Clinical observation of postoperative visual perceptual training in children with intermittent exotropia on the recovery of visual function at all levels / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the role of visual perception training on the recovery of visual function at all levels and the improvement of perceptual eye position in children with intermittent exotropia(IXT).METHODS: Prospective clinical study. A total of 74 patients with IXT who received corrective surgery for strabismus in the Ophthalmology Department of the First People's Hospital of Lanzhou City from January to June 2022 were collected and followed up for 3mo. The patients were randomly divided into 2 groups at 1d after surgery: 35 patients in the training group received binocular visual perception training, and 39 patients in the control group did not receive visual training. The changes of visual function and perceived eye position at all levels were observed at 1d and 3mo after operation.RESULTS: There were 24 patients(69%)with simultaneous perception in the training group at 1d after surgery and 34 patients(97%)with recovered visual function at 3mo after surgery, which was significantly higher than 1d after surgery(P=0.002). Furthermore, there were 22 cases(56%)of fusion function in the control group at 3mo after surgery, 13 cases(33%)of far stereopsis, 20 cases(51%)of dynamic stereopsis and 17 cases(44%)of static fine stereopsis. In the training group, there were 31 cases(89%)of fusion function, 25 cases(71%)of far stereopsis, 30 cases(86%)of dynamic stereopsis and 27 cases(77%)of static fine stereopsis, which were significantly higher than those in the control group(all P<0.05). The degree of perceived eye displacement in the training group decreased more significantly than that in the control group(all P<0.05).CONCLUSION: Postoperative visual perceptual training in children with IXT can promote recovery of visual function at all levels, improve perceptual eye position and enhance the control of eye position at the perceptual level of the brain.

Research progress of visual perception training on postoperative reconstruction of binocular vision in patients with intermittent exotropia / 国际眼科杂志(Guoji Yanke Zazhi)

Intermittent exotropia(IXT)is a common ophthalmic disease with high incidence, variable deviation, and varying degrees of impaired binocular visual function. The defect of binocular visual function is related to the changes of visual cortex. IXT involves the functional changes of many brain regions, including the cortical areas related to binocular fusion. After correcting the eye position, the abnormal changes of cerebral cortex still exist in some patients with IXT, and the recovery of binocular vision is still difficult. In order to solve these problems, visual perception training is gradually applied to the postoperative reconstruction of binocular visual function in patients with IXT. Visual perception training repairs the visual cortex from the brain level, improving the ability of the visual cortex to process information by constantly stimulating the visual center, thus repairing the visual central function, so that patients can obtain good binocular visual function, stabilize the eye position and reduce recurrence. This article reviews the mechanism of binocular visual impairment and the role of visual perception training in the treatment of IXT. It is hoped to provide more evidence for visual perception training to reconstruct postoperative binocular visual function and reduce the recurrence rate in patients with IXT.

Distribution of deltamethrin in acute poisoned rats / 法医学杂志

OBJECTIVE@#To establish an animal model in acute poisoned rat by deltamethrin and an analysis method for determination of deltamethrin by gas chromatography-electron capture detector (GC-ECD) and to study the distribution of deltamethrin in rats in order to provide the references for forensic medicine identification about such cases.@*METHODS@#Rats were administered with deltamethrin of different doses(512 and 1,024 mg/kg) and killed 1.5 h later to be dissected rapidly for tissues (blood, hearts, livers, lungs, kidneys and brains etc.). Samples were dehydrated by anhydrous sodium sulfate and extracted with petroleum ether and acetone (V:V=4:1). The level of deltamethrin was determined by GC-ECD.@*RESULTS@#There was a good separate between deltamethrin and endogenous impurities. The limit of quantification for deltamethrin in blood and liver were 0.1 microg/mL and 0.1 microg/g (S/N> or =10), respectively. The recovery rate of deltamethrin in blood was 91.55%-134.37% and both inter-day and intra-day precisions were less than 5.67%. The distribution of deltamethrin in poisoned rats with 512 mg/kg was as follow: lungs > livers > hearts > kidneys > blood > brains and with 1 024 mg/kg dose was lungs > blood > hearts > kidneys > brains > livers (P<0.05).@*CONCLUSION@#The GC-ECD method is sensitive for determination of deltamethrin. The distribution of deltamethrin in rats has a dose-dependent manner. The study suggests that samples of blood, hearts, livers, lungs, kidneys and brains are suitable for deltamethrin poisoned analysis.

Stability of estazolam in dog tissues preserved in formaldehyde solution / 法医学杂志

OBJECTIVE@#To investigate the stability of estazolam in biological samples preserved in formaldehyde solution.@*METHODS@#The dog was given intragastric administration of estazolam with a dose of 37.6 mg/kg and killed 2 h later. Heart, liver, kidney and brain of the dog were cut up into 1 g and preserved in 4% formaldehyde solution respectively. The content of estazolam in biological samples and formaldehyde solution were analyzed by HPLC at different times.@*RESULTS@#The content of estazolam in heart, liver, kidney and brain or in formaldehyde solution reduced gradually followed with the extention of preservation time. At the 63rd day, estazolam content in four tissues were 0.8%, 1.7%, 1.0% and 2.2% of the original content respectively.@*CONCLUSION@#Estazolam in tissues can diffuse into formaldehyde solution and decomposed quickly, so biological samples contained estazolam should not be preserved in formaldehyde solution.

Toxicokinetics of ketamine in rabbits / 法医学杂志

OBJECTIVE@#To investigate the toxicokinetics profiles of ketamine and its main metabolite norketamine in rabbits.@*METHODS@#The rabbits were administered orally the hydrochloride of ketamine with a dose of 0.15 g/kg. The serum and urine samples were collected before administration and at different time points after drug administration. The concentrations of ketamine and norketamine were determined by GC-NPD and GC-MS. Compartment model and toxicokinetics parameters were simulated and calculated by WinNorLin program. Changes of important vital signs of rabbits were recorded during the experiment.@*RESULTS@#The mean serum concentration-time profile of ketamine and norketamine were fitted to a two-compartment open model with first order kinetics. The kinetic equation of ketamine and norketamine were p(t) = 121.760 e(-0.0025t) +0.980 e(-0.002t) +4.579 e(-0.021 t) and p(t) = 640.919 e(-0.03 t) +1.023 e(-0.001 t) +9.784 e (-0.031 t), respectively. The peak time and the peak concentration of ketamine in serum were (40.950 +/- 12.098) min and (9.015 +/- 1.344) microg/mL, respectively. The elimination half-time of ketamine in rabbits was (430.370 +/- 28.436) min. The serum and urine showed a middle relation in concentrations of ketamine during 30-240 min after drug administration. After oral administration ketamine to rabbits, the toxic symptom on the rabbits occurred at 30 min and disappeared after 120 min.@*CONCLUSION@#The toxicokinetics parameters and kinetic equation of ketamine and norketamine in rabbits may provide the theoretical basis for forensic identification of reasonable specimen collection and inferring the time of oral administration ketamine from the ketamine concentration in serum.

Effect of temperature and time on stability of ketamine in biological samples / 法医学杂志

OBJECTIVE@#The stability of ketamine in biological samples was studied under different storage temperature and time.@*METHODS@#The rabbits were given intragastric administration of ketamine with a dose of 150 mg/kg and were sacrificed after 30 minutes. Blood, liver, kidney and brain of the rabbits were stored at room temperature (between 18 degrees C and 24 degrees C) and -20 degrees C. The specimens were analyzed at different times by GC-MS and GC-NPD.@*RESULTS@#At -20 degrees C, the concentration of ketamine decreased in all of samples (P < 0.05) within 30 days. The concentration of ketamine increased in all of samples stored at room temperature after 5 days(P < 0.05).@*CONCLUSION@#The stability of ketamine in biological samples stored at -20 degrees C was better than that at room temperature. The samples suspected containing ketamine should be stored at -20 degrees C and should be tested as soon as possible.

Analysis on the abused drugs in saliva and correlation of saliva drugs concentrations with blood concentrations / 法医学杂志

Saliva is an easily collected body fluid and has simple composition. Some drugs concentrations in saliva can reflect their blood level. This paper analyzes the mechanisms of drug transfer from blood into saliva and the influencing factors, reviews the methods of sample collection, preparation, analysis of the abused drugs in saliva, and the relationship between abused drugs content in saliva and in blood. We believe that saliva is a valuable sample in clinic and forensic medicine. It is important in forensic science field to estimate abused drugs concentrations in blood by via their saliva concentrations.