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Epidemiological studies have demonstrated clear associations between specific dietary and environmental risk factors and incidence of colorectal cancer, but the mechanisms responsible for these associations are not known. An animal model could facilitate such an understanding. Both genotoxic and nongenotoxic carcinogens induce aberrant crypt foci (ACF) in the colons of F344 rats. F344 rats were provided with diets that contained putative risk factors for CRC: low calcium and low vitamin D, high iron, high fructose, and decreased light (UV) exposure or a control diet for 14 wk. The rats were then assessed with biochemical measures and by topological examination for evidence of colon abnormalities. Circulating ionized calcium was decreased from 2.85 to 1.69 mmol/L, and ACF were increased from 0.7 to 13.6 lesions/colon (both P < 0.001). Rats exposed to the multiple environmental conditions associated with colon cancer, developed ACF similar to the heterogeneous or ill-defined ACF in the human colon. Heterogeneous ACF are the most frequently seen in humans and are also seen in rats shortly after exposure to the non-genotoxic colon carcinogen, dextransulfate sodium. The rodent model could be used to assess the pathways from diet and environment to colon cancer and to provide guidance for clinical studies.  相似文献   
3.
Abstract

Cardiac troponins (cTn) are currently the standard of care for the diagnosis of acute coronary syndromes (ACS) in patients presenting to the emergency department (ED) with chest pain (CP). However, their plasma kinetics necessitate a prolonged ED stay or overnight hospital admission, especially in those presenting early after CP onset. Moreover, ruling out ACS in low-risk patients requires prolonged ED observation or overnight hospital admission to allow serial measurements of c-Tn, adding cost. Heart-type fatty acid-binding protein (H-FABP) is a novel marker of myocardial injury with putative advantages over cTn. Being present in abundance in the myocellular cytoplasm, it is released rapidly (<1?h) after the onset of myocardial injury and could potentially play an important role in both earlier diagnosis of high-risk patients presenting early after CP onset, as well as in risk-stratifying low-risk patients rapidly. Like cTn, H-FABP also has a potential role as a prognostic marker in other conditions where the myocardial injury occurs, such as acute congestive heart failure (CHF) and acute pulmonary embolism (PE). This review provides an overview of the evidence examining the role of H-FABP in early diagnosis and risk stratification of patients with CP and in non-ACS conditions associated with myocardial injury.
  • Key messages
  • Heart-type fatty acid-binding protein is a biomarker that is elevated early in myocardial injury

  • The routine use in the emergency department complements the use of troponins in ruling out acute coronary syndromes in patients presenting early with chest pain

  • It also is useful in risk stratifying patients with other conditions such as heart failure and acute pulmonary embolism.

  相似文献   
4.
腭隐裂患者头颅侧位X线片测量分析   总被引:2,自引:0,他引:2  
朱彤  马莲 《中华口腔医学杂志》2003,38(2):132-134,I007
目的 应用回顾性研究的方法对 50例腭隐裂患者X线片测量并与健康对照组对比分析 ,观察软腭在形态学、运动能力以及腭帆提肌附着位置等方面的特点 ,进一步研究腭隐裂患者腭咽闭合不全的原因 ,为其诊断提供依据。方法 腭隐裂患者 50例 (年龄 4~ 51岁 ,平均年龄 1 1 9岁 ,男性 2 0例 ,女性 30例 ,男∶女 =1∶1 5)。对术前头颅侧位定位X线片共 1 0 0张 (每例静止及发“i”音各 1张 )进行测量分析。结果 腭隐裂组的软腭相对长度较对照组短 ,患者的腭帆提肌附着点相对位置比对照组靠前 ,发音时软腭抬高角度较小 ,以上 3项指标经统计学分析 ,差异有显著性 (P <0 0 5)。两组间硬腭相对长度和发音时软腭伸长量的比较差异无显著性 (P >0 0 5)。结论 通过测量所得指标(包括软腭相对长度、腭帆提肌附着位置及发音时软腭抬高角度 )是诊断腭隐裂的重要指标  相似文献   
5.
INTRODUCTIONTwo strategies are available for prevention of early-onset group B streptococcal (GBS) sepsis – clinical risk factor-based screening and routine culture-based screening of pregnant women for GBS colonisation. In our hospital, we switched from the former to the latter approach in 2014.METHODSWe compared the incidence of early-onset GBS sepsis during 2001–2015 between infants born to pregnant women who were screened for GBS colonisation and those born to women who were not screened.RESULTSAmong 41,143 live births, there were nine cases of early-onset GBS sepsis. All infants with GBS sepsis were born to pregnant women who were not screened for GBS colonisation. The incidence of early-onset GBS sepsis among infants of women who were not screened was 0.41 per 1,000 live births (95% confidence interval [CI] 0.19–0.77) when compared to infants of women who were screened, for whom the sepsis incidence was zero per 1,000 live births (95% CI 0–0.19; p = 0.005).CONCLUSIONOur data suggests that routine culture-based screening of pregnant women for GBS colonisation is a better preventive strategy for early-onset GBS sepsis in neonates when compared to clinical risk factor-based screening.  相似文献   
6.
Objective: Atrial fibrillation (AF) brings a risk of thrombosis, requiring oral coagulation, and is associated with renal impairment. The two processes may be linked, as altered fibrin clot structure is present in end-stage renal failure. We hypothesised that progressively deteriorating renal function is linked to altered whole blood and fibrin clot properties and fibrinolysis. Methods: Thrombogenesis and fibrinolysis in 200 warfarinised AF patients was assessed by thromboelastography (TEG), a micro-plate assay (MPA) and the international normalized ratio (INR). Renal function was determined by creatinine clearance and two versions of the estimated glomerular filtration rate (eGFR). Results: Two TEG indices independently reflecting thrombogenesis were linked to creatinine clearance (p?p?p?p?p?=?0.001). The INR was unrelated to any renal function index, and the CHA2DS2VASc score was unrelated to any index. Conclusion: In warfarinised AF patients, renal function is linked to whole blood clot and fibrin clot formation, structure and dissolution, but has no effect on the INR.
  • Key messages
  • Despite oral anticoagulation, patients with atrial fibrillation (AF) still suffer from stroke and venous thromboembolism.

  • The effect of renal function in warfarinised patients with AF is unknown and may account for excess thrombosis and/or haemorrhage.

  • Using two different laboratory methods, our data point to an effect of renal function on clot structure and function that is independent of an effect of warfarin.

  相似文献   
7.
It has long been recognized from epidemiological studies that Greenland Eskimos have substantially reduced rates of acute myocardial infarction (MI) compared with Western controls. From these epidemiological observations, the benefits of fatty fish consumption have been explored in cell culture and animal studies, as well as randomized controlled trials investigating the cardioprotective effects of omega-3 fatty acids. Dietary omega-3 fatty acids seem to stabilize the myocardium electrically, resulting in reduced susceptibility to ventricular arrhythmias, thereby reducing the risk of sudden death. These fatty acids also have potent anti-inflammatory effects, and may also be antithrombotic and anti-atherogenic. Furthermore, the recent GISSI-Prevention study of 11 324 patients showed a marked decrease in risk of sudden cardiac death as well as a reduction in all-cause mortality in the group taking a highly purified form of omega-3 fatty acids, despite the use of other secondary prevention drugs, including beta-blockers and lipid-lowering therapy. The use of omega-3 fatty acids should be considered as part of a comprehensive secondary prevention strategy post-myocardial infarction.  相似文献   
8.
Incidence of inadvertent arterial puncture secondary to central venous catheter insertion is not common with an arterial puncture rate of<1%.This is due to the advancements and wide availability of ultrasound to guide its insertion.Formation of arteriovenous fistula after arterial puncture is an unexpected complication.Till date,only five cases(including this case)of acquired arteriovenous fistula formation has been described due to inadvertent common carotid puncture.The present case is a 26-year-old man sustained traumatic brain injuries,chest injuries and multiple bony fractures.During resuscitative phase,attempts at left central venous catheter via left internal jugular vein under ultrasound guidance resulted in inadvertent puncture into the left common carotid artery.Surgical neck exploration revealed that the catheter had punctured through the left internal jugular vein into the common carotid artery with formation of arteriovenous fistula.The catheter was removed successfully and common carotid artery was repaired.Postoperatively,the patient recovered and clinic visits revealed no neurological deficits.From our literature review,the safest method for removal is via endovascular and open surgical removal.The pull/push technique(direct removal with compression)is not recommended due to the high risk for stroke,bleeding and hematoma formation.  相似文献   
9.
Malaysia has one of the highest total numbers of COVID-19 infections amongst the Southeast Asian nations, which led to the enforcements of the Malaysian “Movement Control Order” to prohibit disease transmission. The overwhelming increasing amount of infections has led to a major strain on major healthcare services. This leads to shortages in hospital beds, ventilators and critical personnel protective equipment. This article focuses on the critical adaptations from a general surgery department in Malaysia which is part of a Malaysian tertiary hospital that treats COVID-19 cases. The core highlights of these strategies enforced during this pandemic are: (1) surgery ward and clinic decongestions; (2) deferment of elective surgeries; (3) restructuring of medical personnel work force; (4) utilization of online applications for tele-communication; (5) operating room (OR) adjustments and patient screening; and (6)continuing medical education and updating practices in context to COVID-19. These adaptations were important for the continuation of emergency surgery services, preventing transmission of COVID-19 amongst healthcare workers and optimization of medical personnel work force in times of a global pandemic. In addition, an early analysis on the impact of COVID-19 pandemic and lockdown measures in Malaysia towards the reduction in total number of elective/emergent/trauma surgeries performed is described in this article.  相似文献   
10.
OBJECTIVES: We sought to test the hypothesis that there is a relationship between inflammation and the prothrombotic state in atrial fibrillation (AF). BACKGROUND: Atrial fibrillation is associated with a prothrombotic or hypercoagulable state, which may contribute to an increased risk of stroke and thromboembolism. Inflammation may be involved in the pathogenesis of AF, but the role of inflammation in the pathophysiology of the prothrombotic state of AF has not been studied in detail, despite evidence of a link between inflammation and arterial atherothrombotic disorders. METHODS: We measured plasma indexes of inflammation (C-reactive protein [CRP] and interleukin-6 [IL-6]) and the prothrombotic state, including markers of platelet activation (soluble P-selectin), endothelial damage/dysfunction (von Willebrand factor), the coagulation cascade (tissue factor [TF], fibrinogen), and indexes of blood rheology (plasma viscosity, plasma fibrinogen, and hematocrit) in 106 patients with chronic AF and 41 healthy control subjects included in a cross-sectional analysis. RESULTS: Compared with controls, AF patients had higher levels of IL-6 (p = 0.034), CRP (p = 0.003), TF (p = 0.019), and plasma viscosity (p = 0.045). Plasma IL-6 levels were higher among AF patients at "high" risk of stroke (p = 0.003). After adjusting for potential confounding clinical variables (e.g., vascular disease), AF remained significantly associated with a raised logarithmic transformation (log) of TF (p = 0.04), but the relationships between AF and log IL-6, log CRP, and plasma viscosity became nonsignificant. Among AF patients, log TF (p < 0.001) and high stroke risk (p = 0.003) were independent associates of log IL-6 (adjusted r(2) = 0.443), whereas log fibrinogen (p < 0.001) and plasma viscosity (p = 0.04) were independent associates of log CRP (adjusted r(2) = 0.259). CONCLUSIONS: Increased plasma IL-6, CRP, and plasma viscosity support the case for the existence of an inflammatory state among "typical" populations with chronic AF. These indexes of inflammation are related to indexes of the prothrombotic state and may be related to the clinical variables of the patients (underlying vascular disease and co-morbidities), rather than simply to the presence of AF itself.  相似文献   
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