Comparison of detection success rate of different kinds of near-infrared spectrum non-invasive hemoglobin monitors in high-altitude environments / 中华麻醉学杂志

Objective:To compare the detection success rates (DSRs) of different kinds of near-infrared spectrum non-invasive hemoglobin monitors in high-altitude environments.Methods:One hundred and forty-four healthy volunteers of either sex, aged 18-50 yr, were assigned to one of 3 groups using a random number table method: simulated high-altitude 3 500 meter group ( n=35), 4 000 meter group ( n=55) and 4 500 meter group ( n=54). Hemoglobin was detected by Radical-7, NW-9002SHM, A5 and TensorTip MTX type hemoglobin monitors in plain environment and simulated environment at different altitudes, and the DSRs were compared.Logistic regression analysis was conducted to identify the risk factors affecting the success rate of instrument detection, and the cut-off value was determined by ROC curve and the Youden index. Results:In the simulated high-altitude environment of 3500, 4000 and 4500 m, the DSR of TensorTip MTX was significantly higher than that of Radical-7, NW-9002SHM and A5 ( P<0.001), and there was no significant difference in the DSR among Radical-7, NW-9002SHM and A5 ( P>0.05). Low SpO 2 was the main factor affecting the DSRs of the Radical-7, NW-9002SHM and A5 type hemoglobin monitor in high-altitude environment ( P<0.001), and the cut-off value of SpO 2 in determining the success of detection was 88.5%, 87.5% and 89.5%, respectively.The DSR of TensorTip MTX was not affected by low SpO 2. Conclusions:The DSR of TensorTip MTX hemoglobin monitor is minimally affected by the high-altitude environment and can be preferred in the absence of oxygen supply; when Radical-7, NW-9002SHM or A5 hemoglobin monitor applied in high-altitude environments, oxygen saturation needs to be increased to ensure a high DSR.

Comparison between pyrophosphate method and infrared spectrophotometry for determination of silicon dioxide content in dust / 中华劳动卫生职业病杂志

Objective@#To discuss the difference between pyrophosphoric acid method and infrared spectrophotometry for the determination of silica content in dust.@*Methods@#The content of silica in the laboratory comparison samples organized by CDC Occupational Health Institute in China in 2018, and purchased quality control samples were determined by pyrophosphate method. Meanwhile, the samples were qualitatively and quantitatively analyzed by infrared spectrophotometry, and the results obtained by the two methods were compared.@*Results@#Four samples (062C1、062C2、GDOHZKTG012-1、GDOHZKTG012-2) were detected by pyrophosphate method and infrared spectrophotometry. The results of pyrophosphate method were 55.49%, 5.24%, 4.90% and 54.72%, respectively. The results of infrared spectrophotometry were 0.91%, 1.87%, 1.29% and 1.16% respectively.@*Conclusion@#The content of silica in dust determined by pyrophosphate method is higher than that by infrared spectrophotometry.

Application of LIIR Automatic Analysis System of Infrared Spectroscopy in the determination of urinary stone composition / 中华泌尿外科杂志

Objective To determine the value of applying LIIR Automatic Analysis System of Infrared Spectroscopy in analyzing urinary stone composition. Methods 1450 samples of urinary stones were collected from 1032 male and 418 female patients. The age of patients ranged from 6 months to 88 years. The mean ages were 41.7±15.3 and 42.0±15.6 years for male and female patients, respectively. Of 1450 stones, 875 cases were located in kidney (60.34%), 504 cases in ureter (34.76%) and 71 cases in bladder (4.90%). All stones were analyzed by LIIR Automatic Analysis System of Infrared Spectroscopy (Tianjin). Analysis results were reevaluated by the artificial analysis of spectrogram, if necessary, with polarization microscope, chemical analysis, and X-ray diffraction.Results Calcium oxalate monohydrate stones were found in 714 cases (49. 24%), carbonate apatite stones in 444 cases (30.62%), anhydrous uric acid stones in 93 cases (6.41%), calcium oxalate dihydrate stones in 92 cases (6. 34 % ), ammonium magnesium phosphate hexahydrate stones in 28 cases (1.93%), cystine stones in 23 cases (1.59%), ammonium urate stones in 20 cases (1.38%), uric acid dihydrate stones in 16 cases (1.10%), brushite stones in 12 cases (0.83%), sodium urate monohydrate stones in 2 cases (0. 14%), calcium carbonate stones in 1 cases (0. 07%), and other stone types in 5 cases (0. 34%). Most urinary stones were composed of 2 or more compositions, and pure stones were only observed in 397 cases (27.38%). Most of the mixed stones contained calcium and non-calcium mixed stone was rarely observed. In addition, 15 stones were found in infants who had consumed melamine-contaminated milk powder. These stones were composed of uric acid dihydrate and ammonium urate. The results of reevaluation by artificial analysis showed the following: among pure and mixed stones, false detection occurred in 6 cases (0.41%), of which the composition was ammonium urate or carbonate apatite determined by automatic system but the true composition was anhydrous uric acid. False negative detection occurred in 9 cases (0.62%), of which the composition was ammonium magnesium phosphate hexahydrate or carbonate apatite in 7 cases, but in other 2 cases the composition could not be determined by artificial analysis. The false negative detection of components with relatively low content occurred in 6 cases and 10 cases in stones with 2 components and 3 components, respectively. The undetected composition in these cases was ammonium magnesium phosphate hexahydrate or carbonate apatite. Conclusion Automatic Analysis System of Infrared Spectroscopy has many advantages in accuracy, automation and is quick in analyzing the composition of urinary stones, and is worthy of promotion in clinical use.

Infrared imaging contribution for intestinal ischemia detection in wound healing / Contribuição da imagem infravermelha para detecção da isquemia intestinal na cicatrização das feridas

PURPOSE: To study thermal variations obtained through infrared image in rats, and to evaluate the relationship between intestinal ischemic time and histopathological findings. METHODS: Thirty Wistar rats were operated after distribution in 5 groups with different times of ischemia. Thermograms were obtained by using a infrared camera. The surgical technique has been standardized for all groups: abdominal cavity opening by a 5cm length incision in the midline, abdominal wall plans section and cavity exposure, and exteriorization of the intestine. In group I (control), it was proceeded only laparotomy without superior mesenteric artery ligature. After first thermogram done, incision was closed with continuing suture. In each rat in groups II, III, IV and V, the superior mesenteric artery was located at its origin on abdominal aorta, dissected and occluded with a vascular microclamp, subjecting the intestine to ischemia in variable times. RESULTS: Rats submitted to a 30 minutes ischemia presented reactive hyperemia, thermal differential of 1.8°C and normal pathological examination. The 1 hour ischemia produced reactive hyperemia with ischemic areas, thermal differential of 1.0°C and injuries at villosities' tips. However, the 90 minutes ischemia had not shown reactive hyperemia with large ischemic areas, thermal differential of -1.0°C and injury in the upper third of the villosities. The 2 hours ischemia demonstrated a severe ischemia, thermal differential of -2.0°C and injury throughout the all villosities' extension. CONCLUSION: It has been possible studying thermal variations through infrared image in rats, showing correlation between thermal response in thermograms, ischemic time and histopathological findings.

OBJETIVO: Estudar as variações térmicas obtidas por meio da imagem infravermelha em ratos, e avaliar sua correlação com o tempo de isquemia intestinal e os achados histopatológicos. MÉTODOS: Trinta ratos Wistar foram operados após distribuição em cinco grupos com diferentes tempos de isquemia. Os termogramas foram obtidos utilizando-se uma câmera infravermelha. A técnica operatória foi padronizada para todos os grupos, abertura da cavidade abdominal por uma incisão na linha média de 5 cm de comprimento com secção de todos os planos da parede abdominal e exposição da cavidade e as alças intestinais exteriorizadas. No grupo I (controle) foi feito apenas laparotomia sem ligadura da artéria mesentérica superior. Após realizado o primeiro termograma, foi fechada a incisão com sutura contínua. Em cada rato dos grupos II, III, IV e V a artéria mesentérica superior foi localizada em sua origem na aorta abdominal, dissecada com e ocluída por um microclampe vascular submetendo o intestino à isquemia em tempos variáveis. RESULTADOS: Os ratos submetidos à isquemia de 30 minutos apresentaram hiperemia reativa, diferencial térmico de 1,8°C e exame anatomopatológico normal. A isquemia de 1 hora produziu hiperemia reativa com áreas de isquemia, diferencial térmico de 1,0°C e lesões na ponta das vilosidades. Já a de 90 minutos não demonstrou hiperemia reativa com grandes áreas de isquemia, diferencial térmico de -1,0°C e lesão no terço superior das vilosidades. A isquemia de 2 horas mostrou isquemia grave, diferencial térmico de -2,0°C e lesão em toda a extensão das vilosidades. CONCLUSÃO: Foi possível estudar as variações térmicas por meio da imagem infravermelha em ratos, que mostrou haver correlação entre a resposta térmica dos termogramas, o tempo de isquemia e achados histopatológicos.

Incompatibilidad química y estabilidad térmica del baclofeno por análisis térmico

Se realizó un estudio de las posibles interacciones químicas entre el baclofeno, principio activo, y los distintos excipientes preseleccionados en la preformulación del baclofeno tableta, y al mismo tiempo un estudio de estabilidad térmica con el empleo de la calorimetría diferencial de barrido como técnica fundamental, la cual fue complementada con la cromatografía de capa fina y la espectroscopia infrarroja. Se obtuvo como resultado la no interacción química entre el principio activo y los excipientes; además se estableció un orden de estabilidad térmica con el propósito de realizar posibles sustituciones de algunos excipientes en la preformulación, con vistas a garantizar una mayor estabilidad del producto final.

A study of the possible chemical interactions between baclofen, active principle, and the different excipients preselected in the preformulation of baclofen tablet was conducted. A study of thermic stability by using the differential scanning calorimetry, which was complemented with thin layer chromatography and infrared spectroscopy, was carried out at the same time. As a result, the non-chemical interaction between the active principle and the excipients was obtained, and an order of thermic stability was established aimed at making possible substitutions of some excipients in the preformulation in order to guarantees a greater stability of the final product.