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41.
Hepatocellular carcinoma (HCC), represents more than 85% of liver cancers. The diagnosis of HCC may be delayed due to the absence of early, sensitive and specific biomarkers. This study was conducted to investigate whether the expression of thioredoxin (Trx) and glutaredoxin (Grx) is helpful for HCC diagnosis in an experimental model. Twenty male albino rats were equally divided into two groups (HCC and control). Hepatocarcinogenesis was performed by single intraperitoneal (i.p) injection of 200?mg/kg of diethylnitrosamine (DENA). Two weeks later, 0.05% of phenobarbital (PB) was supplied in the drinking water for other 14 weeks. HCC was diagnosed by measuring serum alpha-fetoprotein (AFP) level and histopathological examination. Our results found that hepatic indices alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin were elevated but decreased total protein level. Lipid peroxidation was elevated through increasing hepatic content of MDA with decreased antioxidant parameters like hepatic SOD, CAT activities and GSH. The current study also found that Trx and Grx tissue genes were overexpressed in HCC group significantly, compared to control group. This study substantiated that increased expression of these enzymes may be predictive of outcomes in HCC.  相似文献   
42.
FDG PET/CT in carcinoma of unknown primary   总被引:1,自引:0,他引:1  
Carcinoma of unknown primary (CUP) is a heterogeneous group of metastatic malignancies in which a primary tumor could not be detected despite thorough diagnostic evaluation. Because of its high sensitivity for the detection of lesions, combined 18F-fluoro-2-deoxyglucose positron emission tomography (FDG PET)/computed tomography (CT) may be an excellent alternative to CT alone and conventional magnetic resonance imaging in detecting the unknown primary tumor. This article will review the use, diagnostic performance, and utility of FDG PET/CT in CUP and will discuss challenges and future considerations in the diagnostic management of CUP.  相似文献   
43.
The objective of this study was to determine the effect of storage time, temperature, and anticoagulant on hematologic parameters in equine blood samples. Blood samples were obtained from 50 clinically healthy warm-blooded horses at two major equestrian complexes in Tehran, Iran. The samples were collected in three different tubes containing EDTA, sodium citrate, or heparin and were analyzed within 4?h of collection. Blood samples collected into EDTA-containing tubes were stored at 4°C or 24°C. Each sample was analyzed again at 24, 48, and 72?h after collection. The statistically significant (P?<?0.05) alterations included decreased RBC count and increased hemoglobin concentration [Hgb] in blood samples stored at 24°C after 48 and 72?h; increased hematocrit in blood samples stored at 24°C after 24?h; decreased hematocrit in blood samples stored at 4°C after 72?h; decreased MCHC in blood samples stored at 4°C after 72?h; and decreased total WBC count in blood samples stored at 24°C after 48?h. Although there was no significant difference in hematologic analytes between heparinized and EDTA-anticoagulated blood samples, most of the hematologic analytes were decreased significantly (P?<?0.05) in sodium citrate-containing blood samples, compared with blood samples stored in EDTA. The results of this study suggest that within certain limitations for some hematologic analytes, equine blood samples stored in EDTA at 4°C for up to 72?h may be suitable for hematologic testing.  相似文献   
44.
We investigated the possible association between susceptibility to systemic lupus erythematosus (SLE) and single-nucleotide polymorphisms located in the promoter region of the interleukin-6 gene (?174 G/C) in a sample of the Egyptian population and the contribution of this polymorphism in the clinical or immunological manifestation of the disease. Forty-two Egyptian patients with SLE and 40 unrelated healthy control volunteers were genotyped by polymerase chain reaction followed by visualization on 4% agarose gel electrophoresis on ultraviolet transilluminator to detect the genotype distribution and allelic frequencies of the polymorphisms. The homozygous GG genotypes was significantly increased in SLE patients compared to control group (p value?=?0.04). On the other hand, the heterozygous G/C genotype was significantly elevated in the controls compared to SLE patients (p value?=?0.01). The odds ratio value for G/G was 2.6 with a 95% CI from 1.1 to 6.7. As regard the association of clinical manifestations to the genotype frequency, we found a statistical significant increase in the frequency of GG genotype with chest disease, nephritis, and arthritis. From this study, we suggest that G carrier is more susceptible to develop SLE and that SNP may have a role in the pathogenesis of the disease and may be associated with some of its clinical manifestations.  相似文献   
45.
Recent studies demonstrated the crucial role of c‐Rel in directing Treg lineage commitment and its involvement in T helper 1 (Th1) cell‐mediated autoimmune inflammation. We thus wondered whether these opposite functions of c‐Rel influence the course of antiparasitic immune responses against Leishmania major, an accepted model for the impact of T‐cell subsets on disease outcome. Here we show that c‐Rel‐deficient (rel?/?) mice infected with L. major displayed dramatically exacerbated leishmaniasis and enhanced parasite burdens. In contrast to WT mice, IFN‐γ and IL‐17 production in response to L. major antigens was severely impaired in rel?/? mice. Reconstitution of Rag1?/? T‐cell deficient mice with rel?/? CD4+ T cells followed by L. major infection demonstrated that c‐Rel‐deficient T cells mount normal Th1 responses and are able to contain the infection. Similarly, Th1 differentiation of naïve CD4+ cells in vitro was normal. Notably, a selective defect in IL‐12 and IL‐23 production was observed in rel?/? DCs compared with their WT counterparts. In conclusion, our data suggest that the expression of c‐Rel in myeloid cells is essential for clearance of L. major and that this c‐Rel‐mediated effect is dominant over the lack of Tregs.  相似文献   
46.
Summary Two patients with chronic regional enteritis with perforation are described, 1 of whom had free air under the diaphragm. It appears from a review of the reported cases of free perforation, that such a complication occurs more commonly in acute regional enteritis and, as in our patients, most often in the ileum.Our 2 patients are unusual in that (1) both of them showed histological changes of chronic regional enteritis, and (2) the first patient showed a pneumoperitoneum—which is very rare—seemingly being the fourth report in the literature of this condition.The occurrence of perforation in the bypassed loop of ileitis also reconfirms the advisability of resecting the pathologic segment whenever feasible.  相似文献   
47.
FDG-PET imaging has a number of advantages in the management of patients with lymphoma. PET shows a functional metabolic status and gives quantitative information. In addition, PET provides whole-body images that give a comprehensive assessment of disease extent during the staging and followup. Based on the present literature, FDG-PET is at least equivalent to CT for the initial staging of lymphomas. The impact of new technologies of combined PET/CT and fast-scanning CT with contrast has yet to be evaluated in the management of lymphoma patients, however. At this point, FDG-PET and CT must be considered as giving complementary staging information. FDG-PET also has high diagnostic accuracy for restaging lymphoma after initial treatment. FDG-PET has shown high accuracy in the early prediction of response to chemotherapy and in the evaluation of residual masses after chemotherapy or radiation therapy. Therefore, PET is likely to play a major role in tailoring the intensity of the treatment to the individual patient. A pretreatment FDG-PET study is essential for accurate assessment of residual masses and early monitoring of response to the treatment. In addition, a baseline PET scan will help detect relapse or residual disease, because relapse occurs most often in the region of previous disease.  相似文献   
48.
PURPOSE: In an effort to optimize sentinel lymph node (SLN) mapping for breast cancer, sites of mapping agent administration and types of mapping agents used continue to be evaluated. This study compares SLN mapping using peritumoral (PT) or subareolar (SA) injection of radiolabeled colloid and examines the relative contributions of radiotracer and blue dye to SLN identification. MATERIALS AND METHODS: A retrospective review was performed of 456 patients with breast cancer and clinically negative axillae who underwent SLN mapping. Sequential groups of patients were injected with filtered Tc-99m SC, 326 peritumorally (group 1) and 130 subareolarly (group 2). All patients had intraoperative SA injection of 1% isosulfan blue dye. RESULTS: The SLN identification and isotope success rates were 97% and 96% in group 1 and 98% and 98% in group 2, respectively. Eighty-one patients (25%) in group 1 and 44 patients (34%) in group 2 had positive SLNs. Of these patients, 15% from group 1 and 14% from group 2 had only positive nodes detected by radiotracer, and 9 of these patients (6 from group 1 and 3 from group 2) had other nodes identified by both radiotracer and blue dye that were negative for metastases. Six percent of patients with positive SLNs were upstaged because of use of radiotracer. CONCLUSIONS: PT and SA injection of radiotracer have comparable success rates for axillary SLN identification. Given that 15% of patients in group 1 and 14% in group 2 had only positive SLNs detected by radiotracer, independent of site of administration, radiotracer remains essential for optimizing breast SLN mapping.  相似文献   
49.
AIM: To determine whether or not fluorodeoxyglucose positron emission tomography (FDG PET) imaging when positive could obviate the necessity for sentinel lymph node biopsy and for complete axillary node dissection in patients with breast cancer. METHODS: A total of 80 female patients with a histological diagnosis of breast cancer and clinically negative axillary nodes underwent an FDG PET and sentinel lymph node biopsy (SLNB) or total axillary dissection for staging of axilla. Both SLNB and axillary dissection were performed in 72 patients, while eight patients had total axillary dissection without SLN biopsy. RESULTS: Of the 80 patients, 36 had lymph node metastasis on histopathology. SLNB was positive for metastasis in 35 (97%) of 36 patients (29 macrometastasis and seven micrometastasis). In the patient with false negative SLNB, the lymph node was completely replaced by the tumour. The FDG PET was true positive in 16 of 36 patients (sensitivity, 44%). There were two false positive studies with FDG PET, resulting in a specificity of 95%. The positive predictive value and accuracy of FDG PET for the detection of axillary lymph node metastasis were 89% and 72%, respectively. Univariate analysis revealed that higher grade of tumour, increased size and number of axillary lymph nodes were significantly associated with positive FDG PET results for axillary staging. CONCLUSION: FDG PET cannot replace histological staging using SLNB in patients with breast cancer. However, FDG PET has a high specificity and positive predictive value for staging of the axilla in these patients. The patients with higher grade of tumour, larger size and higher number of axillary lymph nodes may be considered for FDG PET scan for axillary staging.  相似文献   
50.
The purpose of this study was to assess the feasibility of PET imaging of oncogene VPAC1 receptors overexpressed in human breast cancer cells. METHODS: Vasoactive intestinal peptide (VIP) analog (TP3982) was synthesized to harbor a carboxy-terminus lysine (Lys) residue separated from VIP-asparagine (Asn(28)) by 4-aminobutyric acid (Aba) as a spacer. Lys was derivatized with diaminopropionic acid coupled to a pair of dibenzoylthioglycolic acid residues as protecting groups. The analog was labeled with (64)Cu at pH 9 ((64)Cu-TP3982) and (99m)Tc at pH 12 ((99m)Tc-TP3982). (99m)Tc-TP3982 and VIP derivatized with Aba-GAGG and labeled with (99m)Tc ((99m)Tc-TP3654) were used as reference agents. Smooth muscle relaxivity assays performed with each derivative and compared with unaltered VIP(28) demonstrated functional integrity. In vitro stability of (64)Cu-TP3982 was determined by challenging the complex with 100-mol excess of diethylenetriaminepentaacetic acid (DTPA), human serum albumin (HSA), and cysteine. In vivo stability was determined in urine and serum for up to 24 h. The mass of the Cu-TP3982 complex was determined by mass spectrometry. Human T47D breast tumor xenografts were grown in athymic nude mice. Planar scintigraphic imaging was performed at 4 and 24 h after the intravenous administration of (99m)Tc-TP3982 and (99m)Tc-TP3654 and PET imaging was performed using a small animal MOSAIC PET scanner, also at 4 and 24 h after injection of (64)Cu-TP3982. Tissue-distribution studies were also performed. In a separate experiment, receptors were blocked by intravenous injection of authentic VIP(28) 30 min before the administration of (64)Cu-TP3982 and tissue distribution was examined. RESULTS: (64)Cu-TP3982 labeling yields were 98% +/- 1.2% and those for (99m)Tc-TP3982 and (99m)Tc-TP3654 were 98.2% +/- 1.1% and 97% +/- 1.6%, respectively. The biologic activity of both VIP analogs was uncompromised. When (64)Cu-TP3982 was challenged with 100-mol excess of DTPA, HSA, or cysteine, >98% radioactivity remained as (64)Cu-TP3982. In vivo, >98% of (64)Cu circulating in plasma remained as (64)Cu-TP3982. Of the (64)Cu excreted in urine 4, 20, and 24 h after injection, >98%, 89.9% +/- 0.9%, and 85% +/- 3%, respectively, were bound to TP3982. The mass of Cu-TP3982 as determined by surface-enhanced laser desorption/ionization time of flight (SELDI-TOF) was 4,049.7 Da. Four hours after receptor blocking with VIP(28), there was a significant reduction in uptake of all tissues except in the liver. With (64)Cu-TP3982, the 4-h postinjection tumor uptake was 10.8 +/- 2.1 %ID/g versus 0.5 +/- 0.02 %ID/g and 0.24 +/- 0.08 %ID/g for (99m)Tc-TP3982 and (99m)Tc-TP3654, respectively. Twenty-four hours after injection, the corresponding numbers were 17 +/- 0.7 %ID/g, 0.77 +/- 0.1 %ID/g, and 0.23 +/- 0.1 %ID/g. The severalfold greater uptake (21.2-74) of (64)Cu-TP3982 is attributable to the in vivo stability of the agent. CONCLUSION: The results suggest that the uncompromised biologic activity and the significantly greater tumor uptake of (64)Cu-TP3982, combined with the high sensitivity and enhanced resolution of PET imaging, make (64)Cu-TP3982 highly desirable for further studies in PET imaging of oncogene receptors overexpressed in breast and other types of cancers.  相似文献   
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