Pretreatment circadian period in free-running blind people may predict the phase angle of entrainment to melatonin.

To date, we have entrained (synchronized) eight totally blind people with free-running circadian rhythms to a nightly dose of 10 mg of melatonin. Each person entrained at a different phase angle of entrainment (PAE), which is the interval in hours between the time of the melatonin dose and the time of the endogenous melatonin onset. When the PAE was plotted against the pretreatment free-running (i.e. slightly different than 24.0 h) circadian period (tau), the fitted regression line revealed a significant correlation, which is consistent with previous findings on light entrainment of rest-activity rhythms in free-running rodents [Pittendrigh and Daan, J. Comp. Physiol., 106 (1976) 291-331].     

Screw osteosynthesis of displaced fractures of the radial condyle of the humerus in childhood. A long-term prospective study

Summary Pseudoarthrosis and cubitus valgus as main complications following displaced fractures of the radial condyle in children can be prevented by open reduction and fixation by K wires. However, delayed union and stimulation of the radial physis with condylar overgrowth and varisation of the elbow as well as fishtail deformities of the distal end of the humerus are reported nevertheless. To prevent those growth disturbances all primary and secondary (4-day X-ray control) displaced fractures of the radial condyle, i. e. those with a central gap of more than 2 mm, were prospectively treated by open reduction and osteosynthesis with a metaphyseal lag screw beginning 1974. Sixty-six patients (41 boys, 25 girls) with an average follow-up of 10 years (2–22 years) sustained 28 primary and 6 secondary displaced fractures. In 5 cases a K wire fixation was performed in view of the smallness of the fragment. Two children with conservative treatment following overlooked displaced fractures showed condylar overgrowth and varisation of the elbow. Screw osteosynthesis led to symmetric elbow angles and function in all cases, whereas fishtail deformities could be observed in 8 of 27 children, probably as a consequence of the remaining central fracture instability. Conclusion: Open reduction and osteosynthesis with a metaphyseal lag screw prevents condylar overgrowth in displaced fractures of the radial condyle by guaranteeing fracture healing in anatomic position within 3–4 weeks. However, fishtail deformity can not be prevented by metaphyseal compression only.      

Electrogastrography: a document prepared by the gastric section of the American Motility Society Clinical GI Motility Testing Task Force

The objective of this document is to present the consensus opinion of the American Motility Society Clinical GI Motility Testing Task Force on the performance and clinical utility of electrogastrography (EGG). EGG is a non-invasive means of recording human gastric myoelectrical activity or slow waves from cutaneous leads placed over the stomach. In healthy volunteers, EGG tracings exhibit sinusoidal waveforms with a predominant frequency of 3 cycles per minute (cpm). Clinical studies have shown good correlation of these cutaneous recordings with those acquired from serosally implanted electrodes. The amplitude of the EGG waveform increases with ingestion of caloric or non-caloric meals. Some patients with nausea, vomiting, or other dyspeptic symptoms exhibit EGG rhythm disturbances or blunting of meal-evoked EGG signal amplitude increases. These abnormalities correlate to some degree with delayed gastric emptying of solids. In selected patients, EGG may be complementary to gastric emptying testing. To date, no therapies have convincingly demonstrated in controlled studies that correcting abnormalities detected by EGG improves upper gastrointestinal symptoms. Proposed clinical indications for performance of EGG in patients with unexplained nausea, vomiting and dyspeptic symptoms must be validated by prospective controlled investigations.     

Molecular dosimetry in rat urine of aflatoxin-N7-guanine and other aflatoxin metabolites by multiple monoclonal antibody affinity chromatography and immunoaffinity/high performance liquid chromatography.

The development of molecular dosimetry methods will simplify the identification of people at high risk for cancer. A combined monoclonal antibody immunoaffinity chromatography/high performance liquid chromatography method has been devised to isolate and quantify aflatoxin-DNA adducts and other metabolites in rat urine samples. We report the production of 11 different monoclonal antibodies recognizing aflatoxin B1, aflatoxin Q1, aflatoxin G1, aflatoxicol, and aflatoxin M1 and the application of these antibodies to a multiple monoclonal antibody affinity chromatography technique. Using the multiple monoclonal antibody affinity column with rat urines obtained from dosed animals, between 90 and 95% of total aflatoxin metabolites can be bound to the column and isolated. Analytical immunoaffinity chromatography/high performance liquid chromatography analysis of these isolated aflatoxins reveals that more than 55% of the aflatoxins in rat urine are aflatoxin-dihydrodiol, aflatoxin-N7-guanine, aflatoxin Q1, aflatoxin M1, aflatoxin P1, and aflatoxin B1, accounting for 1.5, 9.6, 1.8, 34.5, 8.0, and 1.0% of the total aflatoxins, respectively. Further, a perchloric acid digestion of the aflatoxin-N7-guanine peak was used to confirm its identity by its conversion to guanine. The measurement of aflatoxin-N7-guanine excretion in rat urine was examined to assess its utility as a marker of DNA adduct formation in the liver, and a dose-dependent excretion in urine was found with a correlation coefficient of 0.99. A comparison of the dose-dependent residual levels of aflatoxin binding to liver DNA with the amount of aflatoxin-N7-guanine excreted in urine showed a correlation coefficient of 0.98. Besides the nucleic acid adduct excretion data, aflatoxin M1 and aflatoxin P1 were evaluated as molecular dosimeters in the urine. Aflatoxin M1 was found to be an excellent marker, whereas no linear relationship between dose and aflatoxin P1 excretion in urine was found.     

北美荷斯坦牛胚胎移植现状与20年前之比较

本文调查总结了北美不同区域中4种商业化胚胎移植程序在过去20年以来荷斯坦成母牛及青年母牛胚胎移植实施及其结果情况。随着时间的推移,在一种程序中平均每次冲胚获得的胚胎数下降(P<0.05),但是其它三种程序却无此现象。针对胚胎移植程序中所用的不同类型母牛,不同超排处理次数及所使用不同品牌促性腺激素等复杂因素进行了分析,数据显示,将胚胎移植给荷斯坦青年母牛比移植给泌乳牛的妊娠率(P<0.001)高。目前还不清楚妊娠率下降是否与移植方法从手术法改变到非手术法有关。针对两个程序的妊娠率进行了分析比较,其中一个程序在采用非手术法移植时受胎率下降(P<0.001),然而另一个却没变化。所有胚胎移植程序中最大的变化之一就是从供体收集到的胚胎中有50%以上在采集后作冷冻处理,然而在20年前大部分胚胎都作鲜胚移植。     

Posterior tibial tendon dysfunction and MR imaging in rheumatoid arthritis

We present the case of a patient with long-standing rheumatoid arthritis and an acute onset of total dysfunction of the posterior tibial tendon. On MRI, a rupture of the tendon was apparent. Intraoperatively, however, massive tenosynovitis with stricture of the tendon was identified as the cause of posterior tibial tendon dysfunction. This case illustrates a pitfall in MRI imaging with potential diagnostic and therapeutic consequences.