Effect of falciparum malaria infection on blood cholesterol and platelets

The current study is a hospital based investigation, in which attempts were being made to establish the effect of falciparum malarial infection on cholesterol level and platelet counts. The level of parasitaemia and its correlation with cholesterol level and platelet count in malaria patients was investigated. Two hundred clinically diagnosed malaria patients and 200 age matched healthy blood donors were included in the current study. In each case, blood sample was analyzed for serum cholesterol level and platelet count to establish a correlation between such parameters with paraesitemia. Based on the results obtained, it was evident that there was a highly significant reduction in the serum cholesterol level and the platelet count in malaria patients having high levels of parasitaemia. The low levels of cholesterol and platelets in malaria patients provided basis for the possible use of such clinical data in the diagnosis of malaria in the absence of a positive blood film.     

动态液相微萃取-微波衍生化-气相色谱/选择离子检测-质谱法测定毛发中的苯丙胺类毒品

建立了一种便捷的毛发中4种苯丙胺毒品的检测方法。采用动态液相微萃取法用氯仿提取毛发消解液中的苯丙胺类毒品,然后在微波加热的条件下用N-甲基-双三氟乙酰胺(MBTFA)进行衍生化处理,将反应液直接用气相色谱/选择离子检测-质谱法（GC/SIM-MS）检测。以2-甲基苯乙胺为内标,在空白毛发中添加标准品做标准曲线得到4种苯丙胺类毒品的线性相关系数均不小于0.996。衍生化后4种毒品在毛发中的最小检测限(S/N=3)均为50 pg/mg。4种苯丙胺类毒品在毛发中的添加浓度为5 ng/mg时,5次测定的相对标准偏差（RSD）分别为苯丙胺6.0%,甲基苯丙胺13.9%,3,4-(亚甲二氧基)苯丙胺10.2%,3,4(亚甲二氧基)-甲基苯丙胺9.2%。应用所建立的方法对苯丙胺类毒品吸食者的毛发进行检测,检出了这4种毒品,毛发样品的最小用量为4.6 mg (约20 cm 长)。该方法灵敏、简便、快速,可用于毛发中低含量苯丙胺类毒品的分析。     

小鼠血清,全血和鼠毛中的元素含量研究

报告了健康Ｃ５７ＢＬ小鼠血清，全血和鼠毛中９种元素含量。在３种生物样品中测定的元素以鼠毛中含量最高，血清中最低，本文讨论了小鼠和人的血清和毛发元素水平之间的关系，Ｃ５７ＢＬ小鼠作为研究元素和疾病关系的实验动物有其优点。     

Determination of carbamazepine: a comparison of the differential pulse voltammetry (DPV) method and the immunoassay method in a clinical trial

We conducted a clinical trial to analyze human serum containing carbamazepine by using the differential pulse voltammetry (DPV) method with a glassy carbon electrode, and compared it with the fluorescence polarization immunoassay (FPIA). Thirty patients, who visited our hospital to have their serum carbamazepine level checked, were enrolled. Ten mL of venous blood was collected from each patient and analyzed by DPV and FPIA methods. The correlation between the carbamazepine concentrations determined by DPV and FPIA was good, with an RSQ of 0.998. The similarity of the results indicates that these two methods can be used interchangeably. The DPV method using a glassy carbon electrode may be a potential alternative method to determine the carbamazepine level in human serum.     

Amperometric determination of total cholesterol in serum with use of immobilized cholesterol esterase and cholesterol oxidase

Cholesterol esterase and cholesterol oxidase were immobilized on octyl-agarose gel, activated with cyanogen bromide and placed in a reactor. The sensor system for total cholesterol was assembled with the immobilized enzyme reactor, a hydrogen peroxide electrode and a peristaltic pump. Characteristics of the sensor system were investigated by using cholesterol palmitate as a standard substrate. A linear relationship was obtained between peak current and cholesterol palmitate concentration below 1000 mg dl^-1 (10.3 mM). A 10-μl sample could be assayed in 5 min. Total cholesterol in human serum was determined in the range 100–400 mg dl^-1. The standard deviation for the determination of 50 samples of 300 mg dl^-1 was 6 mg dl^-1 (2%). The system was used for 300 assays without loss of enzymatic activity. The correlation coefficient was 0.94 for 27 samples of human sera analyzed by the system proposed and by the conventional chemical method.     

Microanalysis of the antiretroviral nevirapine in human hair from HIV-infected patients by liquid chromatography-tandem mass spectrometry

Sufficient drug exposure is crucial for maintaining durable responses to HIV treatments. However, monitoring drug exposure using single blood samples only provides short-term information and is highly subject to intra-individual pharmacokinetic variation. Drugs can accumulate in hair over a long period of time, so hair drug levels can provide drug exposure information over prolonged periods. We now report on a specific, sensitive, and reproducible liquid chromatography-tandem mass spectrometry method for measuring nevirapine (NVP), a widely used antiretroviral drug, levels in human hair using even a single short strand of hair. Hair samples are cut into small segments, and the drug is extracted in methanol/trifluoroacetic acid (v/v, 9:1) shaken at 37 °C in a water bath overnight, followed by liquid–liquid extraction under alkaline conditions. The extracted samples are then separated on a BDS-C₁₈ column with a mobile phase composed of 50% acetonitrile containing 0.15% acetic acid and 4 mM ammonium acetate with an isocratic elution for a total run time of 3 min and detected by triple quadrupole electrospray multiple reaction mode at precursor/product ion at 267.0 > 225.9 m/z. Deuterated nevirapine-d5 was used as an internal standard. This method was validated from 0.25 to 100 ng/mg using 2 mg hair samples. The accuracies for spiked NVP hair control samples were 98–106% with coefficients of variation (CV) less than 10%. The CV for incurred hair control samples was less than 7%. The extraction efficiency for incurred control hair samples was estimated at more than 95% by repeated extractions. This method has been successfully applied to analyze more than 1,000 hair samples from participants in a large ongoing cohort study of HIV-infected participants. We also showed that NVP in human hair can easily be detected in a single short strand of hair. This method will allow us to identify drug non-adherence using even a single strand of hair.     

Fully automated determination of amphetamines and synthetic designer drugs in hair samples using headspace solid-phase microextraction and gas chromatography-mass spectrometry

This study describes a fully automated procedure using alkaline hydrolysis and headspace (HS) solid-phase microextraction (SPME) followed by on-fiber derivatization and gas chromatographic (GC)-mass spectrometric (MS) detection of amphetamine, methamphetamine, methylendioxyamphetamine, methylendioxymethamphetamine, methylendioxyethylamphetamine, methylendioxyphenylbutanamine, and methylmethylendioxyphenylbutanamine in human hair samples. Ten milligrams of hair is washed with deionized water, petroleum ether, and dichloromethane. After the addition of deuterated internal standards the sample is hydrolyzed with sodium hydroxide and directly submitted to HS-SPME. After the absorption of analytes for an on-fiber derivatization procedure the fiber is directly placed into the HS of a second vial containing N-methyl-bis(trifluoroacetamide) before GC-MS analysis. The limits of detection are determined between 0.01 and 0.17 ng/mg. Absolute analyte recoveries are in the range between 0.3% and 7.5%. Linearity is proven over a range from 0.1 to 50 ng/mg with coefficients of correlation from 0.998 to 1. In comparison with conventional methods of hair analysis, this fully automated HS-SPME-GC-MS procedure is substantially faster and easier to perform without using solvents. It uses minimal sample amounts and has the same degree of sensitivity and reproducibility.     

Determination of blood glucose parameter from human blood serum by using a quartz crystal microbalance sensor coated with phthalocyanines compounds

Determining the blood glucose level is important for the prevention and treatment of diabetes mellitus. We developed a sensor system using Quartz Crystal Microbalance (QCM) to determine the blood glucose level from human blood serum. This study consists of two experimental stages: artificial glucose/pure water solution tests and human blood serum tests. In the first stage of the study, the QCM sensor with the highest performance was identified using artificial glucose solution concentrations. In the second stage of the study, human blood serum measurements were performed using QCM to determine blood glucose levels. QCM sensors were coated with phthalocyanines (Pcs) by jet spray method. The blood glucose values of 96 volunteers, which ranged from 71 mg/dL to 329 mg/dL, were recorded. As a result of the study, human glucose values were determined with an average error of 3.25%.     

Stable (2)H isotope analysis of modern-day human hair and nails can aid forensic human identification

Continuous-flow isotope ratio mass spectrometry (CF-IRMS) was used to compare (2)H isotopic composition at natural abundance level of human scalp hair and fingernail samples collected from subjects worldwide with interpolated delta(2)H precipitation values at corresponding locations. The results showed a strong correlation between delta(2)H values of meteoric water and hair (r(2) = 0.86), while the corresponding correlation for nails was not as strong (r(2) = 0.6). Offsets of -180 per thousand and -127 per thousand were observed when calculating solutions of the linear regression analyses for delta(2)H vs. delta(18)O correlation plots of hair and nail samples, respectively. Compared with the +10 per thousand offset of the global meteoric water line equation these findings suggested that delta(18)O data from hair and nail would be of limited diagnostic value. The results of this pilot study provide for the first time tentative correlations of (2)H isotopic composition of human hair and nails with local water. Linear regression analyses for measured delta(2)H values of human hair and nails vs. water yielded delta(2)H(hair) = 0.49 x delta(2)H(water) - 35 and delta(2)H(nails) = 0.38 x delta(2)H(water) - 49, respectively. The results suggest that (2)H isotopic analysis of hair and nail samples can be used to provide information regarding an individual's recent geographical life history and, hence, location. The benefit of this technique is to aid identification of victims of violent crime and mass disasters in circumstances where traditional methods such as DNA and fingerprinting cannot be brought to bear (or at least not immediately).     

Influence of heavy metals, especially lead, on lipid metabolism, serum alpha-tocopherol level, total antioxidant status, and erythrocyte redox status of copper smelter workers

An assessment of influence of the occupational exposure to heavy metals, especially lead, on serum lipids (including lipid peroxides), total antioxidant status, erythrocyte redox status, and serum alpha-tocopherol level was performed in a group of 141 healthy male copper smelter workers. The following parameters were measured: blood lead and cadmium levels, serum manganese, copper, zinc, calcium and magnesium levels, free erythrocyte protoporphyrins (FEP), total cholesterol, HDL₂-, HDL₃-cholesterol, triglycerides and lipid peroxides in serum, erythrocyte superoxide dismutase (SOD_E), catalase (Cat_E) and glutathion peroxidase (PxGSH_E) activities, erythrocyte reduced glutathione level (GSH_E), serum alpha-tocopherol level, and serum total antioxidant status (TAS). Mean Pb_B was within the norm range (328.2 ± 141.7 μg/L), but mean Mn_S concentration slightly exceeded 10 μg/L (11.04 ± 3.79 μg/L). Mean cholesterol and triglycerides concentrations were near the highest borderline values. We found a significantly negative correlation between lead levels and HDL₃-cholesterol (r = 0.253, P < 0.05). Erythocyte catalase activity and TAS were lowered. TAS showed significant negative correlation with Pb_B. A group of workers with Pb_B≥ 400 μg/L had significantly lower Cat_E, lower TAS, and lower HDL₃-cholesterol, compared to the workers with Pb < 400 μg/L. We have also found positive correlation between alpha-tocopherol and total cholesterol (r = 0.267, P < 0.05) and between alpha-tocopherol and LDL-cholesterol (r = 0.207, P < 0.05).     

高脂饲料对长爪沙鼠血脂和血清电解质的影响

目的观察高脂饲料对长爪沙鼠血清脂质4项和血清电解质K^＋、Na^＋、Cl^-、Ca^2＋、Mg^2＋含量的影响。方法选取雄性长爪沙鼠40只,随机分为两组,分别给予普通饲料和高脂饲料（含1%胆固醇、10%猪油）。喂养12周后颌下静脉丛采血,用日立7180型全自动生化分析仪检测血清TC、TG、HDL-C、LDL-C及Ca^2＋、Mg^2＋含量,用美国Easy Lyte Plus型电解质分析仪检测血清K^＋、Na^＋、Cl^-含量。结果与正常饲料组相比,高脂饲料喂养后沙鼠血清TC、TG、HDL-C、LDL-C含量显著升高（P〈0.01）,以TC、LDL-C水平升高最为明显。沙鼠血清电解质K^＋、Mg^2＋含量在不同饲料组差异有显著性（P〈0.01或P〈0.05）,而Na^＋、Cl^-、Ca^2＋含量在不同饲料喂养组的差异不显著（P〉0.05）。结论高脂饲料能明显升高长爪沙鼠血清脂质4项,并改变其血清电解质K^＋、Mg^2＋水平。     

Determination of total cholesterol in serum by high-performance liquid chromatography with electrochemical detection

A simple and sensitive HPLC method that does not require derivatization for determining cholesterol has been developed. Investigation of voltammetric behavior of cholesterol showed that cholesterol could be oxidized on a glassy carbon electrode in non-aqueous solvents. This was applied to the development of a method by HPLC with electrochemical detection (HPLC-ED). The HPLC-ED was optimized using the separation of cholesterol and oxysterols including 26-hydroxycholesterol and 24S-hydroxycholesterol. The separation was carried out with a Develosil C30-UG-3 column; acetonitrile-2-propanol (9:1, v/v) containing 50mM LiClO(4) as a mobile phase; and an applied potential at 1.9V versus Ag/AgCl. The current peak height was linearly related to the amount of cholesterol injected from 0.5-100 microM (r>0.999). The detection limit (S/N=3) of cholesterol was 0.36 microM (1.8 pmol). Cholesterol at 100 microM was directly detected with a relative standard deviation (RSD) of less than 1.0% (n=8). Total cholesterol and free cholesterol in control human serum were determined by the present method with the recovery of more than 90% and the RSD (n=6) of less than 3.0%.     

Assessment of serum cholesterol by two methods: gas-liquid chromatography on a capillary column and chemical ionization-mass fragmentography with isotopic dilution of [3,4-13C] cholesterol as internal standard.

A gas-liquid chromatographic (GLC) method and an isotopic dilution-mass fragmentographic (ID-MF) procedure using the same capillary chromatographic separation are described for serum cholesterol assay. GLC included silylation and separation on a highly efficient glass capillary column which allowed the separation of cholesterol from cholestanol and the use of epicoprostanol as internal standard. The concentrations were calculated from the areas of the signals and digitalized by a reporting integrator. The reproducibility was 0.5% and the correlation with the ID-MF technique was 0.997. The ID-MF technique was characterized by the use of [3,4-13C] cholesterol as the labelled standard and a chemical ionization mode. The reproducibility was 0.8%.     

人血清与头发中铜,锌,铁,钙,镁,锰含量的相关分析

平行测定了５４例（男３１例，女２３例）成人血清和头发中铜，锌，铁，钙，镁和锰的含量，相关分析结果表明，血清与头发中６种元素的不相关两类样品比较，血清测定方法简便，误差小，但在检测人体内元素含量水平时，头发的测量结果比血清更灵敏。     

Microcalorimetric Determination of Serum Triglycerides and Cholesterol

Abstract

Reaction heats measured in a microcalorimeter between varying amounts of human serum and 700 IU of lipase (EC 3.1.1.3) and those between serum and 8 U of cholesterol oxidase (EC 1.1.3.6) were significantly linear with the contents of triglycerides (r=1.00) and cholesterol (r=0.99), respectively. However, when sera from 13 human volunteers were subject to comparative study between the micro-calorimetric and spectrophotometric methods, the correlation became less appreciable (r=0.70 and r=0.71) presumably due to the individual variations in free glycerol and cholesterol ester-constituents that were deliberately omitted in the microcalorimetric method but were routinely included in the standard (multi-enzymatic) spectro-photometric clinical method. The contribution of interfering substances, if any, is not totally ruled out.     

Homeostasis as regulated by activated macrophage. VII. Suppression of serum cholesterol level by LPSw (a lipopolysaccharide from wheat flour) in WHHL (Watanabe heritable hyperlipidemic) rabbit.

The effect of LPSw (a lipopolysaccharide from wheat flour) on cholesterol catabolism was examined using WHHL (Watanabe heritable hyperlipidemic) rabbit, which is an experimental model of familial hyperlipidemia. The serum cholesterol level of the animal decreased by the addition of LPSw to drinking water. Following cessation of the addition of LPSw to the drinking water, the cholesterol level was decreased for 30 to 40d and then gradually elevated. The serum level of apolipoprotein B, which is a constituent of apolipoprotein of low density lipoprotein (LDL), also decreased in accord with serum cholesterol at a nearly coincident rate. Conversely, the level of apolipoprotein A-I, which is a constituent of apolipoprotein of high density lipoprotein (HDL), did not change, nor did HDL-cholesterol. Furthermore, the atherosclerosis risk factor, expressed as the ratio of apolipoprotein B to apolipoprotein A-I, was decreased by LPSw administration.     

Quantitative determination of clozapine in serum by instrumental planar chromatography

An instrumental planar chromatographic (HPTLC) method for quantitative analysis of clozapine in human serum was developed and validated. Clozapine was extracted with n-hexane-isoamyl alcohol (75:25 v/v). The chromatographic separation was achieved on precoated silica gel F 254 HPTLC plates using a mixture of chloroform and methanol (9:1 v/v) as mobile phase. Quantitative analyses were carried out by densitometry at a wavelength of 290 nm. The method was linear between 10 and 100 ng/spot, corresponding to 0.10 and 1.00 ng/microL of clozapine in human serum after extraction process and applying 10 microL to the chromatographic plates. The method correlation coefficient was 0.999. The intra-assay variation was between 2.10 and 3.33% (n = 5) and the interassay was between 2.67 and 4.44% (n = 9). The detection limit was 0.03 ng/microL, and the quantification limit was 0.05 ng/microL. The method proved to be accurate, with a recovery between 97.00 and 99.00%, with an RSD not higher than 7.22%, and was selective for the active principle tested. This method was successfully applied to quantify clozapine in patient serum samples. In conclusion, the method is useful for the quantitative determination of clozapine in serum.     

Voltammetric determination of cholesterol in human blood serum

Cholesterol has a number of important functions in a human body. The disorders of cholesterol biosynthesis increase the risk of the development of cardiovascular diseases and worsens the function of the immune system. This study is devoted to the development of a method for determining the concentration of cholesterol in blood serum using voltammetry. We selected the following working conditions for the determination of cholesterol: a phosphate buffer solution with pH 6.86 was a supporting electrolyte; potential sweep rate was W = 30 mV/s; and recording was carried out in the constant-current mode. An organomodified electrode was used as a working electrode. The peak was observed at +0.98 V. The dependence of the electrooxidation current of cholesterol on its concentration was linear in the range of 0.1–50 μM with a limit of detection of 0.01 μM. The results of the determination of cholesterol in blood serum by voltammetry were compared to those obtained by the fluorimetric method.     

Sensitive analysis of anti-HIV drugs, efavirenz, lopinavir and ritonavir, in human hair by liquid chromatography coupled with tandem mass spectrometry

A highly sensitive and selective method using liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) was developed and validated for the measurement of three antiretroviral agents, efavirenz, lopinavir and ritonavir, in human hair. Hair samples from adherent HIV-infected patients on antiretroviral therapies were cut into about 1 mm length segments and drugs were extracted by first shaking the samples with methanol in a 37 degrees C water bath overnight (>14 h), followed by methyl tert-butyl ether/ethyl acetate (1:1) extraction under weak alkaline conditions. The extracted lopinavir and ritonavir were separated by reversed-phase chromatography and detected by tandem mass spectrometry in electrospray positive ionization mode with multiple reaction monitoring (MRM), while efavirenz was monitored in negative ionization MRM mode. This method was validated from 0.01 to 4.0 ng/mg hair for ritonavir and 0.05-20 ng/mg hair for lopinavir and efavirenz by using 2 mg of a human hair sample. The interday and intraday assay precision (coefficients of variation, CV) for spiked quality control (QC) samples at low, medium and high concentrations were within 15% and accuracy ranged from 89% to 110%. Assay reproducibility was also demonstrated by analysis of incurred hair QC samples (CV <14%). No significant matrix ionization suppression was observed. This developed method allowed for the monitoring of these target medications in the hair samples of HIV-infected women on antiretroviral therapy in an observational study using small amounts of hair.     

Influence of heavy metals, especially lead, on lipid metabolism, serum alpha-tocopherol level, total antioxidant status, and erythrocyte redox status of copper smelter workers

An assessment of influence of the occupational exposure to heavy metals, especially lead, on serum lipids (including lipid peroxides), total antioxidant status, erythrocyte redox status, and serum alpha-tocopherol level was performed in a group of 141 healthy male copper smelter workers. The following parameters were measured: blood lead and cadmium levels, serum manganese, copper, zinc, calcium and magnesium levels, free erythrocyte protoporphyrins (FEP), total cholesterol, HDL₂-, HDL₃-cholesterol, triglycerides and lipid peroxides in serum, erythrocyte superoxide dismutase (SOD_E), catalase (Cat_E) and glutathion peroxidase (PxGSH_E) activities, erythrocyte reduced glutathione level (GSH_E), serum alpha-tocopherol level, and serum total antioxidant status (TAS). Mean Pb_B was within the norm range (328.2 ± 141.7 μg/L), but mean Mn_S concentration slightly exceeded 10 μg/L (11.04 ± 3.79 μg/L). Mean cholesterol and triglycerides concentrations were near the highest borderline values. We found a significantly negative correlation between lead levels and HDL₃-cholesterol (r = 0.253, P < 0.05). Erythocyte catalase activity and TAS were lowered. TAS showed significant negative correlation with Pb_B. A group of workers with Pb_B≥ 400 μg/L had significantly lower Cat_E, lower TAS, and lower HDL₃-cholesterol, compared to the workers with Pb < 400 μg/L. We have also found positive correlation between alpha-tocopherol and total cholesterol (r = 0.267, P < 0.05) and between alpha-tocopherol and LDL-cholesterol (r = 0.207, P < 0.05). Received: 28 July 1997 / Revised: 6 November 1997 / Accepted: 4 November 1997