LP(a) phenotypes and levels in angiographically proven coronary heart disease patients and controls

Lipoprotein Lp(a) excess has been identified as a powerful predictor of premature atherosclerotic vascular diseases. To evaluate this in a North-Indian population, 130 CAD patients and 130 controls were analyzed. The size of the apo(a) phenotypic isoforms was inversely proportional to Lp(a) concentrations. The mean concentration of Lp(a) in the CAD patients was 42±34 mg/dl whereas in the normal subjects it was much lower, 27±27 mg/dl. 157 subjects out of the total 260 subjects showed plasma levels of >20mg/dl. The frequency of high Lp(a) levels was much higher in patients(73%) than controls (43%). These data suggest (1) that there is heterogeneity of the Lp(a) polymorphism, (2) Higher Lp(a) levels were found in patients than in the controls, (3) Patients showed 1.5 fold increase in Lp(a) levels as compared to the controls. We conclude that low molecular weight apo(a) isoforms are significantly associated with increased risk of CAD in the North-Indian population.     

Evaluation of triclosan toxic effects on the methanogenic activity

BackgroundTriclosan (TCS) is an antimicrobial agent widely used in health care and consumer products. This compound is present in sludge of wastewater treatment plants (WWTPs), and because of its bactericidal characteristics, it can inhibit the methanogenic activity in anaerobic digestion (AD) technology. The aim of this study was to evaluate the toxic effects of TCS on the methanogenic activity.ResultsBatch anaerobic reactors were used with TCS concentrations of 7.8, 15.7, 23.5, and 31.4 mg/L. These assays consisted in three successive feedings (I, II, and III), wherein the sludge was exposed to each TCS concentration and volatile fatty acid (VFA) substrate. For evaluation of the residual sludge activity during feeding III, only VFA was used. The results showed that the increase in TCS concentrations correlated with the reduction in methane (CH₄) production. In this case, the minimum values were achieved for TCS concentration of 31.4 mg/L with CH₄ levels between 101.9 and 245.3 during feedings I, II, and III. Regarding the effect of TCS on VFA consumption, an inhibitory effect was detected for TCS concentrations of 23.5 and 31.4 mg/L, with concentrations of acetic, butyric, and propionic acids at the end of the assay (37 d) between 153.6 and 206.8, 62.5 and 60.1, and 93.4 and 110 mg/L, respectively. Regarding the removal of TCS during AD, these values were above 47%.ConclusionTCS is an inhibitor of methanogenic activity with a decrease between 63 and 70% during the different feedings. The CH₄ production was not recovered during feeding III, with inhibition percentages of 21–72%.How to cite: Reyes-Contreras C, Leiva AM, Vidal G. Evaluation of triclosan toxic effects on the methanogenic activity. Electron J Biotechnol 2019;39. https://doi.org/10.1016/j.ejbt.2019.03.006.     

A comparison of callus induction in 4 Garcinia species

BackgroundThis research is intended to determine suitable types and concentrations of plant growth regulators (PGRs) to induce callus on stem and leaf sections of 4 species of the genus Garcinia, namely, Garcinia mangostana, Garcinia schomburgkiana, Garcinia cowa, and Garcinia celebica. The base medium was MS medium containing 30 g l^-1 sucrose, 0.5 g l^-1 polyvinylpyrrolidone (PVP), and 7 g l^-1 agar, and for the different treatments, PGRs were added to the medium as follows: thidiazuron (TDZ) at concentrations of 0, 0.1, 0.5, 1, and 2 mg l^-1; 6-(3-hydroxybenzylamino) purine (meta-topolin) at concentrations of 0, 0.5, 2.5, and 5 mg l^-1; 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (picloram) at concentrations of 0, 0.5, 2.5, and 5 mg l^-1; and 2,4-dichlorophenoxyacetic acid (2,4-D) at concentrations of 0, 0.5, 1, 2, and 4 mg l^-1. The occurrence of callus was observed after 4 weeks.ResultsA maximum of 100% and 93% of G. mangostana leaf explants formed callus in the 0.5 mg l^-1 and 1 mg l^-1 TDZ treatments, respectively, while 100% of G. schomburgkiana stem explants formed callus in the 1 mg l^-1 TDZ treatment and 89% of G. schomburgkiana leaf explants formed callus in the 0.5 mg l^-1 picloram treatment. The highest callus induction rate for G. cowa was 62% in the 1 mg l^-1 TDZ treatment and for G. celebica was 56% in the 0.5 mg l^-1·mT^-1 treatment.ConclusionsFor all 4 species, the greatest amount of large nodular callus was observed in the TDZ treatments. White, friable callus was observed on most of the 2,4-D and picloram treatment groups. Most meta-topolin treatments resulted in minimal callus formation.How to cite: Suwanseree V, Phansiri S, Yapwattanaphun C. A comparison of callus induction in 4 Garcinia species. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.006     

纳氏试剂分光光度法测定水中氨氮测量不确定度评定

根据测量不确定度评定与表示理论,采用纳氏试剂分光光度法测定水中氨氨的测量不确定度,通过计算和评定,得出该法测定水是氨氮的测量结果2．88mg／l时,取包含因子k=2（约95％置信概率）,扩展不确定度u=0．092mg／l。该不确定度评价方法在实际工作中具有较强的实用价值。     

Development of biodegradation process for Poly(DL-lactic acid) degradation by crude enzyme produced by Actinomadura keratinilytica strain T16-1

BackgroundPlastic waste is a serious problem because it is difficult to degrade, thereby leading to global environment problems. Poly(lactic acid) (PLA) is a biodegradable aliphatic polyester derived from renewable resources, and it can be degraded by various enzymes produced by microorganisms. This study focused on the scale-up and evaluated the bioprocess of PLA degradation by a crude microbial enzyme produced by Actinomadura keratinilytica strain T16-1 in a 5 L stirred tank bioreactor.ResultsPLA degradation after 72 h in a 5 L bioreactor by using the enzyme of the strain T16-1 under controlled pH conditions resulted in lactic acid titers (mg/L) of 16,651 mg/L and a conversion efficiency of 89% at a controlled pH of 8.0. However, the PLA degradation process inadvertently produced lactic acid as a potential inhibitor, as shown in our experiments at various concentrations of lactic acid. Therefore, the dialysis method was performed to reduce the concentration of lactic acid. The experiment with a dialysis bag achieved PLA degradation by weight loss of 99.93%, whereas the one without dialysis achieved a degradation of less than approximately 14.75%. Therefore, the dialysis method was applied to degrade a commercial PLA material (tray) with a conversion efficiency of 32%, which was 6-fold more than that without dialysis.ConclusionsThis is the first report demonstrating the scale-up of PLA degradation in a 5 L bioreactor and evaluating a potential method for enhancing PLA degradation efficiency.How to cite: Panyachanakul T, Sorachart B, Lumyong S, et al. Development of biodegradation process for Poly(DL-lactic acid) degradation by crude enzyme produced by Actinomadura keratinilytica strain T16-1. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.005     

Comparison of two methods of estimation of low density lipoprotein cholesterol, the direct versus friedewald estimation

Current recommendations of the Adult Treatment Panel and Adolescents Treatment Panel of National Cholesterol Education Program make the low-density lipoprotein cholesterol (LDL-C) levels in serum the basis of classification and management of hypercholesterolemia. A number of direct homogenous assays based on surfactant/solubility principles have evolved in the recent past. This has made LDL-C estimation less cumbersome than the earlier used methods. Here we compared one of the direct homogenous assays with the widely used Friedewald’s method of estimation of LDL-C to see the differences and correlation. We used direct homogenous assay kit to estimate serum LDL-C and high-density lipoprotein cholesterol (HDL-C). Serum Triglyceride (TG) and Total Cholesterol (TC) was estimated and using Friedewald’s formula LDL-C was calculated. The LDL-C level obtained by both methods in 893 fasting serum samples were compared. The statistical methods used were paired t-test and Pearson’s correlation. There was significant difference in the mean LDL-C levels obtained by the two methods at the TG levels <200 mg/dl (p<0.02) and TC levels >150 mg% (p<0.001). The correlation coefficient (r) between Friedewald’s and direct assay estimation was 0.88. Friedewald’s method classified 23.5 % of patients as high cardiac risk whereas there were 17.58% by direct assay. Both had good correlation even though the serum triglyceride and total cholesterol levels affect the difference in LDL-C estimated by both methods. Taking into account the cost and performance, Friedewald’s method is as good or even better for classifying and managing patients.     

Quantification of urinary urate with alkylamine glass-bound uricase and arylamine glass-bound peroxidase

Uric acid in urine was analyzed using porcine liver uricase and horseradish peroxidase immobilized on alkylamine and arylamine glass beads (pore diameter 55nm) respectively. The minimum detection limit was 5.0mg/0.1 ml urine. The recovery of added uric acid was 92%. Within and between assay CVS were <1.3% and <5.3% respectively. A good correlation (r=0.93) was found between urinary urate values obtained by a commercial kit method and the present method. The uric acid in 24hr urine of apparently healthy adults and person sufering from various diseases was found to be 450 to 900mg/24hr, 659mg/24hr (range, mean) and 910–1400mg/24hr, 1145 mg/24hr (range, mean) respectively with the present method.     

Microalbuminuria: An inexpensive,non invasive bedside tool to predict outcome in critically ill patients

This study was conducted to evaluate whether microalbuminuria on admission and after 24 hrs of admission to intensive care unit (ICU) predicts outcome as well as the Acute Physiology and Chronic Health Evaluation (APACHE) II severity illness score, the current accepted method of doing so. The study was carried out in a 20 bed mixed medical-surgical ICU of a tertiary care hospital. Of 525 consecutive adult patients with ICU stay of more than 24 hrs, 238 were included for the study. Patients with pregnancy, menstruation, anuria, macroscopic hematuria, urinary tract infection, marked proteinuria due to renal and post-renal structural diseases, were excluded. Spot urine samples were collected on admission to ICU and 24 hrs thereafter. Urine albumincreatinine ratio (ACR) was measured on ICU admission (ACR1) and after 24 hrs (ACR2) and expressed in mg/g. Patient demographics were noted on admission. For disease severity scoring, APACHE II scores were calculated. Each patient was followed up throughout their ICU stay for a maximum of 28 days and the following outcome data were obtained: ICU length of stay and ICU mortality. Of the 238 patients, 196 survived while 42 patients died in the ICU. Non-survivors had a significantly higher median ACR2 [162.7 mg/g (IQR 69.5–344.3)] in comparison to the survivors who had a median ACR2 = 54.4 mg/g (IQR 19.0–129.1) (P< 0.0001). The median ACR1 [161.0 mg/g (IQR 29.0–369.3)] of non-survivors was higher than the median ACR1 [80.4 mg/g (IQR 35.1–167.6)] of survivors but failed to reach statistical significance (P= 0.0948). In a receiver operating characteristic curve (ROC) analysis, ACR2 emerged as the best indicator of mortality [(area under curve (AUC) of ACR2 = 0.71 > AUC (ACR1) =0.58 > AUC (ΔACR) =0.55] similar to the currently used APACHE II scores (AUC = 0.78) (P=0.3). At a cutoff of 101 mg/g, ACR2 had a sensitivity of 69%, specificity of 67%, positive predictive value of 31% and a negative predictive value of 91% for predicting mortality in the critically ill patients. Absence of significant microalbuminuria at 24 hrs of ICU admission may help to predict survival in the ICU.     

常规石蜡包埋法在改良Golgi银染法中的应用

目的:将常规石蜡包埋法与Golgi银染法结合,改善Golgi银染法的实用性.方法:以新鲜分离的小鼠脑组织作为实验材料,进行火棉胶和常规石蜡包埋,调整其中的脱水,浸腊和包埋等步骤,切片,最后进行银染.结果:改良后的Golgi银染法在采用常规石蜡包埋法条件下,染出清晰神经元图象,并且使用普通切片机就可以实行.结论:采用石蜡...     

The effect of extremely high glucose concentrations on 21 routine chemistry and thyroid Abbott assays: interference study

Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests     

Plasma Voriconazole Estimation by HPLC

Voriconazole, an antifungal drug exhibiting wide inter-individual variability, is an ideal candidate for therapeutic drug monitoring (TDM). The aim of the present study was to standardize a simple, sensitive and rapid high performance liquid chromatography (HPLC) method with ultraviolet detection to determine plasma voriconazole concentration. The HPLC method consisted of a combination of acetonitrile and water (7:3) as mobile phase with 1 ml/min flow rate and detection at 255 nm. Plasma protein precipitation was carried out using perchloric acid and the filtered supernatant was passed through C18 column (250 × 4.6 mm, 5 μm) for the separation of voriconazole. The limit of quantification of voriconazole was 0.2 mg/L. The assay was validated with a linearity of 0.2–15 mg/L and used clinically for TDM in patient samples. The inter-assay precision was below 15 % for routine quality control samples. Weight based voriconazole doses were prescribed to 26 patients for empirical treatment of invasive fungal infections. Voriconazole therapy was managed from the baseline drug levels and follow up analysis reflected achievement in clinical efficacy. Routine TDM of voriconazole may reduce adverse events and improve the treatment response in invasive fungal infections.     

Estimation of glycated hemoglobin by 2,6-dimethylphenol: Sulphuric acid conventional method

Glycated hemoglobin levels in hemolysate of normal and diabetic patients were determined by the 2,6-dimethylphenol:57.5% sulphuric acid conventional method and the values were 0.39±025 and 0.69±0.21 moles of hydroxymethylfurfural(HMF)/mole of globin, respectively. The mean increase in glycated hemoglobin values in diabetics (1.8fold) was highly significant (p<0.001). A good correlation (r=0.95) was found between the glycated hemoglobin values obtained by this method and the phenol:sulphuric acid method. The values obtained by former method were about 1.2–1.4 times the values by the phenol:sulphuric acid method. This study indicates that conventional 2,6-dimethylphenol: 57.5% sulphuric acid method is more sensitive for the estimation of glycated hemoglobin than any other method based on the same principle. It is less time consuming, reliable and hence can be employed for the routine laboratory estimation of glycated hemoglobin for the assessment of glycemic control.     

Preanalytical quality improvement – in quality we trust

Background

The preanalytical phase represents the major source of variability in laboratory diagnostics. Our aim was to assess to what extent underfilling of primary blood tubes may impact upon routine coagulation testing.

Materials and methods:

Blood was drawn by syringe from 21 healthy volunteers and 6 patients on warfarin therapy, and immediately transferred into 3.6 mL vacuum tubes containing 3.2% sodium citrate (Terumo Europe N.V., Leuven, Belgium). All tubes were filled using standardized volumes of whole blood to produce scalar amounts of filling: 3.6 mL (i.e., 100%), 3.2 mL (89%), 2.8 mL (78%) and 2.4 mL (67%). Samples were mixed and centrifuged at 1300 × g for 10 min. The plasma was tested for prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen (FBG) on ACL TOP (Instrumentation Laboratory - IL, Milan, Italy), using IL reagents. A polynomial plot was derived for each parameter from interpolation of clotting values obtained with different percentages of filling, and these plots were compared with quality specifications (± 2.0 for PT, ± 2.3 for APTT and ± 4.8 for FBG) to calculate the minimal filling volume required to produce clinically acceptable results.

Results:

The equations were (PF, Percentage of filling): PT (sec) = 3.375 × PF^2–6.255 × PF + 17.806 (r = 0.980); APTT (sec) = 8.925 × PF^2–23.578 × PF + 46.356 (r = 0.979); and FBG (mg/dL) = −311.5 × PF^2 + 422.1 × PF + 147.07 (r = 0.994). According to these equations, the minimum allowed thresholds of blood tubes filling were > 61% for PT, > 87% for APTT and > 71% for FBG.

Conclusions:

Our results confirm that routine coagulation testing performed on underfilled tubes may generate biased and clinically misleading test results. This is particularly critical for APTT, wherein tubes filled at less than ∼90% generate unreliable data. The FBG and the PT seem more resistant to underfilling, clinical significant biases being observed only where blood tubes were filled at less than ∼60 and ∼70%, respectively.     

基于AHP-BCG矩阵的企业专利战略研究

本文在基于AHP和BCG矩阵的基础上构建专利评价和战略选择模型,首先确定专利的评价指标体系,然后用AHP计算指标体系权重,再结合指标权重建立与BCG矩阵类似的专利评价矩阵,最后制定专利战略.     

A Simple Economical Method for Assay of Atherogenic Small Dense Low-Density Lipoprotein-Cholesterol (sdLDL-C)

In the present study, we report a simple and economical precipitation method for the quantitative determination of small, dense LDL-cholesterol (sdLDL-C) in serum that is considered to be an emerging risk factor for cardiovascular disease. This method consisted of precipitation of lipoproteins of density <1.044 g/ml using heparin-MnCl₂ and quantification of cholesterol existed in the supernatant using reagents for routine cholesterol assay instead of the costly direct low density lipoprotein-cholesterol assay kit. The supernatant contained sdLDL and high-density lipoprotein (HDL) that was confirmed by polyacrylamide gel electrophoresis. sdLDL-C concentration can be calculated by subtracting the HDL-C value from the total cholesterol concentration of the supernatant. sdLDL-C values obtained by this modified method were similar to those obtained by direct assay of sdLDL-C and there was significant correlation between the two methods. In conclusion, this method is highly economical, do not require special equipments and is useful to evaluate atherogenic risk.     

Increasing Glucose Concentrations Interfere with Estimation of Electrolytes by Indirect Ion Selective Electrode Method

The estimation of electrolytes like sodium (Na⁺), potassium (K⁺) and chloride (Cl⁻) using direct and indirect ion-selective electrodes (ISE) is a routine laboratory practice. Interferents like proteins, triglycerides, drugs etc. are known to affect the results. The present study was designed to look into the effect of increasing glucose concentrations on estimation of Na⁺, K⁺ and Cl⁻ by direct and indirect ISE. Pooled sera was mixed with glucose stock solution (20 g/dL) prepared in normal saline to obtain glucose concentrations ranging from ~100 to ~5000 mg/dL. Na⁺, K⁺ and Cl⁻ levels were estimated by direct and indirect ISE analyzers and results were statistically analysed using ANOVA and Pearson’s correlation. Similar experiment was also performed in 24 h urine sample from healthy subjects. Significant difference was observed between Na⁺ and Cl⁻ measurements by direct and indirect ISE, with indirect ISE values being consistently higher than direct ISE. Besides this, significant difference was observed amongst Na⁺ and Cl⁻ values from baseline values obtained by indirect ISE at glucose concentrations ≥2486 mg/dL. However, no such difference was observed with direct ISE. Na⁺ and Cl⁻ estimation by indirect ISE showed significant negative correlation with glucose concentration, more so, above ~2000 mg/dL. K⁺, however, showed no significant difference with varying glucose. Similar results were observed in 24 h urine samples with a significant difference observed amongst Na⁺ and Cl⁻ values at ≥2104 mg/dL glucose. Thus we conclude that high glucose concentrations interfere significantly in estimation of Na⁺ and Cl⁻ by indirect ISE in serum as well as urine.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-015-0522-0) contains supplementary material, which is available to authorized users.     

益母草的染色体数目

Leonurus japonicus Houtt. [L. heterophyllus Sweet, L. artemisia  (Lour.) S.  Y. Hu]  is one of the most important traditional Chinese medicines used as a remedy for gynaeco- logical disease since ancient times.  A cytological investigation on the species was carried out and the materials for chromosomal examination were collected from 26 localities in 20 provi- noes and autonomous regions of this country.  The number of chromosomes in root tip cell of the species was found to be 20 on the whole (Tab. 1:1), agreeing with those reported by Ma and al.[2] and probably by Chuang and al.[3] as well.      The genus Leonurus L. is variable in its  chromosomes with an aneuploidy of x=9, 10 and 12.  The present authors would propose that the primitive basic number of chromosome in the genus is 9, and thus both 10 and 12 are derived, for: (1) among the 9 species (including 1 sub- species) heretofore cytologically examined, x=9 occurring in 66.7%, x=10 occurring in 22.2%, while x=12 occurring only in 11.1%; (2) in generaclosely related to the genus under considera- tion, such as Panzeria, Galeobdolon and Lamium x=9 being the sole basic number.      But L. japonicus exhibits a mixoploidy of 2n=20 (occurring at the rate of 53.30% of the total amount of cells examined), 2n=18 (30.70%), and 2n=16 (15.99%) in our work. (Table 1).  Since the original basic number of  chromosome of the genus is 9 as proposed above, 2n= 20 would be considered as a derived one and the occurrence of 2n=18 probably suggests an early evolutionary trend of 2n=18→20 of the pecies in question.     

中药抚芎的原植物及其与川芎、藁本的比较

The  vegetative  characters of  Ligusticum  chuanxiong  Hort.  cv.  Fuxiong are described in comparison with L. chuanxiong Hort. and L. sinense Oliv. The chromosome numbers and karyotypes of the three taxa were studied in root tip cells by Feulgen’s squash method. Their karyotypes are determined as follows: L. chuanxiong, K(2n)=22=16 m+ 4sm+2st (sat); L. chuanxiong cv. Fuxiong, K(2n)=33=24 m+6sm+3st (sat); L. sinen- se, K(2n)=22=12 m+6sm+2sm (sat)+2st (sat).      The karyotypic similarities are found between L. chuanxiong and its cultivariety, butthe former is a diploid while the latter probably is a homologous triploid.     

科研项目评分程序与方法

定量评分不正确一直是科研项目（课题）评价中存在的大问题。本方法采用先定性排序,后定量评分的程序,增加了评分对课题的重要程序的认识,从而能较容易地把握评分尺度,减少评分的错误。第一步用符号检验法去掉错误数据,按各课题的重要程度排出前后次序;第二步定量评分,新创了用“波动系数平均值”来确定评分值的控制线,在掉落在上下控制线之外的不合理数据,最后到了较为满意的评分结果。该方法基本上解决了课题评分不正确的问题,据验证,正确率从原来的70％左右可提高到95％。它不但适用课题评分,同样也适应其它技术经济评估。