearly indicate that the FGF2-mediated signalling pathway plays a critical role in controlling the major properties of PNET cells and may provide a potential therapeutic target for PNET. 相似文献
23.
Udayachander M Meenakshi A Sivakumar N Kumar RR Shankar SG Dean CJ Modjtahedi H 《Human antibodies》1999,9(3):149-154
Monoclonal antibody CIBCNSH3 of IgG1 isotype has been generated against human epidermal growth factor receptor (EGFR) using MDA MB 468 breast carcinoma cell line as immunogen. Earlier studies have revealed that this MAb blocked growth factor-receptor interaction and thus inhibited cell proliferation and tumor growth. In the present paper, this MAb has been extensively characterized to evaluate its application in the study of human cancers. The results were compared with those obtained using a control MAb ICR 62 specific to EGFR. Competitive assay showed that this MAb bound to an epitope in the extracellular domain of the EGFR to which MAb ICR 62 also bound. This MAb immunoprecipitated the 170 kD glycoprotein. The specificity was further confirmed by the formation of a single discrete band in western blot analysis. By flow cytometric analysis this monoclonal antibody revealed high binding affinity with MDA MB 468 cells. By immunocytochemical assay, out of 35 breast tumors studied, 40% were found to exhibit strong cell membrane staining and in the case of 25 oral cancers studied, 56% were strong positive. High expression of EGFR was observed in MDA MB 468 cells and HN 5 cells. These studies clearly indicate that MAb CIBCNSH3 might prove useful to identify tumors with high level of expression of EGFR associated with poor prognosis. 相似文献
24.
25.
Immediate breast reconstruction-impact on radiation management 总被引:1,自引:0,他引:1
Shankar RA Nibhanupudy JR Sridhar R Ashton C Goldson AL 《Journal of the National Medical Association》2003,95(4):286-295
Breast reconstruction is an option for women undergoing modified radical mastectomy due to a diagnosis of breast cancer. In certain patients, breast reconstruction is performed by insertion of a temporary tissue expander prior to the placement of permanent breast implants. Some of these patients, following mastectomy, may require chest wall irradiation to prevent loco regional relapse. The compatibility of radiation and tissue expanders placed in the chest wall is of major concern to the radiation oncologist. Clinically undetectable changes can occur in the tissue expander during the course of radiation therapy. This can lead to radiation treatment set-up changes, variation in tissue expansion resulting in unwanted cosmesis, and deviation from the prescribed radiation dose leading to over and/or under dosing of tumor burden. At Howard University hospital, a CT scan was utilized to evaluate the status of the temporary tissue expander during radiation treatment to enable us to prevent radiation treatment related complications resulting from dosimetric discrepancies. CT images of the tissue expander were obtained through the course of treatment. To avoid a 'geographic miss' the amount of fluid injected into the tissue expander was kept constant following patient's satisfaction with the size of the breast mound. The CT scans allowed better visualization of the prosthesis and its relation to the surrounding tumor bed. This technique ensured that anatomical changes occurring during radiation treatment, if any, were minimized. Repeated dosimetry evaluations showed no changes to the prescribed dose distribution. A CT of the reconstructed breast provides an important quality control. Further studies with greater number of patients are required for confirming this impact on radiation treatment. 相似文献
26.
Influence of age and HLA type on interferon-gamma (IFN-gamma) responses to a naturally occurring polymorphic epitope of Plasmodium falciparum liver stage antigen-1 (LSA-1) 下载免费PDF全文
Bucci K Kastens W Hollingdale MR Shankar A Alpers MP King CL Kazura JW 《Clinical and experimental immunology》2000,122(1):94-100
Antigenic polymorphism and HLA restriction may limit the immunogenicity of a subunit vaccine against liver-stage Plasmodium falciparum. We examined 59 clinical isolates and five laboratory clones of P. falciparum for polymorphism in the N- and C-terminal regions of LSA-1, evaluated binding of the corresponding peptides to selected HLA class I alleles, and measured IFN-gamma responses in residents of a malaria-endemic area of Papua New Guinea where HLA-A*1101, -24, -B13, and -B40 are the most common class I alleles. LSA-1 polymorphism was limited to a single non-synonymous mutation encoding serine (S), proline (P), or threonine (T) at amino acid 85. Nine-mer 84-92 peptides with S, T, or P at the primary anchor position bound differentially to HLA-A11, -A2, and -B7. IFN-gamma ELISPOT responses increased with age in malaria-exposed subjects: 14-16% and 30-36% of 2-5- and 6-54-year-olds, respectively, had > or =10 IFN-gamma-secreting cells/106 peripheral blood mononuclear cells when stimulated with at least one peptide variant (P<0.05). IFN-gamma responses to all three peptides were also greater for older than younger individuals. No children < 3 years old had lymphocytes that responded to all three 84-92 peptides, whereas 45% of adults (mean age 48 years) had aggregated IFN-gamma responses. These data support the notion that age-related cumulative exposure to P. falciparum increases the frequency of IFN-gamma responses to polymorphic epitopes of liver-stage antigens such as LSA-1. 相似文献
27.
Esaki Muthu Shankar Ramachandran Vignesh Kailapuri G Murugavel Pachamuthu Balakrishnan Ramalingam Sekar Charmaine AC Lloyd Suniti Solomon Nagalingeswaran Kumarasamy 《AIDS research and therapy》2007,4(1):1-7
Background
CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART. 相似文献28.
Leishmania donovani suppresses activated protein 1 and NF-kappaB activation in host macrophages via ceramide generation: involvement of extracellular signal-regulated kinase 下载免费PDF全文
Ghosh S Bhattacharyya S Sirkar M Sa GS Das T Majumdar D Roy S Majumdar S 《Infection and immunity》2002,70(12):6828-6838
29.
This study examined the prevalence and correlated factors of cigarette smoking in a cross-sectional, epidemiological survey of Korean American men living in Maryland (n=333). In this sample, 26.1% were current smokers and 42.3% were former smokers. The older age group (> or = 40 years) was more likely to have quit smoking than the younger age group (< 40 years). In multiple logistic regression analysis, acculturation was associated with smoking status; those who stayed more than 20 years in the U.S. were less likely to be current smokers (OR=0.32, 95% CI 0.13-0.77) than those who stayed less than 10 years. Alcohol use was associated with smoking status; those who consumed alcohol were more likely to be current smokers (OR=5.24, 95% CI 2.33-11.79) or former smokers (OR=5.45, 95% CI=2.69-11.04) than those did not. Those with hypertension were more likely to have quit smoking (OR=3.11, 95% CI=1.33-7.24). The results suggest that the role of acculturation in smoking status among Korean American men deserves further attention by researchers as well as by health professionals who develop smoking prevention and cessation programs. 相似文献
30.
Himi T. Kim Kihyun S. Kim Jai S. Kim Ward B. Stone 《Archives of environmental contamination and toxicology》1985,14(1):13-18
The PCBs, DDE, and mirex levels were measured in the subcutaneous fat and breast muscle of fifty-five waterfowl collected in New York State during 1981 and 1982. Levels were obtained by electron capture gas chromatography (EC-GC) on wet weight, dry weight, and lipid weight bases; results were confirmed by gas chromatography-mass spectrometry (GC-MS). The mean PCB levels were 6.1 (g/g in fat and 0.25 g/g in breast muscle on a wet weight basis. The mean DDE and mirex levels were 0.10 g/g and 0.28 g/g in fat and 0.01 g/g and 0.002 g/g in breast muscle on a wet weight basis, respectively.The results of the present study confirm those of the previous study (Kimet al. 1984). The detailed comparison, however, shows that the levels of PCBs and DDE in fat continued to decline while the level of mirex increased slightly. 相似文献