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1.
Amiodarone is the most potent antiarrhythmic drug available and is commonly prescribed to treat and prevent not only life-threatening ventricular arrhythmias but also atrial fibrillation (AF). The latest European Society of Cardiology AF guidelines state that amiodarone is recommended for long-term rhythm control in all AF patients but that other antiarrhythmic drugs should be considered first whenever possible, due to its extracardiac toxicity. In patients without significant or with only minimal structural heart disease, amiodarone is not listed as a possibility in their therapeutic scheme. Still, amiodarone is widely and liberally used, and is the most prescribed antiarrhythmic drug for patients with AF despite its high toxicity profile. Non-cardiovascular death was more frequent with amiodarone treatment than with a rate control strategy in AFFIRM, while meta-analyses suggest an association between amiodarone use in patients without structural heart disease and increased non-cardiovascular mortality. Severe or even fatal outcomes due to amiodarone may occur years after treatment initiation and are often not acknowledged by the prescribing physician, who may no longer be following the patient. The lack of widely accepted diagnostic criteria and symptom definitions may lead to underestimation of the incidence of severe side effects and of its toxicity. Unlike the underestimated risk of toxicity with amiodarone, severe complications associated with catheter ablation are usually directly ascribed to the treatment even by non-medical personnel, possibly resulting in overestimation of risks. This brief review will address the issue of amiodarone overuse and the frequent underestimation of its toxicity, while suggesting scenarios in which its use is entirely reasonable, and compare it with catheter ablation.  相似文献   
2.
Continuous utero-placental circulation, and patent umbilical blood vessels ensure an uninterrupted transfer of oxygen and nutrients to the fetus as well as clearance of metabolic waste products. The onset of labour characterized by progressive and strong uterine contractions poses a threat to fetal oxygenation as a result of collapsing the spiral arterioles traversing the myometrium to supply the placental bed, and repetitive compression of the blood vessels within the umbilical cord. Human fetuses are equipped with compensatory mechanisms to cope with transient interruptions of blood supply during labour. The ability to compensate may be blunted in cases of poor fetal reserves, increased metabolic demand (macrosomia or maternal fever), and due to non-hypoxic pathways (e.g. chorioamniontis or fetal hypovolumia-hypotension syndrome). Intrapartum fetal surveillance involves prompt recognition of the features that signal the onset of fetal decompensation on the cardiotocograph (CTG) to ensure a timely intervention to avoid hypoxic-ischaemic encephalopathy (HIE) or perinatal deaths. This article summarises a ‘physiological approach’ to the interpretation of the CTG which, in places, conflicts with other current UK guidance.  相似文献   
3.
Take the lead     
《Survey of ophthalmology》2023,68(5):1006-1010
A 23-year-old previously healthy woman presented with headache, generalized seizures, ataxia, encephalopathy, abdominal pain, nausea, and vomiting culminating in a 40-pound weight loss. A contrasted magnetic resonance imaging scan of the brain showed T2/FLAIR hyperintensities in the sulci of the occipital and parietal lobes, a punctate focus of restricted diffusion along the inferior aspect of the left caudate head and an empty sella. A lumbar puncture showed an opening pressure of 55 cm H2O, and kidney, ureter, and bladder X ray showed a radiopaque particle in the colon. Serum lead level was 85 mcg/dL (< 3.5). Blood smear showed foreign bodies identified as lead particles in the blood with basophilic stippling of RBCs. She was treated with chelation therapy and bowel irrigation and eventually recovered. Further investigation indicated that she was being slowly poisoned by her husband, a chiropractor who had access to lead.  相似文献   
4.
Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity.  相似文献   
5.
In the present study, we aimed to observe the effects of ethanol extract of Oxalis corniculata L. on bleeding time (BT) and coagulation time (CT) and determine its acute toxicity in mice. Firstly, the ethanol extract of O. corniculata was administered to 40 mice, which were randomly divided into the normal control group, Yunnan Baiyao control group, low-dose group, and high-dose group. The low-dose (0.6 g/kg) and high-dose (1.2 g/kg) groups received ethanol extract of O. corniculata by gavage, and the BT and CT of the mice were measured by the slide method and tail clipping method, respectively. Secondly, the median lethal dose method was used with 50 mice to observe the physiological state, poisoning reaction, and death of the mice after intragastric administration. Finally, on the 14th day of the experiment, a necropsy was performed to observe any abnormality of the organs. In conclusion, in the coagulation and hemostasis tests, there were no statistical differences between the groups (P > 0.05), while there was a significant dose-response relationship, and the BT and CT were significantly shorter than those of the negative control group, which were comparable to the Yunnan Baiyao control group. Moreover, in the acute toxicity test, the median lethal dose of ethanol extract of O. corniculata was 6.0291 g/kg, with a 95% confidence interval of 5.3065–6.7829 mg/kg.  相似文献   
6.
IntroductionSelective internal radiation therapy (SIRT) is a potential treatment of primary renal cell carcinoma (RCC) deemed unsuitable for conventional therapy. RESIRT is the first-in-human study to evaluate safety and feasibility of SIRT for primary RCC.Patients and MethodsPatients with RCC, unsuitable for, or who declined conventional therapy, were eligible. A single transfemoral micro-catheter administration of yttrium-90 (Y-90) resin microspheres (SIR-Spheres) was delivered super selectively via the renal artery to the tumour at intended radiation doses of 75, 100, 150, 200, 300 Gy and a final cohort with a procedural endpoint of “imminent stasis,” in a dose-escalation design. Post-SIRT follow-up was 12 months. Study endpoints included safety and toxicity 30-days and 12-months post-SIRT and tumour response (RECIST v1.1).ResultsIn total, 21 patients were enrolled, mean (SD) age was 75 (9.3) years, WHO performance status was 0 in 81%, 12 (57%) had stage 3 chronic kidney disease, and 7 (33%) had prior contralateral nephrectomy. Overall, 71% of patients completed 12 months of follow-up. Intended doses were delivered without any dose-limiting toxicity. Seventeen out of 21 (81%) patients experienced an adverse event (AE) from any cause within 30 days post-SIRT; all SIRT-related AEs were grade 1 to 2. Best overall tumour responses were partial response 1/21 (4.8%), stable disease 19/21 (90.5%) and progressive disease 1/21 (4.8%).ConclusionThis study demonstrated good tolerability of SIRT at all dose levels including “imminent stasis” in treating primary tumours in RCC patients otherwise unsuitable for conventional therapy. SIRT with Y-90 resin microspheres may be a feasible treatment option for RCC.  相似文献   
7.
BackgroundCabozantinib showed efficacy and manageable toxicity in patients with metastatic renal cell carcinoma (mRCC). In this study we aimed to describe the safety and to collect evidence on the potential efficacy of cabozantinib in mRCC patients with brain metastases (BM) in a real-world experience.Materials and MethodsWe retrospectively collected data of patients treated with cabozantinib within the Italian Managed Access Program. Patients were selected for the presence of BM before the start of treatment and for at least 1 previous tyrosine kinase inhibitor (TKI) treatment regimen for metastatic disease. Safety data were reported, and overall response rate (ORR), brain-specific response, progression-free survival (PFS), and median overall survival (OS) were analyzed.ResultsOverall, 12 patients treated with cabozantinib were evaluated. Any grade adverse events (AEs) accounted for 92%, Grade 3/4 AEs rated at 36% with no major neurological side effects. The most common AEs included hypertension (33%), fatigue (24%), aminotransferase elevation (25%), hypothyroidism (16%), and gastrointestinal toxicity (16%). The ORR was 50% with a disease control rate of 75%. All 5 patients treated with a combined systemic and brain-directed approach obtained intracranial disease control, without increased toxicity. Median PFS and median OS were 5.8 and 8.8 months, respectively. Comparable safety and tolerability results for other TKI regimens were reported from the literature.ConclusionCabozantinib showed safety, acceptable tolerability, and promising antitumor activity in a population of mRCC patients with BM from a real-world experience. A combined modality approach for renal cell carcinoma with BM, whenever feasible, could be recommended to improve oncological outcomes.  相似文献   
8.
Hyperprogressive disease (HPD) is a concerning paradoxical acceleration of cancer growth induced by immune drugs. The lack of standard radiological criteria makes its study challenging. We reviewed the literature and compared the main criteria for HPD proposed by Ferté, Le Tourneau, Garralda and Caramella to address this relevant unmet need in Immune-oncology.Among 182 consecutive patients with advanced cancer treated with immunotherapy in early-phase clinical trials, 71 with progressive disease at the first evaluation were eligible. HPD patients were studied regarding tumor growth dynamics and clinical impact.HPD occurred in 17 (23.9%), 17 (23.9%), 23 (32.4%) and 6 (8.4%) patients, as defined by Ferté, Le Tourneau, Garralda and Caramella, respectively. The strongest association was found between the Ferté and Le Tourneau criteria (Kappa = 0.61), and the Jaccard similarity index varied from 55% (Ferté and Le Tourneau) to 21% (Le Tourneau and Caramella). The Ferté and Le Tourneau criteria showed statistically significant differences between pre-baseline and post-baseline tumor growth rate in patients with HPD, which could not be confirmed with the Caramella and Garralda criteria. Significant differences in progression-free survival were observed between non-hyperprogressors and hyperprogressors, with all criteria. The proportion of patients that could not receive additional lines of therapy was higher in the HPD group.HPD is an immunotherapy-related acceleration of tumor growth kinetics, with a consequent negative clinical impact. Pre-baseline CT scans and tumor growth rate evaluations are required to identify HPD. Our analysis favors the use of the Le Tourneau method, as it captures adequately the HPD phenomenon and is more convenient to use.  相似文献   
9.
Most radiogenomics studies investigate how genetic variation can help to explain the differences in early and late radiotherapy toxicity between individuals. The field of radiogenomics in photon beam therapy has grown rapidly in recent years, carving out a unique translational discipline, which has progressed from candidate gene studies to larger scale genome-wide association studies, meta-analyses and now prospective validation studies. Genotyping is increasingly sophisticated and affordable, and whole-genome sequencing may soon become readily available as a diagnostic tool in the clinic. The ultimate aim of radiogenomics research is to tailor treatment to the individual with a test based on a combination of treatment, clinical and genetic factors. This personalisation would allow the greatest tumour control while minimising acute and long-term toxicity. Here we discuss the evolution of the field of radiogenomics with reference to the most recent developments and challenges.  相似文献   
10.
木鳖子是一味传统的有毒中药,始载于北宋《开宝本草》,具有消肿散结,攻毒疗疮的功效,用于治疗疮疡肿毒,乳痈,秃疮等。主要分布在广西、广东等中国南方地区,泰国、越南等东南亚国家也有分布。目前研究表明从木鳖子中提取分离得到的化学成分丰富,主要包括萜类、甾醇类、挥发油类、脂肪酸类等成分。其中已鉴定的萜类化合物30种、挥发油成分102种、植物甾醇6种和脂肪酸类19种。毒理学研究表明,木鳖子水提物及醇提物均含有一定的毒性,毒性随着含油量的增大呈现降低趋势,目前文献报道的主要有毒成分是木鳖子素和木鳖子皂苷类。药理学研究表明,木鳖子除了具有基于传统功效的抗癌、抗炎、抗菌等药理作用外,还具有抗溃疡、抗氧化、调节免疫等多种药理作用。近几年对木鳖子的研究报道不断增多,通过查找中国知网,万方,Pub Med,Web of Science等数据库1964-2019年的国内外相关文献,对木鳖子化学成分,药理作用,毒理研究等方面进行归纳总结,为今后对木鳖子的深入研究应用提供参考。  相似文献   
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