1.lnhibition of Radix lsatidis and its constituents indigo and indirubin on major organic anion transporters Oat1, Oat2 and Oat3 in mouse kidneys
Jinfeng QL ; Chen SUN ; Yonghui WANG ; Wenhao YU ; Jian HAN ; Mei LLN ; Na ZHANG
Chinese Journal of Pharmacology and Toxicology 2014;(6):878-886
OBJECTlVE To investigate the inhibition of Radix lsatidis and its major constituents indigo and indirubin on three principal subtypes of organic anion transporters ( OATs) , Oat1, Oat2 and Oat3 in vivo in mice. METHODS Granules of Radix lsatidis ( GRl) 0.615 and 2.46 g·kg-1 , decoction of Radix lsatidis ( DRl) 1.6 and 6.4 g·kg-1 , indigo 0.008 and 0.64 mg·kg-1 and indirubin 0.0192 and 1.536 mg·kg-1 were ig given to the NlH mice (60 mice per group), twice a day, for 5 d while four control groups were set up, including vehicle of water, 0.5%sodium carboxymethyl cellulose ( CMC) , positive control probe-necid (0.05 g·kg-1) and additives of sucrose plus dextrin (1.5 g·kg-1 each) groups. After the last dosing of the test samples, para-aminohippuric acid ( PAH) clearance test was conducted. All the mice were iv given PAH 0.03 g·kg-1 and 1, 2.5, 5, 7.5, 10 and 20 min later before 10 mice per group were euthanized to collect whole blood and the kidneys were quickly removed. Each right kidney was homoge-nized to analyze the PAH accumulations and each left kidney to extract total mRNA for analysis of Oat1, Oat2 and Oat3 gene expressions using quantitative real-time PCR. The concentrations of PAH in sera and in kidney homogenates were determined by the method of Kiguchi. Major pharmacokinetic parame-ters of PAH in sera were calculated by pharmacokinetic software ( DAS2.0) . PAH uptake test for kidney slices was performed on another group of NlH mice according to the method of Nakakariya. RESULTS There was no significant difference between water control group and 0.5%CMC group in all the examined items. Compared with the vehicle control groups ( water and 0. 5%CMC group ) , elimination half time ( t1/2β) of PAH in GRl 2.46 g·kg-1 ,indigo 0.64 mg·kg-1 and indirubin 1.536 mg·kg-1 groups was signifi-cantly prolonged (P<0.05), the total clearance (Cl) and volume of distribution (Vd) were obviously reduced ( P<0.01) and the area under the curve ( AUC0-20 min ) of PAH in all the tested groups was signifi-cantly increased ( P<0.01) . AUC0-20 min obtained from renal PAH accumulations within the checked time was significantly higher ( P<0.05, P<0.01) than in the vehicle control group. But there was in no signifi-cant difference between all the study groups in kidney-to-plasma AUC ratios. PAH uptake results by kidney slices were significantly lower ( P<0. 05, P<0. 01 ) than in vehicle control group in every two dosages of all the four samples tested. Compared with vehicle control group, the mRNA expressions of Oat1, Oat2 and Oat3 were obviously ( P<0.05, P<0.01) and abnormally regulated in the groups of GRl 2.46 g·kg-1, DRl 6.4 g·kg-1, indigo 0.64 mg·kg-1 and indirubin 1.536 mg·kg-1. CONCLUSlON The renal Oat1, Oat2 and Oat3 of mice are significantly inhibited by GRl, DRl, indigo and indirubin. The inhibitory function of Radix lsatidis probably stems from indigo and indirubin contained in it.
2.Effects of 10 Kinds of Nephrotoxic TCM on Kidney Organic Anion Transporter in Mice
Chen SUN ; Jinfeng QI ; Wenhao YU ; Yonghui WANG ; Mei LIN ; Na ZHANG
China Pharmacy 2015;(19):2673-2676
OBJECTIVE:To study the effects of 10 kinds of nephrotoxic TCM on three main subtypes(Oat1,Oat2 and Oat3) of kidney organic anion transporter(Oats)in mice. METHODS:A total of 1 840 SPF NIH mice were randomly divided into nor-mal control group(isovolumic pure water),probenecid group(30 kg/mg),sodium carboxymethyl cellulose(CMC)group,Pulsa-tillae radix,Corydalis rhizoma,Aconiti kusnezoffii radix,Aconiti radix,Angelicae pubescentis radix,Gleditsiae spina,Polygo-num cuspidatum,Kansui radix,Platycladi cacumen,Aucklandiae radix high and low dose groups. Mice were treated twice a day for 5 d,ig. After 1 h of the last dosing,they were iv given PAH in tail(30 mg/kg). The PAH pharmacokinetic parameters of the kidney homogenate were determined and the PAH intake in kidney tissue at the time point of 1,5,10,15 and 20 min was detect-ed. The PAH in blood was analyzed by DAS 2.0 software. The grouping and dosing were the same as before,after 1 h of the last dosing,kidney slices were made and put into PAH-buffer. The PAH intake of kidney slices was determined. RESULTS:Compared with normal control group,the t1/2β in C. rhizoma high dose group,A. kusnezoffii high and low dose groups,A. pubescentis high dose group,P. cuspidatum high and low dose groups and P. cacumen group were increased;Vd were all decreased in 10 kinds of TCM high and low dose groups;except for A. pubescentis low dose group,G. spian low dose group and K. radix low dose group, the CL was decreased and AUC0-20 min was increased in all other groups,with significant difference (P<0.01 or P<0.05). Com-pared with normal control group,the content of PAH in kidney tissue in P. radix high dose group,C. rhizoma high dose group,A. kusnezoffii high dose group,A. radix high and low dose groups,A. pubescentis high and low dose groups,G. spina high and low dose groups,P. cuspidatum high and low dose groups,K. radix high and low dose groups,P. cacumen high and low dose groups and A. radix high and low dose groups were increased,with significant difference (P<0.01 or P<0.05). Compared with normal control group,the intake of PAH in kidney slices in C. rhizoma high dose group,A. kusnezoffii high and low dose groups,G. spi-na high and low dose groups,K. radix high dose group,P. ca-cumen high and low dose groups and A. radix high dose group were decreased,with significant difference (P<0.01 or P<0.05). CONCLUSIONS:The 10 kinds of nephrotoxic TCM probably induced kidney injury through inhibiting the Oat1,Oat2 and Oat3 of Oats.
3.Influence of low-selenium diet on expression of selenium-binding protein 1 and selenoprotein P in mouse liver, kidney and brain tissues
Mei-na, SUN ; Han-dong, ZHAO ; Yi-tong, ZHANG ; Hui, LI
Chinese Journal of Endemiology 2013;32(6):636-638
Objective To explore the influence of low-selenium diet on expression of selenium-binding protein 1 (SBP1) and selenoprotein P (Sel P) in liver,kidney and brain tissues.Methods C57BL/6 mice were randomly divided into four groups according to body weight:control group,low-selenium treatment for 4-,12-and 24-week groups,10 mice in each group,half male and half female.The control group was fed with normal diet (selenium content was 0.300 mg/kg),distilled water,and sacrificed at the 12th week; low-selenium treatment groups were fed with low-selenium diet(selenium content was 0.015 mg/kg),then sacrificed at the 4th,12th and 24th weeks,respectively.Expressions of SBP1 and Sel P in mouse liver,kidney and brain tissues were determined by Western blotting.Results Expressions of SBP1 and Sel P in low-selenium feed mouse liver tissue at the 4th,12th and 24th weeks were,respectively,as follows 0.11 ± 0.01,0.36 ± 0.01,0.59 ± 0.02 and 0.41 ± 0.01,0.39 ± 0.02,0.25 ± 0.02;in kidney,respectively,as follows 0.60 ± 0.03,0.20 ± 0.02,0.03 ± 0.01 and 0.88 ± 0.01,0.73 ± 0.03,0.85 ± 0.02; in brain,respectively,as follows 0.54 ± 0.03,0.11 ± 0.01,0.01 ± 0.01 and 0.50 ± 0.02,0.49 ± 0.03,0.38 ± 0.02.Expression of Sel P in low-selenium feed mouse liver,kidney and brain tissues was significantly decreased as compared to that of control group(1.00 ± 0.00,1.00 ± 0.00,all P < 0.05),but SBP1 content was reduced at first and then rebounded in kidney,and was in decreasing trend in liver and brain tissues.Conclusion Low-selenium diet has a certain effect on expression of SBP1 and Sel P in mouse liver,kidney and brain tissues.
4.Effects of Radix Isatidis and contained indigo and indirubin on organic cation transporters OCT1 and OCT2 in mouse kidney
Na ZHANG ; Jinfeng QI ; Chen SUN ; Wenhao YU ; Yonghui WANG ; Mei LIN
Chinese Journal of Pharmacology and Toxicology 2016;(2):127-134
OBJECTIVE To investigate the effect of Radix Isatidis and its constituents indigo and in?dirubin on two principal subtypes of organic cation transporters(OCT)OCT1,OCT2 in vivo in mice. METHODS Decoction of Radix Isatidis (DRI) 1.6 and 6.4 g · kg-1,granules of Radix Isatidis (GRI) 0.615 and 2.460 g·kg-1,indigo 0.008 and 0.640 mg·kg-1 and indirubin 0.0192 and 1.536 mg·kg-1 were ig given to NIH mice(60 mice per group),twice a day for 5 d. Four control groups were set up,including the vehicle of water,0.5% sodium carboxymethyl cellulose(CMC),additives of sucrose plus dextrin (1.5 g · kg-1)and positive control quinidine(0.025 g · kg-1). Sixty minutes after the last dosing,all the mice were iv given metformin(Met)5 mg·kg-1,and at 1.0,2.5,5.0,7.5,10.0 and 20.0 min after Met iv,10 mice in each group were sacrificed to collect whole blood and kidneys respectively. The right kidney was homogenized for Met accumulation test and the left one used to extract total RNA for analysis of OCT1 and OCT2 mRNA expressions by real-time PCR. The contents of Met in sera and kidneys were quantified by HPLC. Major pharmacokinetic parameters of Met in sera were analyzed by pharmacokinetic software(DAS 2.0). RESULTS There was no significant difference between water control group,0.5%CMC group and sucrose plus dextrin group in any examined item. Compared with vehicle control group (water and 0.5%CMC group),all the related pharmacokinetic parameters in DRI 6.4 g · kg- 1,GRI 2.46 g · kg-1,indigo 0.640 mg · kg-1 and indirubin 1.536 mg · kg-1 groups were changed significantly (P<0.05,P<0.01). The elimination half time (t1/2β) was prolonged 13%-97%,volume of distribution reduced by 13%-72%,clearance(Cl)reduced by 9%-65%,and the area under the concentration-time curve (AUC0-20 min) increased by 13%-135%. AUC0-20 min obtained from renal Met accumulations was significantly increased(P<0.01)while Met uptake by kidney slices was reduced(P<0.05,P<0.01). The expressions of OCT1 and OCT2 mRNA were obviously down-regulated(P<0.05,P<0.01). CONCLUSION The mouse renal OCT1 and OCT2 are significantly inhibited by DRI,GRI,indigo and indirubin. The inhibitory effect of Radix Isatidis on OCT1 and OCT2 probably arises from indigo and indirubin contained.
5.Investigation on iodine nutritional status and intelligent development in target populations in Akesu Prefecture of Xianjing Autonomous Region
Xing, LI ; Yong-mei, LI ; Ming, QIAN ; Yi-na, SUN ; ANIWAR ; Dong-yang, LI ; Yu-qin, YAN ; Zu-pei, CHEN
Chinese Journal of Endemiology 2009;28(3):306-308
Objective To investigate the iodine nutritional status of school children, lactating women and infants in iodine deficient areas of Baicheng and Wushi Counties in Xinjiang Autonomous Region. Methods According to the geographic location of east, south, west and north of county, 10 primary schools of 8 townships were selected. In each school, 10 children among each gender and age group from 8 to 10 years old were selected. A total of 300 school children were chosen. One hundred and four infants aged 0-2 years old and their mother were selected in 8 townships. Iodine content in edible salt at household level, the urinary iodine in school children and lactating women, total goiter rate(TGR) and the status of the intelligence quotient (1Q) of school children, the status of psychological development of infants were observed. Direct titration assay for testing the salt iodine, colorimetric ceric-arsenic assay and vitriolic ammonium assimilation were used for testing urinary iodine. The size of thyroid gland was measured by palpation. The Combined Raven Test for Chinese Rural was used to test the IQ. The psychological development of infants was tested by Danver Development Screening Test (DDST). Results The coverage rate of iodized salt at household level was 73.1% (123/182), however, the proportion of households using adequately iodized salt was 64.1% (118/182). The medium of urinary iodine in school children was 103.7 μ/L, with 47.8%(75/157) less than 100 μg/L and 28.0% (44/157) less than 50 μg/L; it was 123.0 μg/L in Baieheng County, with 44.4%(28/63) less than 100 μg/L and 33.3%(21/63) less than 50 μg/L; it was 100.3 μg/L in Wushi County, 50.0%(47/94) less than 100 μg/L and 24.5%(23/94) less than 50 μg/L. The medium of urinary iodine in locating women was 143.3 μg/L, it was 119.7 μg/L and 184.6 μg/L in Baicheng and Wushi Counties, respectively. The total rate of goiter in school children was 14.3%(43/300), it was 10.8%(13/120) and 16.6%(30/180) in Baicheng and Wushi Counties, respectively. The average IQ in school children was 80.6±11.6, it was 83.0±11.6 and 79.0±11.7 in Baicheng and Wushi Counties, respectively. The proportion of mental retardation in school children (IQ≤69) was 13.0% (39/300), it was 6.7% (8/120) and 17.2%(31/180) in Baicheng and Wushi Counties, respectively. In addition, the proportion of psychological development in infants being normal, suspicious and abnormal was 78.8%(82/104), 12.5% (13/104) and 8.7%(9/104), respectively. Conclusion This study confirms the fact that there is also existence of mental retardation in children and infants, caused by iodine deficiency.
6.Study of the thermal pain threshold latency of acupoints based on Fei Teng Ba Fa
Hong-Bin WANG ; Shu ZHAO ; Jian-Mei CUI ; Yan CAO ; Na SUN ; Jian-Shuai QI ; Yue-Yue YU ; Jue HONG
Journal of Acupuncture and Tuina Science 2018;16(3):140-144
Objective:By applying moxibustion to the eight confluent points in different periods of time,to observe the changes in thermal pain threshold latency of acupoints based on Fei Teng Ba Fa.Methods:A total of 468 healthy college student volunteers received moxibustion at the eight confluent points in three different periods of time,i.e.Chen (7:00-9:00),Wu (11:00-13:00) and Xu (19:00-21:00).The thermal pain threshold latency was adopted to measure the changes in pain threshold of the eight confluent points under different conditions (different periods of time,different genders,different acupoints and different states of the acupoints) based on Fei Teng Ba Fa.Results:Finally,thirty subjects dropped out and 438 subjects were included.The comparison of thermal pain threshold latencies of the eight confluent points in the same opening or closing state based on Fei Teng Ba Fa:latencies of the closing points and adjunct points were significantly different in different periods of time (P<0.05);the latencies of the males were significantly longer than those of the females (P<0.05);there was no significant difference in the latency between the left and right sides (P>0.05);in the female group,there was a significant difference in the latency between the lower-limb points and the upper-limb points (P<0.05).The comparison of thermal point threshold latencies of the eight confluent points in different opening or closing state:in the period of Wu (11:00-13:00),the latencies of the opening points were significantly longer than those of the closing points and adjunct points (P<0.05);for men,their opening and closing points had significantly longer thermal pain threshold latencies than their adjunct points (P<0.05);despite the gender,the latencies of the upper limb opening and closing points were significantly longer than the latency of the adjunct points (P<0.05);in the female group,the latencies of the lower-limb opening points were significantly shorter than those of the lower-limb closing and adjunct points (P<0.05).Conclusion:Based on Fei Teng Ba Fa,the pain thresholds of the eight confluent points vary in different periods of time,gender,acupoint location and opening/closing state,which can be taken as the evidence of making time-based acupuncture-moxibustion prescriptions.
7.Preliminary experimental study on iodine concentration in iodized Nang(bread)
Yong-mei, LI ; Xing, LI ; Ni-woer, AN ; Ming, QIAN ; Lai-xiang, LIN ; Yi-na, SUN ; Zu-pei, CHEN
Chinese Journal of Endemiology 2010;29(2):155-157
Objective To explore the feasibility of iodized Nang(bread) prepared with iodized salt and non-iodized rock salt as vehicle of iodine. Methods Two kinds of Nang, each of 10 respectively, were grilled with 30 g iodized salt water and non-iodized rock salt water mixed with 2 kg flour by the local cooker, then put inside of Nang oven using traditional methods of grilled Nang in Xinjiang. The samples were collected from different parts of Nang, including the layers facing oven wall and the fire, as well as inside of Nang. The method for determination of iodine in foodstuff by dry ashing As ~Ⅲ-Ce~(4+) catalytic spectrephotometry was used to determine iodine concentration in Nang. Results Iodine content in iodized and non-iodized Nang was (0.654 ± 0.076)mg/kg and (0.075 ± 0.022)mg/kg, respectively. In addition, Iodine content in two kinds of Nang was significantly different and iodine content of Nang with iodized salt was much higher than that with non-iodized rock salt(t = 13.520, P <0.01 ). Iodine content in two kinds of Nang from the layers facing oven wall and the fire, as well as inside of Nang were (0.700 ± 0.100), (0.064 ± 0.029)mg/kg; (0.647 ± 0.076), (0.070 ± 0.019)mg/kg; (0.659 ± 0.073), (0.073 ±0.030)mg/kg, respectively. Iodine content in two kinds of Nang of the same parts was significantly different(t =3.826,4.201,4.103, all P < 0.01 ). There was no significant difference of iodine content in different parts of the same kind of Nang(F = 0.220,0.190, all P > 0.05). Conclusions Grilled Nang with iodized salt contains sufficient iodine, and the iodine content of the same kind of Nang in different parts has no significant difference. Our studydemonstrated that Nang is a vehicle available for iodine fortification since Nang is very popular food for local population in Xinjiang.
8.A comparative study on alkaline ashing method and chloric acid digestion method for determination of human milk iodine
Yi-na, SUN ; Jin-ru, DONG ; Tong-mei, FAN ; Yong-mei, LI ; Yan, YE ; Lai-xiang, LIN ; YU-qin, YAN ; Zu-pei, CHEN ; Shou-jun, LIU
Chinese Journal of Endemiology 2011;30(3):342-344
Objective Take alkaline ashing method as golden standard to explore the accuracy of chloric acid digestion method in determination of human milk iodine. Methods Sixty one breast milk samples collected in Hexi district of Tianjin was measured by the method for determination of iodine in foodstuff by As3+-Ce4+ catalytic spectrophotometry (referred to as the alkaline ashing method) published in 2008 and the method for determination of iodine in urine by As3+-Ce4+ catalytic spectrophotometry(referred to as acid digestion) published in 1999, respectively. were highly correlated(r = 0.960, t = 26.3, P < 0.01), and the regression equation was (Y) = - 28.1 + 0.808X, in which X was independent variable, that is the results of alkaline ashing method; (Y) was dependent variable, that is the estimated data of chloric acid digestion method. The average difference of the results measured by the two methods was 68.3 μg/L, and the results from chloric acid digestion was 38.9% which lower than that of alkaline samples were diluted by 3,4 and 5-fold and then digested by chloric acid, the liquid clarification rates were 80.3% ashing and chloric acid digestion method were, respectively, 165.4, 110.0 μg/L. Conclusions Compared with alkaline ashing method, the results determined by chloric acid digestion method are significantly lower. It is suggested that there are systemic errors in chloric acid digestion method, which means that alkaline ashing method can not be replaced by the chloric acid digestion method.
9.Long-term effects of early hyperbaric oxygen therapy on neonatal rats with hypoxic-ischemic brain damage.
Mei-Na LIU ; Si-Qi ZHUANG ; Hong-Yu ZHANG ; Zhao-Yuan QIN ; Xiao-Yu LI
Chinese Journal of Contemporary Pediatrics 2006;8(3):216-220
OBJECTIVEThe application and therapeutic effect of hyperbaric oxygen (HBO) in hypoxic-ischemic brain damage (HIBD) remains controversial. Previous studies have focused on the early pathological and biochemical outcomes and there is a lack of long-term functional evaluation. This study was designed to evaluate the long-term pathological and behavioral changes of early HBO therapy on neonatal rats with HIBD.
METHODSPostnatal 7 days (PD7) rat pups were randomly assigned into Control (n=18), HIBD (n=17) and HBO treatment groups (n=17). HIBD was induced by ligating the left common carotid, followed by 2 hrs hypoxia exposure in the HIBD and HBO treatment groups. The Control group was sham-operated and was not subjected to hypoxia exposure. The HBO therapy with 2 atmosphere absolutes began 0.5-1 hr after HIBD in the HIBD treatment group, once daily for 2 days. The spatial learning and memory ability were evaluated by the Morris water maze test at PD37 to PD41. The morphological and histological changes of the brain, including brain weight, survival neurons, AchE positive unit and NOS positive neurons in hippocampal CA1 region, were detected at PD42.
RESULTSThe rats in the HIBD group displayed significant morphological and histological deficits, as well as severe spatial learning and memory disability. In the Morris water maze test, the mean escape latency were longer (56.35 +/- 22.37 s vs 23.07 +/- 16.28 s; P < 0.05) and the probe time and probe length were shorter in the HIBD group (29.29 +/- 6.06 s vs 51.21 +/- 4.59 s and 548 +/- 92 cm vs 989 +/- 101 cm; both P < 0.05) compared with the Control group. The left brain weight in the HIBD group was lighter than that in the Control group (0.601 +/- 0.59 g vs 0.984 +/- 0.18 g; P < 0.05). The survival neurons in the hippocampal CA1 region were less (100 +/- 27/mm vs 183 +/- 8/mm; P < 0.05), as well as the AchE-positive unit and NOS-positive neurons (18.50 +/- 2.24% vs 27.50 +/- 2.18% and 19.25 +/- 4.33 vs 33.75 +/- 5.57 respectively; P < 0.05) after HIBD. Early HBO treatment improved the abilities of spatial learning and alleviated the morphological and histological damage. The mean escape latency (39.17 +/- 21.20 s) was shortened, the probe time (36.84 +/- 4.36 s) and the probe length (686 +/- 76 cm) were longer, and the brain weight (0.768 +/- 0.85 g), the survival neurons (133 +/- 25/mm) and the AchE-positive unit (21.94 +/- 2.73%) increased significantly compared with those of the HIBD group (P < 0.05).
CONCLUSIONSEarly HBO treatment resulted in a protective effect against HIBD-induced long-term brain morphological and histological deficits and spatial learning and memory disability.
Acetylcholinesterase ; analysis ; Animals ; Brain ; pathology ; Escape Reaction ; Female ; Hippocampus ; enzymology ; pathology ; Hyperbaric Oxygenation ; Hypoxia-Ischemia, Brain ; enzymology ; pathology ; therapy ; Male ; Maze Learning ; Nitric Oxide Synthase ; analysis ; Rats ; Rats, Sprague-Dawley
10.Circulatory breathing abnormality: Clinical observation on exercise induced oscillatory breathing pattern.
Xue-mei ZHANG ; Xing-guo SUN ; P AGOSTONI ; Fang LIU ; Na ZHOU ; Xiao-yue TAN ; Gui-qing SONG ; Lei GU ; Ning-hua LIU
Chinese Journal of Applied Physiology 2015;31(4):365-368
OBJECTIVEExercise induced oscillatory ventilation (EIOB) during cardiopulmonary exercise testing (CPET) is associated with severity and prognosis of disease, but clinical approach for the character of EIOB due to circulatory dysfunction are seldom reported.
METHODSThis retrospective analysis of symptom-limited maximum CPET data with an increment of 10-20 W/min in 38 patients with CHF. We calculated the duration, frequency, amplitude and other parameters of EIOB.
RESULTSThere were 31 presenting with EIOB (82%) in all patients with CHF. In EIOB group, VE amplitude were (12.4 ± 4.4)L/min (accounting for 81% ± 30% of mean) and duration were (77.0 ± 20.0)s. The number of patients whose EIOB presenting at rest, exercise, recovery stage and the whole eriod were 24, 31, 4 and 4, respectively. Except VE, there were VO2, VCO2, RER and PETO2 presenting EIOB in all 31 patients; VE/VCO2, VO2/VE and breath frequency in 29 patients; PETCO2 in 26 patients; VT and VO2/HR in 25 patients; and HR in 2 patients.
CONCLUSIONEIOB may occur in any period of CPET, mostly in severe patient with CHF, and presenting in many variables. Due to it is resulted from the circulatory dysfunction, we should call it circulatory (cardiac) oscillatory breathing abnormality.
Exercise Test ; Heart Failure ; physiopathology ; Humans ; Oxygen Consumption ; Respiratory Physiological Phenomena ; Retrospective Studies