Evaluation of the visualized left atrium by 201Tl myocardial scintigraphy

201Tl myocardial scintigraphy was evaluated in patients with 18 mitral stenosis cases. Left atrium was to be seen in ANT (16.7%), LAO (16.7%), MLAO (16.7%) and L-LAT (11.1%), respectively. Furthermore, 201Tl uptake ratio of left atrium, right ventricle, pulmonary area tended significantly to increase in visible group compared with invisible group. PCW pressure was correlated with left atrial Tl uptake (r = 0.51, p less than 0.005), and it indicated some correlation between left atrial pressure and 201Tl uptake.     

Measurement of the liver and spleen volume by single photon emission computed tomography

Organ volume was experimentally and clinically determined using single photon emission computed tomography (SPECT). In organ phantom filling with 99mTcO4-, the error was less than 3.3% in the volume over 400 ml but 11% at 200 ml. In 28 cases of patient, liver and spleen volume were measured by SPECT and X-CT. Good correlation was founded between SPECT volume and X-CT volume (r = 0.99, n = 49), although SPECT volume were 16% higher than X-CT volume (y = 1.16 x + 11.6, x: X-CT volume, y: SPECT volume).     

Evaluation of prognosis in patients with old myocardial infarction--using 201Tl myocardial scintigraphy and 99mTc cardiac scintigraphy

To evaluate the prognosis in 57 patients with old myocardial infarctions, 201Tl myocardial scintigraphy and 99mTc-HSA gated blood pool scan had been done as a 5-year follow up study. We subdivided into two groups; group I (over 60 years) and group II (under 60 years). Cardiac index (CI) and right ventricular ejection fraction (RVEF) did not change significantly, however left ventricular ejection fraction (LVEF) changed significantly (p less than 0.05). Correlationship between CAG score and delta LVEF by handgrip exercise test was y = -1.34 x +3.61 (n = 44, r = -0.400, p less than 0.01). Otherwise, Tl defect ratio between first and final examination did not show the significant change in two groups. In conclusion, nuclear examination (cardiac function and myocardial blood flow) is significant to evaluate the prognosis in patients with myocardial infarction.     

New whole blood methods and instruments: glucose measurement and test menus for critical care.

A glucose oxidase-H 2O 2 substrate-selective electrode (SSE) along with eight other electrodes allows the Stat Profile 5 (SP5) to measure glucose, electrolytes, blood gases, pH, and hematocrit simultaneously in whole blood. For heparinized blood gas syringe samples (n=178), orthogonal (Deming) regression showed y=0.43 + 1.00x (mmol/L), where y is whole blood glucose, and x is plasma glucose measured with the Ektachem 400 glucose oxidase slide method. For heparinized plasma (n=197), y=0.25 + 1.02x. Least squares linear regression showed y=0.25 + 1.00x (s yxx=0.49) for whole blood versus plasma, y = 0.30 + 1.01x (s yxx=0.49) for plasma versus plasma, and r=0.994 for both cases. Whole blood and plasma glucose in the same samples measured by SSE differed by less than 1%. The SP5 combines the largest number of whole blood tests currently available in a rapid response instrument well-suited for care of the critically ill patient.     

Renal function study with 111In-DTPA--in comparison with 99mTc-DTPA

Technetium-99m-diethylene-triamine-penta-acetic acid (DTPA) and 111In-DTPA were injected simultaneously into 21 patients with various levels of renal function. Scintiphoto, camera data renograms and clearance values (plasma sampling) were obtained for each patient. The mixed isotope scintiphoto images were of intermediate quality and the images with 111In-DTPA were apparently inferior to those with 99mTc-DTPA. These equations were obtained: (1) y = 0.30 + 0.91 x (coefficient of correlation r = 0.98) where x is the value at T peak (time of maximum count on renogram) obtained with 99mTc-DTPA and where y is the value at T peak with 111In-DTPA. (2) y = -0.09 + 1.006 x (r = 0.99) where x is the value at T3/4 (time interval between the time of maximum count to the time of 3/4 of maximum count on renogram) and where y is the value at T3/4 obtained with 111In-DTPA. (3) y = -0.01 + 1.007 x (r = 0.98) where the x and y values were for the excretion ratios (counts at 20 min/maximum counts on renogram). (4) y = 0.81 + 0.98 x (r = 0.99) where x and y are the clearance values.     

Rapid determination of chloramphenicol residues in aquaculture tissues by immunochromatographic assay.

An immunochromatographic assay was developed to detect chloramphenicol (CAP) residues in aquaculture tissues. The limit of detection (LOD) was 10 ng g(-1) for detecting CAP spiked in the aquaculture tissues. The results were confirmed by liquid chromatography tandem mass spectrometry (LC/MS/MS) and indicated that there was a good agreement between the two methods. The linear regression equation was y = 1.19x + 0.539 with R(2) = 0.978. The assay time for test was less than 5 min and the method is suitable for rapid testing on-site.     

Monoclonal-based enzyme-linked immunosorbent assay and immunochromatographic assay for enrofloxacin in biological matrices

Enrofloxacin has been increasingly used in veterinary medicine to treat microbial infections. A simple and reliable analytical method for this drug is required. The current determination by high performance liquid chromatography (HPLC) is sensitive but labor-intensive. This paper reports an enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody (MAb) and the development of a rapid test kit based on immunochromatography. The detection limits using the ELISA were 10 ppb for chicken liver and muscle, and 1 ppb for cattle milk, respectively. The mean recovery values were 77.3-96.0% for chicken liver, 72.4-92.0% for chicken muscle and 84.0-99.0% for cattle milk. The detection limits using the kit were ca. 100 ppb for chicken muscle and ca. 10 ppb for cattle milk, respectively. All ELISA results for assay of chicken liver, chicken muscle and cattle milk were confirmed using HPLC which is used as the routine assay. The HPLC (x) and ELISA (y) results showed close correlation for chicken liver (y = 8.7 + 0.85x, r2 = 0.99, n = 25), chicken muscle (y = -3.9 + 0.94x, r2 = 0.98, n = 25) and cattle milk (y = 18.4 + 0.92x, r2 = 0.99, n = 25).     

Evaluation of diastolic phase by left ventricular volume curve using S2-gated equilibrium method in radioisotope angiography

S2-gated (the second heart sound) method was designed by authors. In 6 normal subjects and 16 patients (old myocardial infarction 12 cases, hypertension 2 cases and aortic regurgitation 2 cases), radioisotope (RI) angiography using S2-gated equilibrium method was performed. In RI angiography, 99mTc-human serum albumin (HSA) 555MBq (15 mCi) as tracer, PDP11/34 as minicomputer and PCG/ECG synchronizer (Metro Inst.) were used. Then left ventricular (LV) volume curve by S2-gated and electrocardiogram (ECG) R wave-gated method were obtained. Using LV volume curve, left ventricular ejection fraction (EF), mean ejection rate (mER, s-1), mean filling rate (mFR, s-1) and rapid filling fraction (RFF) were calculated. mFR indicated mean filling rate during rapid filling phase. RFF was defined as the filling fraction during rapid filling phase among stroke volume. S2-gated method was reliable in evaluation of early diastolic phase, compared with ECG-gated method. There was the difference between RFF in normal group and myocardial infarction (MI) group (p less than 0.005). RFF in 2 groups were correlated with EF (r = 0.82, p less than 0.01). RFF was useful in evaluating MI cases who had normal EF values. The comparison with mER by ECG-gated and mFR by S2-gated was useful in evaluating MI cases who had normal mER values. mFR was remarkably lower than mER in MI group, but was equal to mER in normal group approximately. In conclusion, the evaluation using RFF and mFR by S2-gated method was useful in MI cases who had normal systolic phase indices.     

高效液相色谱法测定尿液中的异硫氰酸酯

 省去合成1,3 苯二硫杂环五烯 2 硫酮这一步骤，直接用异硫氰酸丙基酯与1,2 苯二硫酚反应作标准，建立了尿液中异硫氰酸酯的反相高效液相色谱(HPLC)测定方法。异硫氰酸丙基酯的标准曲线回归方程 y =0.418 2x + 2.821 ( r2 = 0.999 3 )与异硫氰酸甲基酯的回归方程 y = 0.412 2x + 2.442 3 ( r 2= 0.996 6 )基本拟合。检出限(以信噪比为2.5计)为0.08 μ mol/L 。日内重现性( n =21)以相对标准偏差(RSD)表     

Use of isotopically labelled octanoic acid to assess the effect of meal size on gastric emptying

It has been proposed that the (13)C-octanoic acid breath test (OBT) provides a safe, non-radioactive means of measuring gastric emptying. However, deuterated octanoic acid provides a better marker when compared with scintigraphy, as the kinetics are less complex than those of the (13)C label. The appearance of (2)H in saliva is modelled as a two-compartment body water system, using an asymmetric triangular gastric emptying function. This study compared the (2)H-octanoic acid saliva test (OST) with the OBT in measuring altered states of gastric emptying in the nutritional context of diet manipulation. Gastric emptying was measured using the OST and OBT in a three-way crossover study involving 12 healthy male and female subjects (mean BMI = 23.4 kg/m(2), aged 24-57 years). Following an overnight fast, subjects were given an egg meal, labelled with 10 microL/kg body weight (2)H-octanoic acid and 100 microL (13)C-octanoic acid. The meal was nutritionally manipulated to provide a 1 MJ, 2 MJ or 3 MJ meal. Breath and saliva samples were collected at regular intervals for 6 h, with further saliva samples being collected over four subsequent days. (2)H isotopic enrichment in saliva and (13)C isotopic enrichment in breath were analysed using isotope ratio mass spectrometry and the data fitted to the respective gastric emptying models. The half excretion time (T(1/2) (D)), time to maximum emptying rate (T(1) (D)) and time when emptying is complete (T(2) (D)) were calculated from the (2)H saliva test data, and the lag time (T(lag) (C)), half excretion time (T(1/2) (C)), latency phase (T(lat) (C)) and ascension time (T(asc) (C)) were calculated from the (13)C breath test data. Overall, the OBT correlated well with the OST, with a significant relationship between T(1/2) (C) and T(1/2) (D), a significant relationship between T(lat) (C) and T(1) (D) and finally a significant relationship between T(asc) (C) and T(2) (D). Gastric emptying measured using the OST was significantly faster with the 1 MJ meal (DeltaT(1/2) (D) = -0.77 h vs. 2 MJ, p = 0.004). Increases were also seen when the meal size was increased from 2 MJ to 3 MJ (DeltaT(1/2) (D) = +0.44 h vs. 2 MJ), but these were not significant. These trends were mirrored in the OBT data, with significant differences between 1 MJ and 2 MJ (DeltaT(1/2) (C) = -0.63 h vs. 2 MJ, p = 0.013) and non-significant increases with the larger 3 MJ meal (DeltaT(1/2) (C) = +0.10 h vs. 2 MJ). Total meal calorie content was shown to have an effect on gastric emptying using both the OBT and the OST. The deuterium method allows the direct calculation of the gastric emptying function and could be used as an alternative to gamma scintigraphy, allowing further validation of the (13)C-octanoic acid breath test.     

Plasma antioxidant capacity determination: comparative evaluation of chemiluminescent and spectrophotometric assays

All aerobic organisms have developed different mechanisms for neutralising the free radicals, mostly produced by the monoelectronic reduction of O(2), and preventing the severe damages these can provoke. The efficiency of these mechanisms can be assessed, in different matrices, by a simple and direct chemiluminescent assay (CL) based on luminol oxidation catalysed by horseradish peroxidase. Light emission is mediated by the production of free radicals and it is inhibited after a sample addition in a way that is directly proportional to the sample total content of molecules displaying antioxidant activity. The performances of this chemiluminescent assay were compared with those of two spectrophotometric methods already applied in clinical practice. First spectrophotometric method measures, like CL assay, the total antioxidant capacity, whereas the second one determines free thiol groups content. The chemiluminescent assay has a linearity interval between 0.60 and 9.46 mumol l(-1) of Trolox (y=34.91x+3.10; r=0.999; n=5) with an imprecision, expressed as CV, of 3.8% and an inaccuracy, expressed as percentage recovery, of 109%. The first spectrophotometric method, based on the same reference standard, the Trolox molecule, has a linearity interval between 0.2 and 2.5 mmol l(-1) of Trolox (y=-0.01x+4.54; r=0.95; n=5); the thiol groups assay has a linearity interval between 0.1 and 1 mmol l(-1) of l-cysteine (y=1.68x-47.09; r=0.998; n=5). Different clinical samples of plasma from healthy individuals, obese subjects and patients with liver diseases were tested. Interesting correlations were obtained among the three methods, but no significant correlations emerged between antioxidant capacity and clinical parameters. Significant differences were there only between men and women among obese subjects and between drinkers and non-drinkers among liver disease patients.     

Determination of ascorbic acid content of some fruit juices and wine by voltammetry performed at pt and carbon paste electrodes

A method was developed for assessing ascorbic acid concentration in fruit juices and wine by differential pulse voltammetry. The oxidation peak for ascorbic acid occurs at about 530 mV (versus SCE) on a Pt strip working electrode and at about 470 mV on a carbon paste working electrode. The influence of the operational parameters like the pulse amplitude and the pulse period on the analytical signal was investigated. The obtained calibration graph shows a linear dependence between the peak height and ascorbic acid concentration within the range 0.31-20 mM with a Pt working electrode, and within the range 0.07-20 mM with a carbon paste working electrode. The equation of the calibration graph was y = 21.839x + 35.726, r2 = 0.9940, when a Pt strip electrode was used (where y represents the value of the current intensity measured for the peak height, expressed as μA and x the analyte concentration, as mM). R.S.D. = 2.09%, n = 10, C(ascorbic acid) = 2.5 mM. The equation of the calibration graph was y = 3.4429x + 5.7334, r2 = 0.9971, when a carbon paste electrode was used (where y represents the value of intensity measured for the peak height, expressed as μA and x the analyte concentration, as mM). R.S.D. = 2.35%, n = 10, C(ascorbic acid) = 2.5 mM. The developed method was applied to ascorbic acid assessment in fruit juices and wine. The ascorbic acid content determined ranged between 6.83 mg/100 mL juice for soft drinks (Fanta Madness) and 54.74 mg/100 mL for citrus (lemon) juices obtained by squeezing fruit. Different ascorbic acid concentrations (from standard solutions) were added to the analysed samples, the degree of recovery being comprised between 94.74 and 104.97%. The results of ascorbic acid assessment by differential pulse voltammetry were compared with those obtained by cyclic voltammetry. The results obtained by the two methods were in good agreement.     

Kinetics of Dissociation of Iron(III) Complexes of Tiron in Aqueous Acid

The kinetics of dissociation of the mono, bis, and tris complexes of Tiron (1,2-dihydroxy-3,5-benzenedisulfonate) have been studied in acidic aqueous solutions in 1.0 M HClO(4)/NaClO(4), as a function of [H(+)] and temperature. In general, the kinetics can be explained by two reactions, (H(2)O)Fe(L)(n)(-1) + H(2)L right arrow over left arrow (H(2)O)Fe(L(n)H) + H(+) (k(n), k(-n)) and (HO)Fe(L)(n)(-1) + H(2)L right arrow over left arrow (H(2)O)Fe(L(n)H) (k(n)', k(-n)'), a rapid equilibrium, (H(2)O)Fe(L(n)H) right arrow over left arrow (H(2)O)Fe(L)(n) + H(+) (K(cn)), and the formation constant (H(2)O)Fe(L)(n)(-1) + H(2)L right arrow over left arrow (H(2)O)Fe(L)(n) + 2H(+). For n = 1, the reaction was observed at 670 nm, and at [H(+)] of 0.05-0.5 M at temperatures of 2.0, 14.0, 25.0, and 36.7 degrees C. For n = 2, the analogous conditions are 562 nm, at [H(+)] of 1.5 x 10(-3) to 1.4 x 10(-2) M at temperatures of 2.0, 9.0, and 14.0 degrees C. For n = 3, the conditions are 482 nm, at pH 4.5-5.7 in 0.02 M acetate buffer at temperatures of 1.8, 8.0, and 14.5 degrees C. The rate or equilibrium constants (25 degrees C) with DeltaH or DeltaH degrees (kcal mol(-1)) and DeltaS or DeltaS degrees (cal mol(-1) K(-1)) in brackets are as follows: for n = 1, k(1) = 2.3 M(-1) s(-1) (8.9, -27.1), k(-1) = 1.18 M(-1) s(-1) (4.04, -44.8), K(c1) = 0.96 M (-9.99, -33.6), K(f1) = 2.01 M (-5.14, -15.85); for n = 2, k(-2)/K(c2) = 1.9 x 10(7) (19.9, 41.5) and k(-2)'/K(c2) = 1.85 x 10(3) (1.4, -38.8) and a lower limit of K(c2) > 0.015 M; for n = 3, k(3) = 7.7 x 10(3) (15.8, 12.3), k(-3) = 1.7 x 10(7) (16.2, 28.9), K(c3) = 7.4 x 10(-5) M (4.1, -5.1), and K(f3) = 3.35 x 10(-8) (3.7, -21.7). From the variations in rate constants and activation parameters, it is suggested that the Fe(L)(2) and Fe(L)(3) complexes undergo substitution by dissociative activation, promoted by the catecholate ligands.     

Three-dimensional configurations of organic/inorganic hybrid nanostructural blocks (Ⅰ).A quantum mechanical investigation for ladder-like structure of vinylsilsesquioxane

The organic/inorganic hybrid nanostructural vinylsilsesquioxanes (VSSO) were prepared from the hydrolytic condensation of vinyltrimethoxysilane (VMS). The proposed formulas of VSSO were assigned with standard spectroscopic techniques, FTIR, NMR (1H, 13C and 29Si) and MALDI-TOF MS, and a generic formula of the SSO, Tn(OH)x(OR')y (x, y = 0, 1, 2...; n =1, 2...; T = RSiO1.s-(x+y)/2n). Geometric parameters (Si-O and Si-C bond lengths, Si-O-Si and O-Si-O bond angles) and total energies of the multi-structures of VSSO were calculated by a quantum mechanical investigation and molecular symmetries. According to the results of the calculation, most molecules had stabler ladder structures than the cage isomers, therefore, the most probably reasonable and optimum structure of the VSSO system was the ladder type.     

Separation and determination of inorganic cations in beverages by capillary electrophoresis with indirect UV detection

A rapid, simple and reliable capillary electrophoresis method for the separation and quantitation of inorganic cations with indirect UV detection at 214 nm was developed. The electrolyte was: 12 mM imidazole as background absorbance provider; 5 mM malic acid and 1.0 mM 18-crown-6 ether as complexing agents; and 20% D₂O (v/v) to improve ion mobility. The pH was 4.25. The applied voltage was 22 kV at 22°C. Nine ions were completely separated and determined with correlation coefficients of 0.9979-0.9992. The relative standard deviations (RSD) were less than 0.5% for migration time and less than 5.2% for peak area (n=8). The detection limits (S/N=3) were from 0.08 mg L⁻¹ (for Na⁺) to 0.51 mg L⁻¹ (for Cu²⁺). To assess the reliability atomic absorption (AA) was also used to determine the same samples. Satisfactory results were obtained for real samples of jasmine tea drink and coconut milk.      

Flow-injection and sequential-injection determinations of paracetamol in pharmaceutical preparations using nitrosation reaction.

A simple FI and two different SI systems have been investigated for the determination of paracetamol by employing a simple reagent for a nitrosation reaction. It is based on the on-line nitrosation of paracetamol with sodium nitrite in an acidic medium. The formed nitroso derivative species reacts further with sodium hydroxide to convert it to a more stable compound. The yellow product is continuously monitored at 430 nm. The FI system is very simple and cost effective for fast manual operation (60 injections/h; y = 0.268x + 44.314, r2 = 0.9910 for 400 - 1000 mg/l and y = 0.1687x + 145.72, r2 = 0.9970 for 1000 - 2500 mg/l). The two SI systems with different components and configurations are automated and optimized for the conditions for which no extra dilution is to be required for sample handling: one with a syringe pump and two selection valves (60 samples/h; y = 0.1488x - 4.7297, r2 = 0.9946 for 400 - 1000 mg/l and y = 0.0858x + 63.933, r2 = 0.9849 for 1000 - 2500 mg/l); the other is simpler and more cost-effective, with an autoburette and only one selection valve (15 samples/h; y = 0.0072x + 1.1467, r2 = 0.9977 for 200 - 1000 mg/l and y = 0.0028x + 5.4699, r2 = 0.9879 for 1000 - 2500 mg/l). They have all been applied to assay paracetamol in pharmaceutical preparations. The obtained results agree with those by the US Pharmacopeia method.     

毛细管电泳多次进样法快速测定尿肌酐

采用毛细管电泳多次进样技术快速测定了尿肌酐。采用３６ｃｍ×５０μｍｉ．ｄ涂层柱,０．１ｍｍｏｌ／ＬｐＨ２．５的磷酸缓冲液,在２００ｎｍ处检测。连续进样５个样品总分析时间为１２ｍｉｎ,比单次进样节省２０ｍｉｎ左右。日内、日间变异系数均小于７．０％,用吡啶作内标,在肌酐浓度为５～８０ｍｇ／Ｌ范围内,肌酐浓度与肌酐同吡啶的峰高比值的线性关系很好（ｒ＝０．９９９６）。测定１２个样品同生化分析仪测定的结果相关性好（ｒ＝０．９７７３）,且分析时间节省了约３０ｍｉｎ。     

Calibration in quantitative analysis: Part 1. General considerations

Mathematical procedures for calibration require assumptions to be made, e.g. the homogeneity of variances and the mathematical relationship between the analyte content x and the signal y. Little is known about the magnitude of errors arising from incorrect assumptions. The variation of the standard deviation of the analytical procedure with the content of the analyte, the selection of the type of mathematical relationship between x and y, and the types of errors made in testing hypotheses are discussed. In certain practical situations, the standard deviation (s.d.) is nearly independent ofx if x < 22p (p = detection limit) and the relative standard deviation (r.s.d.) is nearly independent of x if x > 50p. If the s.d. is constant, calibration relations of the typey = a + bx are frequently to be preferred; with a constant r.s.d.. relations of the type log y = a + b logx have advantages.     

高效液相色谱法测定红茶中的茶黄素

建立了一种用于分析红茶中茶黄素的高效液相色谱法。该方法采用反相C18柱;流动相A为2%醋酸,流动相B为乙腈-乙酸乙酯(体积比为21∶3),梯度洗脱,流速0.8 mL/min;紫外检测波长280 nm;柱温40 ℃;外标法定量。结果表明,所采用的标准曲线有良好的线性关系(r=0.9990~0.9992),加标回收率为96.88%~103.57%,方法的精密度良好(平均RSD<1.5%)。该方法简便、快速、准确,可用于实际样品的测定。     

基于高剪切分散乳化技术的黄芪中黄酮类化合物提取方法及动力学研究

利用高剪切分散乳化(High shear dispersing emulsifier,HSDE)技术为样品前处理方法,以甲醇为提取剂.通过单因素实验、L9(34)正交试验,优选出HSDE提取黄芪中4种黄酮类化合物(毛蕊异黄酮-7-O β-D葡萄糖苷、毛蕊异黄酮、芒柄花素、芒柄花苷)的最佳条件为:料液比1∶20,转速16000 r/min,时间180 s.在此提取条件下进行黄芪提取的动力学研究,结果表明,黄芪中4种黄酮类化合物的HSDE提取过程符合准二级动力学方程特征.以时间(t)为横坐标,时间与峰面积的比值(t/A)为纵坐标,进行线性拟合,方程分别为:毛蕊异黄酮-7-O-β-D-葡萄糖苷:y=0.00974x+ 0.00869,R2=0.99736;毛蕊异黄酮:y=0.00153x+0.01654,R2=0.9862;芒柄化素:y=0.00196x+0.02322,R2=0.98492;芒柄花苷:y=0.00527x+ 0.046,R2=0.99228.在实验的基础上推测其提取机理为气蚀效应、机械效应和剪切效应的协同作用.