Nitrate administration to enhance the detection of myocardial viability by technetium-99m tetrofosmin single-photon emission tomography

A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with^99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent²⁰¹T1 rest-injection and^99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of^99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline^99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in^99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on²⁰¹Tl studies, but 20 segments that were non-viable on^99mTc-tetrofosmin. studies were viable on²⁰¹Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on^99mTc-tetrofosmin studies. Overall agreement between^99mTc-tetrofosmin with nitrates and²⁰¹Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with^99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies.     

The results of the interference of nitrates and vitamin E in the metabolism in the connective tissue of rat''s liver

We examined 72 female Wistar rats which were divided into 6 groups. The animals were administered sodium nitrate (V), vitamin E or both compounds at the same time. In order to estimate the interference of nitrates in the presence of vitamin E with the metabolism of rat's liver, we determined the composition and the amount of glycosoaminoglycans (GAGs). It was stated that the total amount of GAGs increased in livers of all rats. Basing on all fractions of the examined GAGs it was determined that the most significant differences between individual groups appeared in the amount of heparane sulphate (HS). The results obtained confirmed the fact of the changes taking place in the picture of liver GAGs in the process of ageing of the examined animals. The results obtained, however, allowed to state the normalising influence of vitamin E on the quantitative composition of GAGs of rats which drank nitrates.     

Role of Antiischemic Agents in the Management of Non‐ST Elevation Acute Coronary Syndrome (NSTE‐ACS)

Non‐ST elevation acute coronary syndrome (NSTE‐ACS) is the commonest acute presentation of coronary artery disease (CAD). Mortality and morbidity of the condition has improved substantially over the last few decades as a result of the cumulative effect of multiple interventions acting via different mechanisms. Despite a significant increase in the rate of coronary intervention, medical therapy continues to retain a central role in the treatment of NSTE‐ACS particularly in frail patients where revascularization is inappropriate or when it is incomplete. Several antiischemic agents have been used in the treatment of the condition. Beta blockers are often the first‐line choice with calcium channel blockers and nitrates being used as an alternative when beta blockers are contraindicated, or as an addition to achieve optimal symptom control. Newer agents, such as nicorandil, ivabradine, and ranolazine have also been used in refractory cases. Although most of these agents have been extensively studied in large randomized controlled trials in patients with stable CAD or ST elevation acute coronary syndrome (STE‐ACS), the evidence supporting their use in NSTE‐ACS is less clear cut. In this article, we review various drugs available for controlling ischemia and the latest evidence in support of their use in NSTE‐ACS.     

离子色谱法同时测定生活饮用水中4种阴离子

目的用离子色谱法同时测定生活饮用水中的氟化物、氯化物、硝酸盐、硫酸盐4种阴离子。方法选用IC6000离子色谱仪,SI-52E SHODEX阴离子分离柱,Na2CO3淋洗液,水样过滤后直接进样,保留时间定性,峰面积定量。结果本方法各物质的检出限分别为氟化物0.08 mg/L、氯化物0.08 mg/L、硝酸盐0.04 mg/L、硫酸盐0.15 mg/L,相对标准偏差均在1.17%以下,回收率在98.9%~101.1%之间。结论用离子色谱同时测定饮用水中4种阴离子的方法,操作简便、灵敏度高、重现性好,可满足GB 5749-2006生活饮用水卫生标准的相关要求。     

门诊应用硝酸酯类药物病人的护理

目的探讨门诊应用硝酸酯类药物病人的护理,提高用药安全性。方法对门诊应用硝酸酯类药物的病人进行用药前评估,用药中加强观察,整个用药过程贯穿健康教育。结果患者对硝酸酯类药物的认知程度有了显著提高,能积极配合用药,提高了用药安全性。结论针对门诊应用硝酸酯类药物病人施行全过程护理,对提高用药安全性具有重要意义。     

益心舒胶囊联合化学药治疗气阴两虚型稳定型心绞痛230例临床观察

目的:观察益心舒胶囊联合化学药治疗气阴两虚型稳定型心绞痛的临床疗效。方法:将230例气阴两虚型稳定型心绞痛患者以随机数字表法分为2组,对照组92例,给予硝酸酯类药、β受体阻断剂、他汀类药等常规治疗;治疗组138例,在对照组常规用药的基础上加用益心舒胶囊,1次3粒,1日3次,4周为1个疗程。1个疗程结束后进行疗效评定。结果:治疗组与对照组对控制心绞痛症状及改善心电图(ECG)变化均有较好疗效,但组间比较无显著差异(P>0.05);症状控制方面,治疗组对心悸、自汗、气短、乏力等临床症状有明显的改善作用,与对照组比较有显著差异(P<0.05或P<0.01);血脂控制方面,在他汀类药的配合下,治疗组能明显升高高密度脂蛋白(HDL-C)、降低低密度脂蛋白(LDL-C),与对照组比较差异有统计学意义(P<0.05或P<0.01)。结论:益心舒胶囊联合硝酸酯类药、β受体阻断剂、他汀类药治疗稳定型心绞痛,可提高临床疗效,改善症状,增强调节血脂的功能。     

The multitude and diversity of environmental carcinogens

We have recently proposed that lifestyle-related factors, screening and aging cannot fully account for the present overall growing incidence of cancer. In order to propose the concept that in addition to lifestyle related factors, exogenous environmental factors may play a more important role in carcinogenesis than it is expected, and may therefore account for the growing incidence of cancer, we overview herein environmental factors, rated as certainly or potentially carcinogenic by the International Agency for Research on Cancer (IARC). We thus analyze the carcinogenic effect of microorganisms (including viruses), radiations (including radioactivity, UV and pulsed electromagnetic fields) and xenochemicals. Chemicals related to environmental pollution appear to be of critical importance, since they can induce occupational cancers as well as other cancers. Of major concerns are: outdoor air pollution by carbon particles associated with polycyclic aromatic hydrocarbons; indoor air pollution by environmental tobacco smoke, formaldehyde and volatile organic compounds such as benzene and 1,3 butadiene, which may particularly affect children, and food pollution by food additives and by carcinogenic contaminants such as nitrates, pesticides, dioxins and other organochlorines. In addition, carcinogenic metals and metalloids, pharmaceutical medicines and cosmetics may be involved. Although the risk fraction attributable to environmental factors is still unknown, this long list of carcinogenic and especially mutagenic factors supports our working hypothesis according to which numerous cancers may in fact be caused by the recent modification of our environment.     

Risk factors and prevention of cardiotoxicity induced by 5-fluorouracil or capecitabine

Aim: 5-Fluorouracil (5-FU) and its prodrug capecitabine are cardiotoxic. This retrospective study aimed to identify risk factors and to give practical measures to make such chemotherapy feasible if cardiotoxicity occur. Method: Review of cardiotoxicity among 668 patients treated with 5-FU or capecitabine for gastrointestinal cancers. Results: Cardiotoxicity occurred in 29 cases (4.3%). The number of cases according to cardiotoxicity CTC grades 2–4 for patients with and without pre-existing cardiovascular disease were none, 10, and 2 cases, and 3, 14, and no cases, respectively (P=0.16). In three patients intercurrent decrease of renal clearances to <30, 48 and 71 ml min^-1 led to markedly increased cardiotoxicity. Chemotherapy dose reduction to 70 or 50%, either alone or in addition to antiangina medication prevented cardiotoxicity during subsequent chemotherapy in nine (60%) and three (20%) cases out of 15 assessable patients (P=0.001), respectively. To abolish symptoms of cardiotoxicity, sublingual nitroglycerine was efficient for 15 patients and inefficient for two (P=0.001). Conclusion: Cardiac and renal co-morbidity are risk factors for 5-FU induced cardiotoxicity. In this situation, rechallenge with modified 5-FU-based chemotherapy regimen supported by symptomatic medical treatment is feasible.     

Effect of nitrites and nitrates on irrigation and secretion of gastric mucosa in rat

Summary An aspect of the vasomotor effect of nitrites and nitrates was studied by investigating the influence of these substances on the mucosal blood flow and hence on gastric secretion in the rat. Firstly, point measurements were obtained using an aminopyrine clearance technique after intravenous nitrite and nitrate treatment. Then with an appreciably different technique (¹⁴C-aniline clearance on perfused stomach) the kinetics of the phenomenon were followed after, firstly, intravenous administration of the two agents and secondly their intragastric administration. It is interesting to note that nitrites and nitrates are active to differing degrees and present opposing effects: nitrites decrease whereas nitrates globally enhance the factors under consideration (gastric mucosal blood flow, gastric juice volume, acid and pepsin output). The strong action of nitrites, even though retarded, persists throughout intragastric perfusion. However, intravenously administered, nitrates have a more transitory effect and cause no modification on intragastric administration. The flow rate-gastric parameter correlations are significant in all cases and show modifications of the aqueous compartments of the body.