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Outcomes after surgery and postoperative radiotherapy for perineural spread of head and neck cutaneous squamous cell carcinoma 下载免费PDF全文
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Clare Barrington Anisha Gandhi Adrienne Gill Laura Villa Torres Maria Priscila Brietzke Lisa Hightow-Weidman 《Global public health》2018,13(10):1507-1519
Latinos in the U.S. are disproportionately affected by HIV and are more likely than non-Latinos to present with a late diagnosis, which delays engagement in HIV care and treatment. Social networks may provide normative influence and social support for HIV testing, but a contextualised understanding of networks is needed in order to maximise these social resources. We conducted qualitative interviews with foreign-born Latino men and transgender women (n?=?17) in a new immigrant destination to explore their social networks. Most participants described having smaller social networks after migrating. Networks included both local and transnational ties, but most participants had few close ties. Contextual factors including stigma and geographic dispersion limited the re-construction of networks with close ties after migration. HIV testing was not a common topic of discussion with social network ties. Efforts to improve early uptake of HIV testing among Latino immigrants may benefit from engaging with social networks, but such efforts need to address how the context in which networks operate enables access to testing. 相似文献
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Oncogenic AKAP9-BRAF fusion is a novel mechanism of MAPK pathway activation in thyroid cancer 总被引:10,自引:0,他引:10 下载免费PDF全文
Ciampi R Knauf JA Kerler R Gandhi M Zhu Z Nikiforova MN Rabes HM Fagin JA Nikiforov YE 《The Journal of clinical investigation》2005,115(1):94-101
Genes crucial for cancer development can be mutated via various mechanisms, which may reflect the nature of the mutagen. In thyroid papillary carcinomas, mutations of genes coding for effectors along the MAPK pathway are central for transformation. BRAF point mutation is most common in sporadic tumors. By contrast, radiation-induced tumors are associated with paracentric inversions activating the receptor tyrosine kinases RET and NTRK1. We report here a rearrangement of BRAF via paracentric inversion of chromosome 7q resulting in an in-frame fusion between exons 1-8 of the AKAP9 gene and exons 9-18 of BRAF. The fusion protein contains the protein kinase domain and lacks the autoinhibitory N-terminal portion of BRAF. It has elevated kinase activity and transforms NIH3T3 cells, which provides evidence, for the first time to our knowledge, of in vivo activation of an intracellular effector along the MAPK pathway by recombination. The AKAP9-BRAF fusion was preferentially found in radiation-induced papillary carcinomas developing after a short latency, whereas BRAF point mutations were absent in this group. These data indicate that in thyroid cancer, radiation activates components of the MAPK pathway primarily through chromosomal paracentric inversions, whereas in sporadic forms of the disease, effectors along the same pathway are activated predominantly by point mutations. 相似文献
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Perineural invasion is a common mechanism of spread of head and neck cancers. Imaging plays an important role in detection of this condition because a large number of patients with perineural spread (PNS) are clinically asymptomatic. Accurate detection of PNS requires an understanding of anatomy of commonly involved neural pathways. High level of suspicion on the part of the radiologist, awareness of common imaging signs of PNS and careful attention to imaging technique can aid in earlier detection of this condition. 相似文献
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Mitochondria are essential for cellular function due to their role in ATP production, calcium homeostasis and apoptotic signalling. Neurons are heavily reliant on mitochondrial integrity for their complex signalling, plasticity and excitability properties, and to ensure cell survival over decades. The maintenance of a pool of healthy mitochondria that can meet the bioenergetic demands of a neuron, is therefore of critical importance; this is achieved by maintaining a careful balance between mitochondrial biogenesis, mitochondrial trafficking, mitochondrial dynamics and mitophagy. The molecular mechanisms that underlie these processes are gradually being elucidated. It is widely recognized that mitochondrial dysfunction occurs in many neurodegenerative diseases, including Parkinson''s disease. Mitochondrial dysfunction in the form of reduced bioenergetic capacity, increased oxidative stress and reduced resistance to stress, is observed in several Parkinson''s disease models. However, identification of the recessive genes implicated in Parkinson''s disease has revealed a common pathway involving mitochondrial dynamics, transport, turnover and mitophagy. This body of work has led to the hypothesis that the homeostatic mechanisms that ensure a healthy mitochondrial pool are key to neuronal function and integrity. In this paradigm, impaired mitochondrial dynamics and clearance result in the accumulation of damaged and dysfunctional mitochondria, which may directly induce neuronal dysfunction and death. In this review, we consider the mechanisms by which mitochondrial dysfunction may lead to neurodegeneration. In particular, we focus on the mechanisms that underlie mitochondrial homeostasis, and discuss their importance in neuronal integrity and neurodegeneration in Parkinson''s disease.
LINKED ARTICLES
This article is part of a themed issue on Mitochondrial Pharmacology: Energy, Injury & Beyond. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2014.171.issue-8 相似文献69.
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Daryl Ramai Gandhi Lanke Jonathan Lai Mohamed Barakat Saurabh Chandan Andrew Ofosu Amaninder Dhaliwal Douglas G. Adler 《Pancreatology》2021,21(1):124-129
BackgroundPancreatic cancer is projected to become the second leading cause of cancer related death in the US. We aim to investigate the demographics, clinical outcomes and survival outcomes of patients diagnosed with early-onset (<40 years) and late-onset (>40 years) pancreatic adenocarcinoma (PAC).MethodsData on PAC between 1975 and 2016 were extracted from the Surveillance, Epidemiology, and End Results Registry.ResultsWithin the study period, 136,100 patients were identified which included 1181 patients with early-onset PAC and 134,919 patients with late-onset PAC. Both cohorts tend to present with distant metastasis (70.3% vs 57.9%). Both groups also showed an exponential rise in incidence (early-onset 3.69% annual change vs late-onset 6.25% annual change). When stratified by anatomical location, there was a trend of increasing cancer in the head of the pancreas for patients <40 years (3.63% annual change). While late PAC showed increasing cancer in all anatomical locations, the largest increase was observed in the tail of the pancreas (8.62% annual change). Overall, there was a mild difference in survival for early- and late-onset PAC (7 months vs 6 months, respectively, log rank p = 0.004). Both age groups showed the worse prognosis when cancer occurred in the tail of the pancreas (6 months vs 4 months, respectively). On cox proportion analysis, patients with late-onset PAC had twice the risk of mortality compared to early-onset PAC (HR 2.06, CI: 1.788–2.370, P = 0.001).ConclusionsOur study showed that both early- and late-onset PAC are increasing and while prognosis remains poor. Tumor anatomy showed a growing incidence of early-onset PAC in the head of the pancreas while late-onset PAC showed a rising incidence in the body and tail of the pancreas. 相似文献