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51.
This study demonstrates that both the clinical sensitivity and specificity of the Cervista HPV HR test for high-risk human papillomavirus (HPV) detection are not inferior to those of the Hybrid Capture 2 (HC2) test. The intra- and interlaboratory reproducibilities of Cervista were 92.0% (kappa, 0.83) and 90.4% (kappa, 0.80), respectively. The Cervista HPV HR test fulfills all the international HPV test requirements for cervical primary screening purposes.  相似文献   
52.
Specific organochlorines (OCs) have been associated with non-Hodgkin lymphoma (NHL) with varying degrees of evidence. These associations have not been evaluated in Asia, where the high exposure and historical environmental contamination of certain OC pesticides (e.g., dichlorodiphenyltrichloroethane [DDT], hexachlorocyclohexane [HCH]) are different from Western populations. We evaluated NHL risk and prediagnostic blood levels of OC pesticides/metabolites and polychlorinated biphenyl congeners in a case–control study of 167 NHL cases and 167 controls nested within three prospective cohorts in Shanghai and Singapore. Conditional logistic regression was used to analyze lipid-adjusted OC levels and NHL risk. Median levels of p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE), the primary DDT metabolite, and β-HCH were up to 12 and 65 times higher, respectively, in samples from the Asian cohorts compared to several cohorts in the United States and Norway. An increased risk of NHL was observed among those with higher β-HCH levels both overall (3rd vs. 1st tertile OR = 1.8, 95%CI = 1.0–3.2; ptrend = 0.049) and after excluding cases diagnosed within 2 years of blood collection (3rd vs. 1st tertile OR = 2.0, 95%CI = 1.1–3.9; ptrend = 0.03), and the association was highly consistent across the three cohorts. No significant associations were observed for other OCs, including p,p′-DDE. Our findings provide support for an association between β-HCH blood levels and NHL risk. This is a concern because substantial quantities of persistent, toxic residues of HCH are present in the environment worldwide. Although there is some evidence that DDT is associated with NHL, our findings for p,p′-DDE do not support an association.  相似文献   
53.
54.
KRAS oncogene mutations cause sustained signaling through the MAPK pathway. Concurrent inhibition of MEK, EGFR, and HER2 resulted in complete inhibition of tumor growth in KRAS-mutant (KRASm) and PIK3CA wild-type tumors, in vitro and in vivo. In this phase I study, patients with advanced KRASm and PIK3CA wild-type colorectal cancer (CRC), non-small cell lung cancer (NSCLC), and pancreatic cancer, were treated with combined lapatinib and trametinib to assess the recommended phase 2 regimen (RP2R). Patients received escalating doses of continuous or intermittent once daily (QD) orally administered lapatinib and trametinib, starting at 750 mg and 1 mg continuously, respectively. Thirty-four patients (16 CRC, 15 NSCLC, three pancreatic cancers) were enrolled across six dose levels and eight patients experienced dose-limiting toxicities, including grade 3 diarrhea (n = 2), rash (n = 2), nausea (n = 1), multiple grade 2 toxicities (n = 1), and aspartate aminotransferase elevation (n = 1), resulting in the inability to receive 75% of planned doses (n = 2) or treatment delay (n = 2). The RP2R with continuous dosing was 750 mg lapatinib QD plus 1 mg trametinib QD and with intermittent dosing 750 mg lapatinib QD and trametinib 1.5 mg QD 5 days on/2 days off. Regression of target lesions was seen in 6 of the 24 patients evaluable for response, with one confirmed partial response in NSCLC. Pharmacokinetic results were as expected. Lapatinib and trametinib could be combined in an intermittent dosing schedule in patients with manageable toxicity. Preliminary signs of anti-tumor activity in NSCLC have been observed and pharmacodynamic target engagement was demonstrated.  相似文献   
55.
Pheochromocytomas and paragangliomas are neuroendocrine neoplasias of neural crest origin. Genetic mutations that are characterized in other human neoplasms are rarely seen in these tumors. About 10% of the patients with pheochromocytomas and paragangliomas present with a family history of von Hippel-Lindau disease (VHL), Multiple endocrine neoplasia type 2 (MEN2), one of the three familial paraganglioma syndromes (PGL; PGL1, PGL3, PGL4), or neurofibromatosis type 1 (NF1). In an even higher percentage, a genetic predisposition is involved in the development of these tumors. The genes of hereditary tumor syndromes such as the aforementioned ones are also ideal to study the molecular pathogenesis in the sporadic counterparts. Many studies have been undertaken to identify important secondary genetic events that contribute to the tumorigenesis of pheochromocytoma or paraganglioma, but a comprehensive review of these data is lacking. Recent findings of CGH and LOH studies provided new starting points to unravel the pathogenesis and progression of these tumors. This review presents an overview of our current understanding of the molecular pathogenesis of pheochromocytoma and paraganglioma. This work has been presented at the Endocrine Pathology Society meeting of the 92nd annual USCAP meeting in Washington DC, March 22, 2003.  相似文献   
56.
Omalizumab (a recombinant, humanized anti-immunoglobulin-E anti-body) has been shown in three pivotal Phase III trials (ASTERIA I, II and GLACIAL) and real-world studies to be effective and well-tolerated for the treatment of chronic spontaneous urticaria (CSU), and is the only licensed third-line treatment for CSU. However, the definition of response to omalizumab treatment often differs between clinical trials, real-world studies, and daily practice of individual physicians globally. As such, a consensus definition of “complete”, “partial” and “non-response” to omalizumab is required in order to harmonize treatment management and compare data. Here, it is proposed that a disease measurement tool, for example, the 7-Day Urticaria Activity Score (UAS7) or Urticaria Control Test (UCT) is required for defining response. The addition of quality of life measurements is helpful to gain insight into a patient’s disease burden and its changes during treatment. A potential omalizumab treatment approach based on speed and pattern of response at 1-3 and 3-6 months is suggested. In cases where there is no response during the first 1-3 months, physicians should consider reassessing the original CSU diagnosis. Moreover, in patients showing partial response at 12 weeks, treatment with omalizumab should be continued in order to maximize the possibility of achieving symptom control. If patients have a UAS7>6 and/or UCT<12, then continued treatment is advised, dependent on physician judgement and patient expectations. In treatment responders, omalizumab treatment can be resumed at a later stage after discontinuation with the same degree of symptom control.  相似文献   
57.
Cardiac allograft vasculopathy (CAV) causes heart failure after heart transplantation (HTx), but its pathogenesis is incompletely understood. Notch signaling, possibly modulated by everolimus (EVR), is essential for processes involved in CAV. We hypothesized that circulating Notch ligands would be dysregulated after HTx. We studied circulating delta‐like Notch ligand 1 (DLL1) and periostin (POSTN) and CAV in de novo HTx recipients (n = 70) randomized to standard or EVR‐based, calcineurin inhibitor‐free immunosuppression and in maintenance HTx recipients (n = 41). Compared to healthy controls, plasma DLL1 and POSTN were elevated in de novo (P < .01; P < .001) and maintenance HTx recipients (P < .001; P < .01). Use of EVR was associated with a treatment effect for DLL1. For de novo HTx recipients, a change in DLL1 correlated with a change in CAV at 1 (P = .021) and 3 years (P = .005). In vitro, activation of T cells increased DLL1 secretion, attenuated by EVR. In vitro data suggest that also endothelial cells and vascular smooth muscle cells (VSMCs) could contribute to circulating DLL1. Immunostaining of myocardial specimens showed colocalization of DLL1 with T cells, endothelial cells, and VSMCs. Our findings suggest a role of DLL1 in CAV progression, and that the beneficial effect of EVR on CAV could reflect a suppressive effect on DLL1. Trial registration numbers— SCHEDULE trial: ClinicalTrials.gov NCT01266148; NOCTET trial: ClinicalTrials.gov NCT00377962.  相似文献   
58.
OBJECTIVE: This review was undertaken to determine whether high intracranial pressure (ICP) during reperfusion after hypothermic circulatory arrest (HCA) correlates with evidence of suboptimal cerebral protection in a chronic porcine model. METHODS: In concurrent studies of cerebral protection, 48 control pigs (24-31 kg) underwent 90 min of HCA at 20 degrees C using a strictly standardized protocol. Hemodynamic measurements, ICP and neurophysiological data (EEG, SSEP) were assessed before HCA and until 3 h postoperatively. ICP was measured using a Codman microtip catheter inserted directly into brain parenchyma. Neurological/behavioral evaluation (9=full recovery) was carried out daily through postoperative day (POD) 3. RESULTS: There were no significant hemodynamic or metabolic differences between individual animals. ICP (mmHg) increased significantly for the first 3 h after HCA: from baseline levels of 6.2+/-2.1 to 10+/-2.6 at 1 h, 11+/-3.2 at 2 h and 10+/-3.6 mmHg at 3 h; P<0.001 for the trend. EEG recovery 3 h after HCA was observed in 13 animals (27%), and correlated with lower ICP during reperfusion (P<0.001): with each 1 mmHg increase in ICP at 3 h, the odds of early EEG recovery decreased by a factor of 0.72. Lower ICP during reperfusion was also significantly associated with higher behavioral scores on POD 1 and 2, P<0.001. CONCLUSIONS: A significant rise in ICP may help explain the prolonged obtundation and confusion often seen clinically after HCA. If these small but consistent increases in ICP contribute to rather than reflect ischemic neuronal damage, simple maneuvers to reduce ICP may improve cerebral recovery after HCA.  相似文献   
59.
OBJECTIVE: To assess the effect of hypercholesterolemia on neointima formation and vascular remodelling after porcine coronary angioplasty. METHODS: Left anterior descending coronary angioplasty was carried out in five control and 16 age-matched hypercholesterolemic miniature pigs. Vascular remodelling was measured by intravascular ultrasound. Neointima size and composition were assessed by quantitative image analysis. Coronary smooth muscle cells (SMC) from control and diet pigs were collected 1 h after angioplasty for in vitro study of the effect of hypercholesterolemic serum on SMC migration and of macrophage-induced matrix degradation on SMC adhesion. RESULTS: Twenty-eight days after angioplasty, lumen increase was 0.08+/-1.7 mm(2) in diet and 2.7+/-2.7 mm(2) (P=0.016) in control pigs. Lumen increase correlated with vascular remodelling (IEL(post)/IEL(pre); R(2)=0.59; P<0.001) and with the circumferential gain relative to the neointima (R(2)=0.32; P<0.01) but not with neointimal area that was similar in control and diet pigs. Circumferential gain correlated with VSMC deposition at the site of the injury (R(2)=0.28; P<0.01) that correlated with organized collagen (R(2)=0.34; P<0.01). The VSMC and collagen content of neointima in diet pigs was lower whereas the macrophage content was higher. Hypercholesterolemic serum and oxidised LDL reduced migration of VSMC from diet pigs. Macrophage-induced degradation of VSMC extracellular matrix reduced VSMC adhesion (P=0.015). CONCLUSION: Hypercholesterolemia impairs vascular remodelling of balloon-treated coronary arteries. It decreases VSMC and collagen accumulation at the site of injury. Our in vitro data suggest that this decrease can be due to macrophage-induced matrix degradation and reduced VSMC adhesion and to impaired VSMC migration. Oxidised LDL mimics the inhibitory effect of hypercholesterolemic serum.  相似文献   
60.
OBJECTIVE: To study the effect of dietary cholesterol withdrawal on size and composition of LDL-hypercholesterolemia-induced coronary plaques in miniature pigs. METHODS: Pigs were on normal chow (control group), on a cholesterol-rich diet for 37 weeks (hypercholesterolemic group) or on a cholesterol-rich diet followed by normal chow for 26 weeks (cholesterol withdrawal group). Endothelial function was assessed with quantitative angiography after intracoronary infusion of acetylcholine, plaque load with intra-coronary ultrasound and plaque composition with image analysis of cross-sections. The effect of porcine serum on coronary smooth muscle cell (SMC) function was studied in vitro. RESULTS: Cholesterol-rich diet caused LDL-hypercholesterolemia, increased plasma levels of oxidized LDL (ox-LDL) and C-reactive protein (CRP), and induced endothelial dysfunction and coronary atherosclerosis. Dietary cholesterol withdrawal lowered LDL, ox-LDL and CRP. It restored endothelial function, did not affect plaque size but decreased lipid, ox-LDL and macrophage content. Smooth muscle cells and collagen accumulated within the plaque. Increased smoothelin-to-alpha-smooth muscle actin ratio indicated a more differentiated SMC phenotype. Cholesterol lowering reduced proliferation and apoptosis. In vitro, hypercholesterolemic serum increased SMC apoptosis and decreased SMC migration compared to non-hypercholesterolemic serum. CONCLUSIONS: Cholesterol lowering induced coronary plaque stabilization as evidenced by a decrease in lipids, ox-LDL, macrophages, apoptosis and cell proliferation, and an increase in differentiated SMC and collagen. Increased migration and decreased apoptosis of SMC may contribute to the disappearance of the a-cellular core after lipid lowering.  相似文献   
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