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41.
To understand whether the p53-regulated mdm2 gene expression was altered by the Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC), the NPC-TW01 cell line was infected by EBV through IgA receptor-mediated endocytosis. The mdm2 gene was expressed only in a small fraction of the NPC cell population and could be enhanced in the EBV-infected (EBV+) cells. In the animals bearing EBV+ and EBV- NPC xenografts, the MDM2+ cells only appeared in clusters in both EBV+ and EBV- tumors with stronger expression in EBV+ cells. Cotransfection of pmdm2-Luc plus pSV40-p53 plus pCMV-LMP1 in the NPC-TW06 line that had p53 heterozygous point mutation showed stronger mdm2 promoter activity than cells cotransfected with pmdm2-Luc plus pSV40-p53, but no mdm2 promoter activity was seen in cells cotransfected with pmdm2-Luc plus pCMV-LMP1. Only the EBV-LMP1 but not the EBV-LMP2A gene could enhance p53 to upregulated mdm2 expression. Tumor cells in NPC biopsy specimens revealed similar mdm2 expression as in the animal model. It is concluded that although EBV can indirectly enhance mdm2 gene expression in tumor cells that express this gene, it cannot turn on or directly regulate mdm2 expression in cells that do not express this gene. In other words, EBV plays a role as an enhancer in NPC tumorigenesis.  相似文献   
42.
Chen YH  Lee MF  Lan JL  Chen CS  Wang HL  Hwang GY  Wu CH 《Allergy》2005,60(12):1518-1523
BACKGROUND: Forcipomyia taiwana is a tiny, blood-sucking midge that cause intense pruritis and swelling in sensitive individuals. It is distributed island-wide in rural Taiwan and Southern China. Objective: This study aimed to study the allergic immune responses and identify F. taiwana allergens. METHODS: Crude whole body F. taiwana extracts were prepared with phosphate-buffered saline. The specific IgE antibody was determined by enzyme-linked immunoassay and immunoblotting. Protein was analyzed by electrospray ionization tandem mass spectrometry. RESULTS: Among the 372 subjects that were exposed to F. taiwana bites, 179 (48%) reported an immediate skin reaction with/without delay reaction and 41(11.1%) reported a solely delay reaction. The skin of 21 subjects was tested with F. taiwana extract. Of these 21 subjects, 12 (57.1%) produced immediate skin reactions and contained high levels of specific IgE antibody against F. taiwana. Immunoblotting revealed that 11 allergenic components are able to bind specific IgE. Allergens of 22, 24, 35, 36, and 64 kDa bound 50, 50, 75, 66.7, and 75% of IgE-containing sera tested, respectively. Tryptic fragments of the 24, 35, 36, and 64 kDa allergens were analyzed by ESI-MS/MS. Selected tryptic peptides of 24, 35, and 36, and 64 kDa allergens exhibited significant sequence identity with triosephosphate isomerase of Anopheles merus,Tenebrio molitor,Ochlerotatus togoi, and Chrysops vittatus, fructose 1,6-bisphosphate aldolase of Antheraea yamamai and Homalodisca coagulata, and a slow muscle myosin S1 heavy chain of Homarusamericanus and a protein with unknown function from A. gambiae, respectively. The 35 and 36 kDa proteins may represent different isoforms of the fructose 1,6-bisphosphate aldolase. CONCLUSION: We conclude that immediate reaction to F. taiwana bites is IgE mediated and the 24 (For t 1), 35 (For t 2), and 64 kDa (For t 3) proteins are candidates for major F. taiwana allergens. Further studies are needed to confirm these allergens.  相似文献   
43.
A micellar electrokinetic capillary chromatography (MECC) method for the simultaneous determination of seven biogenic amines in fish was developed. The peaks of all components were successfully separated within 11.5 min. MECC was performed with 0.06 M sodium deoxycholate in 0.02 M borate buffer (pH 9.2)-methanol (95:5, v/v) solvent. The average recoveries for all components ranged from 84.4 to 100.3%. The application of this method to detect amines in fried marlin fillet implicated in a food poisoning incident indicated that a high level (56.24 mg/100 g) of histamine was present in the sample. Another 10 fish samples collected from markets were also analyzed and did not contain detectable levels of histamine (<2.5 mg/100 g).  相似文献   
44.
Lin YT  Shau WY  Wang LF  Yang YH  Hwang YW  Tsai MJ  Tsao PN  Chiang BL 《Allergy》2000,55(7):641-646
BACKGROUND: The skin of patients with atopic dermatitis (AD) exhibits a striking susceptibility to colonization and infection by Staphylococcus aureus. The exotoxins secreted by S. aureus can act as superantigens and classic allergens, inducing the production of functionally relevant specific IgE antibodies. The aim of this study was to compare the levels and positive rates of serum staphylococcal enterotoxin A (SEA)- and staphylococcal enterotoxin B (SEB)-specific IgE between atopic children with and without AD. METHODS: Sixty children with AD, 55 children with respiratory allergy without AD, and 24 nonatopic healthy children were studied. The levels and positive rates of serum SEA- and SEB-specific IgE were compared among three groups. The correlation between the levels or positive rates of serum SEA/SEB-specific IgE and the severity of AD or the presence of previous skin infections was studied. RESULTS: The children with AD had significantly higher levels and positive rates of serum SEA- and SEB-specific IgE than the atopic children without AD (P < 0.001) and the nonatopic children (P < 0.001). There was no significant difference in the levels and positive rates of serum SEA- and SEB-specific IgE between the atopic children without AD and the nonatopic children. With or without adjustment for the potential confounding effect of total serum IgE levels, the levels and positive rates of serum SEA- and SEB-specific IgE were significantly correlated with severity of AD (P <0.005), but they were not significantly different between AD children with and without previous skin infections. CONCLUSIONS: SEA and SEB may contribute to chronic inflammation and exacerbation of AD through the IgE-mediated immune response.  相似文献   
45.
BackgroundDuctal prostate adenocarcinoma (DAC) is a rare, aggressive, histologic variant of prostate cancer that is treated with conventional therapies, similar to high-risk prostate adenocarcinoma (PAC).ObjectiveTo assess the outcomes of men undergoing definitive therapy for DAC or high-risk PAC and to explore the effects of androgen deprivation therapy (ADT) in improving the outcomes of DAC.Design, setting, and participantsA single-center retrospective review of all patients with cT1–4/N0–1 DAC from 2005 to 2018 was performed. Those undergoing radical prostatectomy (RP) or radiotherapy (RTx) for DAC were compared with cohorts of high-risk PAC patients.Outcome measurements and statistical analysisMetastasis-free survival (MFS) and overall survival (OS) rates were analyzed using Kaplan-Meier and Cox regression models.Results and limitationsA total of 228 men with DAC were identified; 163 underwent RP, 34 underwent RTx, and 31 had neoadjuvant therapy prior to RP. In this study, 163 DAC patients and 155 PAC patients undergoing RP were compared. Similarly, 34 DAC patients and 74 PAC patients undergoing RTx were compared. DAC patients undergoing RP or RTx had worse 5-yr MFS (75% vs 95% and 62% vs 93%, respectively, p < 0.001) and 5-yr OS (88% vs 97% and 82% vs 100%, respectively, p < 0.05) compared with PAC patients. In the 76 men who received adjuvant/salvage ADT after RP, DAC also had worse MFS and OS than PAC (p < 0.01). A genomic analysis revealed that 10/11 (91%) DACs treated with ADT had intrinsic upregulation of androgen-resistant pathways. Further, none of the DAC patients (0/15) who received only neoadjuvant ADT prior to RP had any pathologic downgrading. The retrospective nature was a limitation.ConclusionsMen undergoing RP or RTx for DAC had worse outcomes than PAC patients, regardless of the treatment modality. Upregulation of several intrinsic resistance pathways in DAC rendered ADT less effective. Further evaluation of the underlying biology of DAC with clinical trials is needed.Patient summaryThis study demonstrated worse outcomes among patients with ductal adenocarcinoma of the prostate than among high-grade prostate adenocarcinoma patients, regardless of the treatment modality.  相似文献   
46.
47.
Annals of Surgical Oncology - De-escalation of axillary surgery after neoadjuvant chemotherapy (NAC) requires careful patient selection. We seek to determine predictors of nodal pathologic complete...  相似文献   
48.
PurposeRenal function outcomes following robot-assisted radical cystectomy (RARC) have not been well established. We sought to compare long-term renal function outcomes between open radical cystectomy, RARC with extracorporeal urinary diversion and intracorporeal urinary diversion at a high volume institution.Materials and MethodsWe retrospectively reviewed our institutional bladder cancer database for patients who underwent RC from 2010 to 2019 with pre-operative estimated glomerular filtration rate (eGFR) > 45 ml/min/1.73m2. Changes in renal function were assessed through locally weighted scatter plot smoothing and comparison of median eGFR between surgical groups. Chronic Kidney Disease Stage 3B was defined as eGFR < 45 ml/min/1.73m2. Renal function decline was defined as a ≥10 ml/min/1.73m2 drop in eGFR. Kaplan Meier method with log-rank was used to compare CKD 3B-free survival and renal function decline. Cox Proportional Hazards model was used to identify predictors of CKD 3B.ResultsSix hundred and forty four patients were included with median follow-up of 32 months (IQR 12–56). Preoperative characteristics were similar among the groups with no differences in median pre-operative eGFR (ORC: 74.6, extracorporeal urinary diversion: 74.3, intracorporeal urinary diversion: 71.6 ml/min/1.73m2, P = 0.15). Median postoperative eGFR on follow up was not different between groups (P = 0.56). 33% of patients developed CKD 3B. There were no differences in CKD 3B-free survival by surgical approach (P = 0.23) or urinary diversion (P = 0.09). 64% of patients experienced renal function decline with a median time of 2.4 years (P 0.23). Predictors of CKD were pathologic T3 disease or greater (HR: 1.77, P = 0.01), ureteroenteric anastomotic stricture (HR: 2.80, P < 0.001), preoperative CKD Stage 2 (HR: 1.81, P =0.02), and preoperative CKD Stage 3A (HR: 5.56, P < 0.001).ConclusionRenal function decline is common after RC. Tumor stage, pre-operative eGFR, and ureteral stricture development, not surgical approach, influence renal function decline.  相似文献   
49.
Previous studies have reported reduced bone mineral density (BMD) in patients with hyperthyroidism. We assessed the association of BMD in children and adolescents with Graves’ disease (GD) after correcting for potential confounders affecting BMD such as age, sex, and pubertal status. Forty-four children and adolescents with GD and 172 age- and sex-matched healthy controls were enrolled in this study. We analyzed auxological features, BMD, and levels of thyroid hormone, thyroid-stimulating hormone, and thyroid autoantibodies. We measured BMD by dual-energy X-ray absorptiometry at the time of diagnosis in all patients. The mean age of all patients with GD (9 boys and 32 girls) was 12.1 ± 2.2 years (range, 7.0–16.0). Their initial mean free T4 and thyroid-stimulating hormone levels were 3.51 ± 1.56 ng/dL and 0.04 ± 0.03 IU/L, respectively. The mean BMD Z-scores of the lumbar spine (LS), femoral neck, and total body less head of patients with GD were significantly lower than those of control subjects. Eleven patients (26.8%) had low bone density (LS BMD Z-scores < ?2.0). To identify correlations of patient characteristics with BMD Z-scores at each site, alkaline phosphatase had a significant negative correlation with BMD Z-scores at LS and femoral neck, but not total body less head (r = ?0.441; p = 0.004 and r = ?0.351; p = 0.025, respectively). Children and adolescents with newly diagnosed GD had lower bone mass than their healthy peers. These results suggest that BMD measurement at initial evaluation may be necessary in this population.  相似文献   
50.
Indwelling urethral catheter placement is a common and comparatively safe procedure. Misplacement of a urethral catheter into the upper urinary tract is unusual, and only a few cases have been reported. We describe the case of a 43-year-old man who presented with oliguria and had a history of chemotherapy for known metastatic lung cancer. As he had no history of urological disease, urethral catheterization was expected to be uneventful. The catheter was unable to be pulled back to the bladder neck once the balloon was inflated, and the patient expressed discomfort. Subsequent computed tomography revealed that the tip of the catheter was placed in the middle of the right ureter. Unbeknownst to the physicians before urethral catheterization, the patient had severe lower urinary tract symptoms and urinary bladder dysfunction with hydronephrosis, likely due to chemotherapy. Based on the patient’s symptoms and imaging results, we judged the possibility of severe ureteral injury to be low. The malpositioned catheter was removed uneventfully after complete balloon deflation and then reinserted properly. He was admitted to the medical department but died as a result of an exacerbation of the underlying disease unrelated to the incident. If urethral catheter placement seems abnormal, physicians should aspirate and irrigate to confirm correct positioning before balloon inflation; then, they should carefully pull the inflated balloon near the neck of the bladder while monitoring the patient’s symptoms. Although urethral catheter placement is comparatively safe, physicians must keep in mind that patients who have undergone chemotherapy might be at a risk for this rare complication.  相似文献   
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