Background Though nitrates have been used in achalasia for a long time, the effectiveness of nitrates for achalasia is still controversial. Objectives To quantify short-term and long-term effects of nitrate therapy in patients with achalasia. Search strategy Trials were identified by searching the Cochrane Controlled Trials Register (Issue 4, 2001), MEDLINE (1966-2001), EMBASE (1980-2001), LILACS-Latin American and Caribbean health science literature (1982-2001) and CBM-Chinese Biomedical Database (1980-2000). Additionally, all references in the identified trials were checked for further relevant trials. Selection criteria All randomised controlled trials involving achalasia patients given any type of nitrates were included. Data collection amp; analysis Data were extracted By two independent observers based on the intention-to-treat principle. Odds ratios for the patients need to treat by invasive procedures, improvement of symptoms, LES pressure decrease, oesophageal emptying, and side effects were calculated. Numbers needed to treat (NNT) for avoiding invasive procedure, improvement of symptoms, oesophageal emptying, and numbers needed to harm (NNH) of side effects were also determined. Main results Two randomised cross-over studies were found, But no results are included. Due to the design of the studies and the method of reporting the results in the original paper it was not possible to extract the necessary information to examine any of the outcomes. Authors have been contacted to obtain this information. Reviewers’ conclusion We can conclude no implications for practice at this stage. Much more RCT data are needed to determine the effects of nitrates.
Objective To investigate the possible damaging effect of infrasound on ultrastructure and permeability of rats′blood-retinal barrier (BRB). Methods Twenty mature male rats, averagely divided into 5 groups according to the exposure duration, were exposed to infrasound at a 16 Hz frequency and 130 dB sound pressure level in a pressure chamber for 2 hours per day. After exposed for 0, 1 day, 7, 14, and 21 days respectively, ultrastructural changes of rats′ BRB were observed through injection of lanthanum (La) nitrate solution, which was used as a tracer to demonstrate the breakdown of the BRB.Results With prolonging the duration of infrasound exposure, BRB structure lesion, chondriosome tumefaction, endoplasmic reticulum expandedness, membrane disc damage, retinal pigment epithelial cells distortion and putrescence, karyotheca expandedness, and La leakage on each level of retina aggravated gradually.Conclusion Infrasound may cause the breakdown of BRB, and the lesions aggravated with prolonged infrasound exposure time. (Chin J Ocul Fundus Dis，2003，19：46-48)
ObjectivesTo systematically assess the efficacy and safety of nitrates for patients with chronic heart failure. MethodWe searched PubMed, EMbase, Web of Science, The Cochrane Library (Issue 1, 2016), CBM, CNKI, VIP, and WanFang Data to collect randomized controlled trials (RCTs) and cross-over studies about nitrates in the treatment of heart failure from inception to January 4th 2016. Two reviewers independently screened literature, extracted data and evaluated the risk of bias of included studies. Then, meta-analysis was performed by RevMan 5.3 software. ResultsTen trials were included involving 414 patients (195 patients in the nitrates group and 219 patients in the control group). The results of meta-analysis showed that, compared with the control group, the nitrates group could reduce arterial blood pressure (MD=-1.91, 95%CI -3.66 to -0.16, P=0.03), pulmonary wedge pressure vessels (PCWP) (MD=-2.00, 95%CI -3.84 to -0.15, P=0.03), increase cardiac index (CI) (MD=0.25, 95%CI 0.09 to 0.42, P=0.003), treadmill exercise time (MD=70.14, 95%CI 55.22 to 85.05, P < 0.000 01); but easily emerge side effects (OR=5.21, 95%CI 2.60 to 10.41, P < 0.000 01). ConclusionCurrent evidence indicates that nitrates treatment could improve the hemodynamic effect, enhance cardiac output and increase exercise tolerance in patients with heart failure.