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81.
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
82.
Y. Raja Rampersaud Stephen J. Lewis J. Roderick Davey Rajiv Gandhi Nizar N. Mahomed 《The spine journal》2014,14(2):234-243
Background contextIt is well accepted that total hip and knee arthroplasty (THA/TKA) for osteoarthritis (OA) is associated with reliable and sustained improvements in postoperative health-related quality of life (HRQoL). Although several studies have demonstrated comparable outcomes with THA/TKA after surgical intervention for lumbar spinal stenosis (LSS), the sustainability of the outcome after LSS surgery compared with THA/TKA remains uncertain.PurposeThe primary purpose of this study is to assess whether improvements in HRQoL after surgical management of focal lumbar spinal stenosis (FLSS) with or without spondylolisthesis are sustainable over the long term compared with that of THA/TKA for OA.Study designSingle-center, retrospective, longitudinal matched cohort study of prospectively collected outcomes, with a minimum of 5-year follow-up (FU).Patient samplePatients who had primary one- to two-level spinal decompression with or without instrumented fusion for FLSS and THA/TKA for primary OA.Outcome measuresPostoperative change from baseline to last FU in Short-Form 36 physical component summary (PCS) and mental component summary (MCS) scores among groups was used as the primary outcome measure.MethodsAn age, sex-matched inception cohort of primary one- to two-level spinal decompression with or without instrumented fusion for FLSS (n=99) was compared with a cohort of primary THA (n=99) and TKA (n=99) for OA and followed for a minimum of 5 years. Linear regression was used for the primary analysis.ResultsMean (percent) FUs in months were 80.5+16.04 (79%), 94.6+16.62 (92%), and 80.6+16.84 (85%) for the FLSS, THA, and TKA cohorts, respectively, with a range of 5 to 10 years for all three cohorts. The number of patients who have undergone revision including those lost to FU for the FLSS, THA, and TKA cohorts were n=20 (20.2%, same site [n=7] and adjacent segment [n=13]) requiring 27 operations, n=3 (3%, same site) requiring 5 operations, and n=8 (8.1%, same site) requiring 12 operations, respectively (p<.01). The average time to first revision was 56/65/43 months, respectively. Mean postoperative PCS (p<.0001) and MCS (p<.02) scores improved significantly and were durable for all groups at the last FU. The mean changes from baseline PCS/MCS scores to last FU were 8.5/6.4, 12.3/7.0, and 8.3/4.9 for FLSS, THA, and TKA, respectively. Adjusting for baseline age, sex, body mass index, PCS score, and MCS score, there was a strong trend in favor of greater sustained change in the PCS score of THA over FLSS (p=.07) and TKA (p=.08). No difference was noted for change in PCS score between FLSS and TKA (p=.95). No differences were noted for change in MCS score among all three cohorts (p>.1).ConclusionsSignificant improvements in HRQoL after surgical treatment of FLSS with or without spondylolisthesis and hip and knee OA are sustained for a mean of 7 to 8 years, with a minimum of 5-year FU. Despite a higher revision rate, patients undergoing surgery for FLSS can expect a comparable long-term average improvement in HRQoL from baseline compared with their peers undergoing TKA and to a lesser extent THA. 相似文献
83.
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84.
85.
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
86.
Eva Kapravelou Hugo Issa Gordon Culham Martin Hosking Sanjiv K. Gandhi Shubhayan Sanatani 《Congenital heart disease》2021,16(6):675-680
A 4-month-old previously healthy baby was found to be in congestive heart failure with LV dysfunction and a right aortic arch with severe coarctation, undetectable by blood pressure measurements. A cardiac CT and central blood pressure led to the diagnosis of a unique anatomic variant of aortic coarctation. Once diagnosed the patient underwent surgery with an uncomplicated recovery. 相似文献
87.
The herpesvirus Human Cytomegalovirus (HCMV) is an important opportunistic infection in recipients of allogeneic haemopoietic stem cell transplants, in whom HCMV-specific CD8+ and CD4+ T-cell responses are impaired. The nature of the HCMV-specific T-cell response in healthy virus carriers has been characterised in detail. High frequencies of circulating CD8+ T-cells that recognise defined viral peptides are maintained for years, and include individual CD8+ clones that have undergone extensive clonal expansion and phenotypic diversification in vivo. Following stem cell transplantation, the kinetics of HCMV-specific CD8+ T-cell reconstitution in the recipient are related to the presence or absence of antigen-experienced CD8+ T-cells transferred via the allograft, and to the presence of the virus in the recipient. We discuss recent progress in our understanding of HCMV-specific immunity in healthy virus carriers and in recipients after alloSCT. 相似文献
88.
Background
Advanced congestive heart failure (CHF) therapies include intravenous inotropic agents, change in class of diuretics, and venous ultrafiltration or hemodialysis. These modalities have not been associated with improved prognosis and are limited by availability and cost. Compared to high-dose furosemide alone, concomitant hypertonic saline solution (HSS) administration has demonstrated improved clinical outcomes with good safety profile.Methods
A literature search was conducted for randomized controlled trials that investigated the use of HSS in patients admitted to hospital with acute CHF.Results
1032 patients treated with HSS and 1032 controls, demonstrated decreased all-cause mortality in patients treat with HSS with RR of 0.56 (95% CI 0.41–0.76,p = 0.0003). 1012 patients treated with HSS and 1020 controls, demonstrated decreased heart failure hospital readmission with RR of 0.50 (95% CI 0.33–0.76,p = 0.001). Patients treated with HSS also demonstrated decreased hospital length of stay (p = 0.0002), greater weight loss (p < 0.00001), and preservation of renal function (p < 0.00001).Conclusion
The results of this meta-analysis demonstrate that in patients with advanced CHF concomitant hypertonic saline administration improved weight loss, preserved renal function, and decreased length of hospitalization, mortality and heart failure rehospitalization. A future adequately powered, multi-centre, placebo controlled, randomized, double dummy, blinded trial is needed to assess the benefit of hypertonic saline in patients with renal dysfunction, in diverse patient populations, as well using a patient population on optimal current heart failure treatment. Pending further validation, there is promise for hypertonic saline as an advanced therapy for the management of acute advanced CHF. 相似文献89.
90.