Development of a lyophilized soybean paste certified reference material for the analysis of ochratoxin A

A certified reference material (CRM) [²KRISS CRM # 108-10-018] for the analysis of ochratoxin A (OTA) in doenjang (fermented soybean paste and popular food in Korea) was produced to ensure the reliability of analytical results in testing laboratories. A home-made doenjang was chosen as a raw material after testing its OTA level. The raw material was freeze-dried, pulverized, sieved and homogenized. An isotope-dilution-liquid chromatography/tandem mass spectrometric method (ID-LC/MS/MS) which was previously developed and validated in this laboratory was used as a higher-order reference method for characterization, homogeneity studies, and short-term stability studies. The CRM had good between-bottle homogeneity with 0.56% relative standard deviation among 10 selected units. The stability of the CRM at −70 °C (the storage condition in our laboratory) and at −20 °C (the possible storage temperature at user sites) were tested for up to 8 months. No change in the OTA content was observed within the measurement uncertainty. The stability of the CRM at room temperature (for regular use and transportation) was also tested and confirmed. The certified value was (49.50 ± 1.17) μg/kg, where the expanded uncertainty was in the confidence level of 95%.     

Spatially matched in vivo and ex vivo MR metabolic profiles of prostate cancer – investigation of a correlation with Gleason score

MR metabolic profiling of the prostate is promising as an additional diagnostic approach to separate indolent from aggressive prostate cancer. The objective of this study was to assess the relationship between the Gleason score and the metabolic biomarker (choline + creatine + spermine)/citrate (CCS/C) measured by ex vivo high‐resolution magic angle spinning MRS (HR‐MAS MRS) and in vivo MRSI, and to evaluate the correlation between in vivo‐ and ex vivo‐measured metabolite ratios from spatially matched prostate regions. Patients (n = 13) underwent in vivo MRSI prior to radical prostatectomy. A prostate tissue slice was snap‐frozen shortly after surgery and the locations of tissue samples (n = 40) collected for ex vivo HR‐MAS were matched to in vivo MRSI voxels (n = 40). In vivo MRSI was performed on a 3T clinical MR system and ex vivo HR‐MAS on a 14.1T magnet. Relative metabolite concentrations were calculated by LCModel fitting of in vivo spectra and by peak integration of ex vivo spectra. Spearman's rank correlations (ρ) between CCS/C from in vivo and ex vivo MR spectra, and with their corresponding Gleason score, were calculated. There was a strong positive correlation between the Gleason score and CCS/C measured both in vivo and ex vivo (ρ = 0.77 and ρ = 0.69, respectively; p < 0.001), and between in vivo and ex vivo metabolite ratios from spatially matched regions (ρ = 0.67, p < 0.001). Our data indicate that MR metabolic profiling is a potentially useful tool for the assessment of cancer aggressiveness. Moreover, the good correlation between in vivo‐ and ex vivo‐measured CCS/C demonstrates that our method is able to bridge MRSI and HR‐MAS molecular analysis. Copyright © 2012 John Wiley & Sons, Ltd.     

Are risk factors necessary for pretest probability assessment of coronary artery disease? A patient similarity network analysis of the PROMISE trial

BackgroundPretest probability (PTP) calculators utilize epidemiological-level findings to provide patient-level risk assessment of obstructive coronary artery disease (CAD). However, their limited accuracies question whether dissimilarities in risk factors necessarily result in differences in CAD. Using patient similarity network (PSN) analyses, we wished to assess the accuracy of risk factors and imaging markers to identify ≥50% luminal narrowing on coronary CT angiography (CCTA) in stable chest-pain patients.MethodsWe created four PSNs representing: patient characteristics, risk factors, non-coronary imaging markers and calcium score. We used spectral clustering to group individuals with similar risk profiles. We compared PSNs to a contemporary PTP score incorporating calcium score and risk factors to identify ≥50% luminal narrowing on CCTA in the CT-arm of the PROMISE trial. We also conducted subanalyses in different age and sex groups.ResultsIn 3556 individuals, the calcium score PSN significantly outperformed patient characteristic, risk factor, and non-coronary imaging marker PSNs (AUC: 0.81 vs. 0.57, 0.55, 0.54; respectively, p ?< ?0.001 for all). The calcium score PSN significantly outperformed the contemporary PTP score (AUC: 0.81 vs. 0.78, p ?< ?0.001), and using 0, 1–100 and ?> ?100 cut-offs provided comparable results (AUC: 0.81 vs. 0.81, p ?= ?0.06). Similar results were found in all subanalyses.ConclusionCalcium score on its own provides better individualized obstructive CAD prediction than contemporary PTP scores incorporating calcium score and risk factors. Risk factors may not be able to improve the diagnostic accuracy of calcium score to predict ≥50% luminal narrowing on CCTA.     

On the calculation of activity concentrations and nuclide ratios from measurements of atmospheric radioactivity

Motivated by the need for consistent use of concepts central to the reporting of results from measurements of atmospheric radioactivity, we discuss some properties of the methods commonly used. Different expressions for decay correction of the activity concentration for parent–daughter decay pairs are presented, and it is suggested that this correction should be performed assuming parent–daughter ingrowth in the sample during the entire measurement process. We note that, as has already been suggested by others, activities rather than activity concentrations should be used when nuclide ratios are calculated. In addition, expressions that can be used to transform activity concentrations to activity ratios are presented. Finally we note that statistical uncertainties for nuclide ratios can be properly calculated using the exact solution to the problem of confidence intervals for a ratio of two jointly normally distributed variables, the so-called Fieller׳s theorem.     

67Ga显像对活动性肺结核的诊断价值

目的：探讨67Ga显像对活动性肺结核的诊断价值。方法：对160例非肿瘤患67Ga显像结果进行回顾性分析。诊断活动性肺结核100例，陈旧性肺结核26例，普通肺炎29例，淋巴结核5例，结果：活动性肺结核患67Ga阳性显像率72．00％（72／100），明显高于陈旧性肺结核23．08％（6／26）及普通肺炎17．24％（5／29），活动性肺结核患中， 痰菌阳性患67Ga阳性显像率79．73％（59／74），明显高于痰菌阴性50．00％（13／26），结论：67Ga显像可能在判断肺结核活动中具有一定价值。     

After neoadjuvant chemotherapy platelet/lymphocyte ratios negatively correlate with prognosis in gastric cancer patients

Introduction

Circulating predictors prognostic factors of neoadjuvant chemotherapy, which identify the patients who are potential possibly to benefit from it are limited at present. In this research, we aimed to compare the prognostic significance of neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR) in patients with locally advance gastric carcinoma who were treated with neoadjuvant chemotherapy (NAC) followed by D2 gastrectomy.

Materials and methods

From 2007 to 2015, 91 patients with locally advanced gastric cancer treated with NAC followed by D2 gastrectomy included in this retrospective cohort study. The correlation of clinical data, including tumor regression, response evaluation, tumor location, pathological type, systemic therapy, tumor size (cm), neural invasion, lymphatic‐vascular invasion, ypTNM stage, and survival prognosis were analyzed.

Results

Platelet/lymphocyte ratio and neutrophil/lymphocyte ratio in gastric cancer patients were higher than in matched normal volunteers. PLR levels higher after neoadjuvant chemotherapy are associated with worse OS. Multivariate Cox proportional analysis showed that pre‐neoadjuvant chemotherapy PLR was an independent prognostic factor.

Conclusions

Pre‐neoadjuvant chemotherapy PLR may be a feasible biomarker for survival prognosis in patients with locally advanced gastric cancer. PLR and NLR were reduced after neoadjuvant chemotherapy. After neoadjuvant chemotherapy, PLR level was negatively correlated with survival prognosis.

     

A diagnostic approach to different types of non-A non-B acute hepatitis through the evaluation of the lobular distribution of hepatocytic damage

The activity in the serum of three hepatic mitochondrial enzymes, glutamate dehydrogenase (GDH), ornithine carbamyl transferase (OCT) and mitochondrial glutamic oxaloacetic transaminase (m-GOT), all of which show different lobular distribution in the liver, was investigated in order to clarify the usefulness of determinations of these enzymes for the diagnosis of different types of acute non-A non-B (NANB) hepatitis. In NANB hepatitis, there were two different histological types: portal and non-portal. In most portal cases, the GDH/OCT ratios were lower than 0.35, but the ratios were higher than 0.36 in all non-portal cases. The prognosis of the portal group and the short incubation group of NANB hepatitis was better than that of the non-portal and the long incubation group, respectively. The cases showing GDH/OCT ratios of less than 0.35 clearly displayed better prognoses than the cases showing high GDH/OCT ratios. These findings implied that the low GDH/OCT group may have been infected by particular viruses and that ratio determination is useful for the diagnosis of NANB hepatitis caused by different viruses.     

Association of IL-8 gene polymorphisms with non small cell lung cancer in Tunisia: A case control study

Interleukin 8 (IL-8), is a proinflammatory chemokine, has been reported to have angiogenic activity and to be responsible for tumor-associated angiogenesis in several cancers. In this study, we aimed to study the (IL-8) gene polymorphism in relation with risk development of non small cell lung cancer in Tunisian patient. Two single nucleotide polymorphisms (−251T/A [rs4073], +781C/T [rs2227306]) of the IL-8 gene were screened in 170 patients with NSCLC and 225 healthy controls by PCR–RFLP.     

Copolymers of novel methacrylic and styrenic monomer based on the thiophene: synthesis,characterization, monomer reactivity ratios,thermal properties,and biological activity

The free radical copolymerization of 2-thienylmethyl 4-vinylbenzyl ether (TMVBE) with 2-oxo-2-(2-thienylmethoxy)ethyl-2-methylacrylate (TMOEM) has been carried out in 1,4-dioxane at 65?°C?±?1 and were analyzed by Fourier transform infrared, ¹H NMR, and ¹³C NMR spectroscopy. ¹H NMR analysis was used to determine the molar fractions of TMVBE and TMOEM in the copolymers. The monomer reactivity ratios were calculated according to the general copolymerization equation using Kelen–Tüdõs and Finemann–Ross linearization methods. The reactivity ratios indicated a tendency toward alternation copolymerization. The thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa and Kissinger methods with a Shimadzu TGA 60 thermogravimetric analysis thermobalance. All the products showed moderate activity against different strains of bacteria and fungi.