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Alterations in the Wnt/β‐catenin pathway define a key event in the pathogenesis of colon cancer. We have recently shown that CDK8, the gene encoding a cyclin‐dependent kinase (CDK) component of the Mediator complex, acts as a colon cancer oncogene that is necessary for β‐catenin activity. Here, we tested the hypothesis that colorectal cancers with CDK8 expression have distinct clinical, prognostic and molecular attributes. Among 470 colorectal cancers identified in 2 prospective cohort studies, CDK8 expression was detected in 329 (70%) tumors by immunohistochemistry. Cox proportional hazards model and backward stepwise elimination were used to compute hazard ratio (HR) of deaths according to CDK8 status, initially adjusted for various patient and molecular features, including β‐catenin, p53, p21, p27 (CDK inhibitors), cyclin D1, fatty acid synthase (FASN), cyclooxygenase‐2 (COX‐2), microsatellite instability (MSI), CpG island methylator phenotype (CIMP), LINE‐1 methylation, and mutations in KRAS, BRAF and PIK3CA. CDK8 expression in colorectal cancer was independently associated with β‐catenin activation (p = 0.0002), female gender (p < 0.0001) and FASN overexpression (p = 0.0003). Among colon cancer patients, CDK8 expression significantly increased colon cancer‐specific mortality in both univariate analysis [HR 1.70; 95% confidence interval (CI), 1.03–2.83; p = 0.039] and multivariate analysis (adjusted HR 2.05; 95% CI, 1.18–3.56; p = 0.011) that was adjusted for potential confounders including β‐catenin, COX‐2, FASN, LINE‐1 hypomethylation, CIMP and MSI. CDK8 expression was unrelated with clinical outcome among rectal cancer patients. These data support a potential link between CDK8 and β‐catenin, and suggest that CDK8 may identify a subset of colon cancer patients with a poor prognosis.  相似文献   
94.
Objective: Because the etiology of thyroid cancer is not well described, we conducted a pooled analysis of all published case- control studies, as well as two identified unpublished studies. This paper describes the major characteristics of the 14 studies included in the analysis, as well as the statistical methods employed. Four studies were conducted in the United States (1 each in Washington State, California, Connecticut and Hawaii), 8 in Europe (3 in Sweden, 2 in Norway, 1 in Switzerland, 1 in Italy and 1 in Greece), and 2 in Asia (1 in China and 1 in Japan).Methods: The original datasets were obtained and restructured in a uniform format. Data on socio-demographic characteristics, anthropometric measures, smoking and alcohol consumption, history of benign thyroid diseases and of other selected medical conditions and treatments, family history of cancer and of benign thyroid conditions, occupation, residence in endemic goitre areas, and dietary habits were analyzed. For women, we also analyzed menstrual and reproductive factors and use of female hormones. Radiotherapy and, in Japan, exposure to the A-bombs were considered as potential confounding factors.Results: A total of 2,725 cases (2,247 females and 478 males) and 4,776 controls (3,699 females and 1,077 males) were included in this study. Of the cases, 79% were classified as papillary thyroid carcinomas, 14% as follicular, 2% medullary, 1% anaplastic, 1% other histologies, and 3% histological type unknown. Each of the datasets was checked for outliers and consistency. Data were analysed separately by study center, gender, and the two major histologic types (papillary, follicular). Frequency tables and simple statistics were computed for each variable under study. Conditional logistic regression was used to compute odds ratios. For matched studies, the original matching was preserved, whereas, for unmatched ones, five-year age groups were used for matching. Study-specific analyses were computed, and then the data from all the studies were pooled conditioning on study. Heterogeneity between studies, geographic areas and study designs was assessed, and the modifying effect of age was also evaluated.  相似文献   
95.
BackgroundRegular follow-up after treatment for breast cancer is crucial to detect potential recurrences and second contralateral breast cancer in an early stage. However, information about follow-up patterns in the Netherlands is scarce.Patients and MethodsDetails concerning diagnostic procedures and policlinic visits in the first 5 years following a breast cancer diagnosis were gathered between 2009 and 2019 for 9916 patients from 4 large Dutch hospitals. This information was used to analyze the adherence of breast cancer surveillance to guidelines in the Netherlands. Multivariable logistic regression was used to relate the average number of a patient’s imaging procedures to their demographics, tumor–treatment characteristics, and individual locoregional recurrence risk (LRR), estimated by a risk-prediction tool, called INFLUENCE.ResultsThe average number of policlinic contacts per patient decreased from 4.4 in the first to 2.0 in the fifth follow-up year. In each of the 5 follow-up years, the share of patients without imaging procedures was relatively high, ranging between 31.4% and 33.6%. Observed guidelines deviations were highly significant (P < .001). A higher age, lower UICC stage, and having undergone radio- or chemotherapy were significantly associated with a higher chance of receiving an imaging procedure. The estimated average LRR-risk was 3.5% in patients without any follow-up imaging compared with 2.3% in patients with the recommended number of 5 imagings.ConclusionCompared to guidelines, more policlinic visits were made, although at inadequate intervals, and fewer imaging procedures were performed. The frequency of imaging procedures did not correlate with the patients’ individual risk profiles for LRR.  相似文献   
96.
Tobacco smoking continues to cause considerable premature mortality and morbidity worldwide. Most of the approximately six trillion cigarettes sold globally each year are discarded improperly as toxic environmental waste. Tobacco product waste, including cigarette butts, is the most commonly collected waste item worldwide. Of particular concern is the cellulose acetate filter, a poorly degradable plastic additive attached to most commercially manufactured cigarettes. This filter was introduced by the tobacco industry to reduce smokers’ perception of harm and risk but it has no health benefit. To inform health policy and practice and improve public health outcomes, governments and society can benefit from cost estimates of preventing, properly disposing of and/or cleaning up tobacco product waste. Estimating the costs of tobacco product waste to communities and responsible authorities could encourage the development of health, environmental and fiscal policy interventions and shift accountability for the costs of tobacco product waste onto the global tobacco industry. To support health and environmental policy-making, we therefore propose an empirical approach to estimate the economic costs of tobacco product waste based on its negative environmental externalities. We first present general estimates for six representative countries and then identify data gaps that need to be addressed to develop global estimates. Interventions against tobacco product waste may be new channels to regulate tobacco products across sectors – for example, health, environment and finance – and consequently reduce overall tobacco use.  相似文献   
97.
We collected data on mass mortality in Sandwich terns (Thalasseus sandvicensis) during the 2022 breeding season in the Netherlands. Mortality was associated with at least 2 variants of highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b. We report on carcass removal efforts relative to survival in colonies. Mitigation strategies urgently require structured research.  相似文献   
98.
Abrin is a highly toxic protein obtained from the seeds of the rosary pea plant Abrus precatorius, and it is closely related to ricin in terms of its structure and chemical properties. Both toxins inhibit ribosomal function, halt protein synthesis and lead to cellular death. The major clinical manifestations following pulmonary exposure to these toxins consist of severe lung inflammation and consequent respiratory insufficiency. Despite the high similarity between abrin and ricin in terms of disease progression, the ability to protect mice against these toxins by postexposure antibody-mediated treatment differs significantly, with a markedly higher level of protection achieved against abrin intoxication. In this study, we conducted an in-depth comparison between the kinetics of in vivo abrin and ricin intoxication in a murine model. The data demonstrated differential binding of abrin and ricin to the parenchymal cells of the lungs. Accordingly, toxin-mediated injury to the nonhematopoietic compartment was shown to be markedly lower in the case of abrin intoxication. Thus, profiling of alveolar epithelial cells demonstrated that although toxin-induced damage was restricted to alveolar epithelial type II cells following abrin intoxication, as previously reported for ricin, it was less pronounced. Furthermore, unlike following ricin intoxication, no direct damage was detected in the lung endothelial cell population following abrin exposure. Reduced impairment of intercellular junction molecules following abrin intoxication was detected as well. In contrast, similar damage to the endothelial surface glycocalyx layer was observed for the two toxins. We assume that the reduced damage to the lung stroma, which maintains a higher level of tissue integrity following pulmonary exposure to abrin compared to ricin, contributes to the high efficiency of the anti-abrin antibody treatment at late time points after exposure.  相似文献   
99.
Highly Pathogenic Avian Influenza Viruses (HPAIVs) arise from low pathogenic precursors following spillover from wild waterfowl into poultry populations. The main virulence determinant of HPAIVs is the presence of a multi-basic cleavage site (MBCS) in the hemagglutinin (HA) glycoprotein. The MBCS allows for HA cleavage and, consequently, activation by ubiquitous proteases, which results in systemic dissemination in terrestrial poultry. Since 1959, 51 independent MBCS acquisition events have been documented, virtually all in HA from the H5 and H7 subtypes. In the present article, data from natural LPAIV to HPAIV conversions and experimental in vitro and in vivo studies were reviewed in order to compile recent advances in understanding HA cleavage efficiency, protease usage, and MBCS acquisition mechanisms. Finally, recent hypotheses that might explain the unique predisposition of the H5 and H7 HA sequences to obtain an MBCS in nature are discussed.  相似文献   
100.
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