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Abstract: A highly sensitive DNA biosensing method down to sub-femtomolar level with excellent selectivity was proposed by designing an amplified synthesis of horseradish peroxidase mimicking DNAzyme and introducing the amplified DNAzyme to chemiluminescent (CL) imaging. The amplified synthesis was achieved by combining a target DNA related ligase reaction with rolling circle amplification (RCA), which produced thousands of repeated sequences to bind hemin and form a mass of horseradish peroxidase-mimicing DNAzyme units. The amplification strategy greatly enhanced the CL emission of the luminol–H2O2 system. The genotyping method displayed highly specific biochemistry in allele discrimination. The novel CL imaging strategy based on ligation-mediated RCA synthesis of DNAzyme showed high fidelity in discriminating single-base mismatch and efficiently facilitated signal amplification for sensitive target DNA detection. It could detect DNA ranging from 1×10−15 M to 1×10−11 M with a detection limit of 0.26fM. The proposed approach provided a robust, cost-efficient, highly sensitive and specific platform for genetic target analysis in bioanalysis and clinic biomedical application. [Copyright &y& Elsevier]

Background: In cancer patients, including women with a diagnosis of ovarian cancer, cancer antigen 125 (CA125) is used to evaluate the presence of peritoneal involvement. The aims of the present study were to assess CA125 reference intervals and reference change values (RCV) in postmenopausal reference women, postmenopausal women breast cancer free, reference men and cancer free men. Methods: The series consisted of 433 subjects: 105 postmenopausal breast cancer free women and 56 cancer free men in addition to a total of 272 reference subjects (145 postmenopausal women and 127 men). Repeated CA125 measurements were made in a subset of 149 women and 54 men to calculate RCV and index of individuality. Serum CA125 levels were evaluated by a chemiluminescent assay. Results: In postmenopausal reference women, the mean CA125 value and 2.5th-97.5th percentiles were 6.70, 2.60-11.00 kU/L, respectively, with a unidirectional RCV of 38.4%. In postmenopausal breast cancer free women, the mean CA125 value and 2.5th-97.5th percentile were 7.45, 4.09-10.92 kU/L, respectively, with a RCV of 34.5%. The difference between the means was statistically significant (t=-3.02, p=0.003). In the two male subgroups, the difference between the means for CA125 was not statistically significant (t=0.43, p=0.665). On considering the entire male population, the mean CA125 value and 2.5th-97.5th percentiles were 7.50 and 2.40-13.2 kU/L, respectively, while the unidirectional RCV was 34.3%. In all the studied groups, the indices of individuality were equal to or below 0.6. Conclusions: The extremely low index of individuality found underlines the importance of using the RCV instead of absolute values as a parameter when interpreting the CA125 data in the monitoring and follow-up of patients with ovarian cancer. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to evaluate the diagnostic performance of PSA-based parameters in prostate cancer (PCa) and benign prostatic hyperplasia (BPH) and to determine the relation between serum PSA and histopathological grade in PCa. Methods: This retrospective study includes data of 320 patients with PCa (n: 155) and BPH patients (n: 165). Serum PSA levels and Gleason scores of patients were determined by examining the records of Clinical Biochemistry and Pathology Laboratory. We classified the patients according to total PSA (tPSA) levels to determine diagnostic performance of PSA-based parameters at different cut-off levels. Serum tPSA, free PSA (fPSA) and complexed PSA (cPSA) were analyzed with chemiluminometric method. Results: There were significant differences between BPH and PCa patients in tPSA, fPSA, cPSA and f/tPSA values (p<0.05) in whole group (WG). There were significant differences between BPH and PCa patients in cPSA and f/tPSA in group with tPSA<4 ng/mL (LG); in f/tPSA values in group with tPSA 4-10 ng/mL (intermediate group, IG). According to histopathological classification, all of the parameters except f/tPSA were significantly different between groups in PCa (p<0.001). Significant positive correlations were found between Gleason scores and tPSA (r=0.577), fPSA (r=0.491) and cPSA (r=0.562) (p<0.001). Conclusion: We suggest the use of f/tPSA to improve the differentiation of BPH and PCa in IG. The best cut-off points for tPSA, fPSA, cPSA and f/tPSA were 4.0, 2.21, 3.16 ng/mL and 0.17 respectively. Based on the results of ROC analysis, a cut-off value of 0.17 for f/tPSA and 3.16 ng/mL for cPSA may be acceptable. [ABSTRACT FROM AUTHOR]

A highly sensitive chemiluminescent immunoassay (CLIA) using a sensitive organic photodetector was developed to detect human cortisol, an important biomarker for stress-related diseases. The developed CLIA was performed onto gold-coated glass chips, on which anti-cortisol antibodies were immobilised and chemiluminescent horseradish peroxidase-luminol-peroxide reactions were generated. Using cortisol-spiked artificial saliva samples, the CLIA biosensor showed a linear range of detection between 0.1 ng/mL and 175 ng/mL and a detection limit of 80 pg/mL. The sensor response was highly specific to cortisol and did not vary significantly between assays. The results indicate the potential clinical application of the CLIA sensor. Furthermore, the simple layered structure of the organic photodetector may encourage the realisation of integrated optical biosensors for point-of-use measurement of salivary cortisol levels. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the prognostic value of pretherapeutic serum HE4 in endometrial cancer in comparison to CA125. Methods: HE4 and CA125 serum levels were analyzed by means of chemiluminescent microparticle immunoassays in 183 patients with endometrial cancer treated at the Department of Obstetrics and Gynecology, Innsbruck Medical University, between 1999 and 2009. The Kaplan–Meier method and Cox''s proportional hazards analysis were performed to determine the prognostic significance of HE4, CA125 and the combination of both markers. Results: In univariate analysis both markers, HE4 and CA125, were of prognostic value for overall survival (p<0.001 and p=0.028) and disease-free survival (p=0.015 and p=0.045). In multivariate analysis HE4 was seen to have independent prognostic value in overall survival (HR 2.407, p=0.017) in contrast to CA125. The combination of both markers showed a higher hazard ratio (HR 4.04, p=0.023) for overall survival in comparison to HE4 alone. In the subgroup endometrioid histological type (n=132) only HE4 was of prognostic value for overall survival in univariate (p=0.001) and multivariate analysis (p=0.023). Conclusions: Pretherapeutic serum HE4 levels alone and in combination with CA125 are an independent prognostic marker in endometrial cancer patients. [Copyright &y& Elsevier]

A competitive indirect chemiluminescent enzyme-linked immunoassay (CL-ELISA) for chloramphenicol (CAP) residues in milk and chicken muscle has been developed. Due to the unique characteristic of the polyclonal antibody, special reaction system and modified extract method, then after optimization (concentration of Tween-20, concentration of PB and pH, incubation time, and temperature), the method gave a detection limit of 0.92 ng/L and a detection range of 3.16–3035 ng/L, with the IC50 of 17.29 ng/L in optimum condition and real sample matrix. When CAP was spiked in milk and chicken muscle at levels of 5–100 ng/L, recoveries ranged from 104.9%–114.8% and 101.0%–118.8%, with coefficients of variation of 3.0%–14.6% and 9.5%–14.4%, respectively. In an actual chicken muscle residue study, although the extract of samples diluted 10-fold, or even 100-fold, which represents extremely lower concentration of CAP, the results obtained by CL-ELISA correlated well with those obtained by gas chromatography with microcell electron capture detector. The developed method is therefore suitable for screening of ultratrace CAP residues in milk and chicken muscle samples. [ABSTRACT FROM AUTHOR]

ABSTRACT Background and objective: Measurement of the fraction of nitric oxide (FeNO) in exhaled air is useful in the management of asthma. A new hand-held nitric oxide (NO) analyzer, the NIOX MINO, is simple and easy to use in clinical practice. In this study, FeNO values measured using the NIOX MINO were compared with those obtained using a stationary chemiluminescence analyzer, the Sievers NOA280i. Methods: FeNO was measured in 100 adults, using both the NIOX MINO and the NOA280i. Nine (9.0%) of these subjects had asthma. The first acceptable measurement with the NIOX MINO and the mean of two acceptable measurements with the NOA280i were compared. Results: There was a significant correlation between FeNO concentrations measured with the two devices ( r = 0.876, P < 0.001). A Bland-Altman plot showed a high degree of agreement between the two devices: the mean inter-device difference was 3.3 parts per billion (ppb), and the 95% limits of agreement were −7.0 and 13.6 ppb. In addition, the mean relative difference was 14.5%, with the 95% limits of agreement being −33.7 and 62.7%. The mean value (± standard error of the mean) for FeNO as measured with the NIOX MINO (18.8 ± 0.9 ppb) was significantly lower than that measured with the NOA280i (22.1 ± 1.2 ppb, P < 0.001). Conclusions: There was a significant correlation, but only moderate agreement, between FeNO values measured with the NIOX MINO and those measured with the NOA280i, with the NIOX MINO values being significantly lower than the NOA280i values. Significant differences in FeNO values obtained with these two NO analyzers should be considered when interpreting the results of FeNO measurements. [ABSTRACT FROM AUTHOR]

In this study, we compared plasma levels and the diagnostic utility of hematopoietic growth factors (HGFs) with SCC-Ag in cervical cancer patients in relation to control groups and cervical intraepithelial neoplasia (CIN) patients and healthy subjects. Pretreatment plasma levels of HGFs (SCF, GM-CSF, G-CSF and M-CSF) were determined by the use of immunoenzyme assay (ELISA), and SCC-Ag by chemiluminescent microparticle immunoassay (CMIA). Significantly different concentrations of GM-CSF, G-CSF and M-CSF were observed in the group of patients with cervical cancer and CIN compared to the healthy controls. Significant differences in plasma levels of GM-CSF and M-CSF between cervical cancer and benign lesions patients were also found. The HGFs and SCC-Ag diagnostic specificities received high values. The diagnostic sensitivity and the predictive value of a positive and negative test result were higher for M-CSF than for antigen SCC in the cancer group. The M-CSF area under the ROC curve (AUC) was the largest from hematopoietic cytokines and SCC-Ag. These results suggest the potential utility of M-CSF as a good candidate for a marker of cervical cancer as well as benign lesions of this organ (CIN). [ABSTRACT FROM AUTHOR]

Long-term sample storage can affect the intensity of the hybridization signals provided by molecular diagnostic methods that use chemiluminescent detection. The aim of this study was to evaluate the effect of different storage times on the hybridization signals of 13 bacterial species detected by the Checkerboard DNA-DNA hybridization method using whole-genomic DNA probes. Ninety-six subgingival biofilm samples were collected from 36 healthy subjects, and the intensity of hybridization signals was evaluated at 4 different time periods: (1) immediately after collecting ( n = 24) and (2) after storage at -20 °C for 6 months ( n = 24), (3) for 12 months ( n = 24), and (4) for 24 months ( n = 24). The intensity of hybridization signals obtained from groups 1 and 2 were significantly higher than in the other groups ( p < 0.001). No differences were found between groups 1 and 2 ( p > 0.05). The Checkerboard DNA-DNA hybridization method was suitable to detect hybridization signals from all groups evaluated, and the intensity of signals decreased significantly after long periods of sample storage. [ABSTRACT FROM AUTHOR]

The article discusses a continuing professional education (CPD) paper on regular oral cancer screening. It states that early detection of oral malignant and premalignant lesions increase survival of patients. Different screening techniques including adjunctive visual screening, chemiluminescent illumination, and toluidine blue staining are also discussed.

Abstract: Objectives: To examine the relationship of serum 25-hydroxy vitamin D3 with cognitive functioning in higher age, using an instrument covering multiple cognitive domains in a population-based study. Design: Follow-up study with measurement of vitamin D levels at baseline and assessment of cognitive functioning at year 5 follow-up. Setting and participants: A subgroup of 1639 participants of the ongoing epidemiological ESTHER study of the elderly general population in Saarland State, Germany, aged 65+ years at baseline (2000–2002). Intervention: Observational study. Measurements: Cognitive functioning was assessed by the COGTEL phone interview developed by Kliegel et al., which was administered 5years after ESTHER baseline. Vitamin D in baseline samples was measured by chemiluminescence methods. Additional information was obtained by standardised questionnaires. Results: In multiple linear regression adjusted for important confounders, women in the lowest sex-specific quintile of vitamin D showed an on average 2.1 (95% confidence interval: 0.4 to 3.9) units lower COGTEL score than women in the highest quintile. A similar, albeit slightly weaker, association was seen in males (difference of 1.7 [−0.4 to 3.8] units). Spline regression suggested non-linearity with a distinct decline in cognitive performance in the lower range of vitamin D levels. Conclusions: Our findings support suggestions that low levels of vitamin D may be associated with reduced cognitive functioning in the elderly. [Copyright &y& Elsevier]

The electrochemistry of several difluoroboradiaza-s-indacene (BODIPY) compounds lacking substituent groups in the meso (8)- and/or 3 (α)-positions was investigated. Chemical and electrochemical dimerization was demonstrated, and the dimerization depended on the character of substitution. The chemical dimerization was achieved by oxidative coupling using FeCl3 in CH2Cl2 at 0 °C. The electrochemical dimerization proceeded via anodic oxidation to the radical cation and monitored by both cyclic voltammetry (CV) and electrogenerated chemiluminescence (ECL). An available open 3-position was important for the formation of the dimer. The resulting 3,3′-dimer produced a second peak in the CV oxidation and also the appearance of a longer wavelength ECL peak at 656 nm, which is considerably shifted from the parent peak at 532 nm. No dimerization was seen for BODIPY molecules in which only the meso 8-position was unsubstituted, either by chemical or electrochemical means, demonstrating that dimerization occurs at position 3. [ABSTRACT FROM AUTHOR]

Abstract: Background: The soluble CD14 subtype (sCD14-ST: renamed as presepsin) is a novel soluble CD14 molecule that is useful for diagnosing sepsis because sCD14-ST levels increase specifically in sepsis patients. Methods: A fully automated PATHFAST® Presepsin assay system based on a chemiluminescent enzyme immunoassay was developed for detecting presepsin in human whole blood. Results: The limit of blank, limit of detection, and limit of quantification were 2.33, 13.4, and 47.6pg/ml, respectively. The assay linearity was achieved up to 20,000pg/ml. Intra-assay imprecision was 3.4–4.8% for plasma and 2.7–7.1% for whole blood. Within-run imprecision and total imprecision for plasma were 3.6–4.4% and 5.2–6.5%, respectively. No interference was observed with bilirubin, hemoglobin, lipids, triglyceride, or rheumatoid factors. The reference intervals (95% percentile, n=127) were 333pg/ml for plasma and 314pg/ml for whole blood. The PATHFAST® Presepsin assay correlated well with a previously reported two-step presepsin ELISA (r=0.984, n=40). Furthermore, the concentration of presepsin was significantly higher in the sepsis group than in the healthy group. Conclusion: The PATHFAST® Presepsin assay performed well and can be used for point-of-care. [Copyright &y& Elsevier]

A novel method is described for simultaneous detection and quantification of attomoles or a few femtomoles of two (or potentially more) nucleic acid targets, without need for amplification. The technique depends on spectral-temporal resolution of chemiluminescence emitted from independent hybridization-induced chemiluminescent signal probes. The probes are internally quenched except in the presence of their specific targets, thereby allowing detection limits up to 10?000 times lower than with fluorescent probes. This is sufficient to obviate the need for amplification in many cases. The utility of the technique has been demonstrated by use of resolvable N-linked acridinium and 2,7-dimethoxyacridinium ester labeled probes in a homogeneous assay for sensitive and simultaneous independent quantification of pan-bacterial and pan-fungal target sequences in seawater. [ABSTRACT FROM AUTHOR]

Summary Objective Serum free cortisol, rather than serum total cortisol (TC), determines glucocorticoid activity in vivo, but how the considerable inter-subject variation in ambient serum free cortisol affects the outcome of dynamic hypothalamic-pituitary-adrenal (HPA) assessment in noncritically ill subjects is unknown. Design, patients and measurements We performed the low-dose 1-μg ACTH test in 75 subjects referred for HPA evaluation. Serum TC was determined by a chemiluminescence method, and serum free cortisol was measured by the same method following equilibrium dialysis. In a subset of these patients, salivary cortisol was also measured. Results Mean fraction of free cortisol was 5·07 ± 4·08% (±SD; range 1·77-10·1%). Although no correlation was seen between TC and the fraction (%) of free serum cortisol, a positive correlation existed between baseline total and free cortisol ( R = 0·539 P = 0·01), as well as between peak ACTH-stimulated total and free cortisol ( R = 0·619; P = 0·01). There was no correlation between baseline salivary cortisol and serum free cortisol and between peak ACTH-stimulated salivary and serum free cortisol. Using the lowest attained peak serum free cortisol in subjects whose TC response to ACTH was normal (≥500 n m), the minimal 'pass' level for normal serum free cortisol response to 1 μg ACTH was set at 25·0 n m. Five of the 19 subjects showing subnormal TC response to 1 μg ACTH had normal serum free cortisol response. Conclusions Discrepancies between the peak free and TC were noted mostly for subjects whose ACTH-stimulated TC peaked between 440 and 580 n m. At this range, the measurement of serum free cortisol allows further refinement of the assessment of borderline responses to 1-μg ACTH. [ABSTRACT FROM AUTHOR]

Abstract: We report in this manuscript, the use of direct ammonium persulfate-enhanced chemiluminescence (CL) imaging, to monitor changes to measure serum salbutamol concentration in subjects of different haptoglobin (Hp) phenotypes at different dosing time. It was noted that CL generated from Hp was decreased due to salbutamol''s reducibility, which was used for monitoring salbutamol concentration in serum. The serum from the subjects treated by oral administration of salbutamol, was collected at different dosing time and was separated by polyacrylamide gel electrophoresis (PAGE) prior to the CL detection. According to CL images, samples were separated into three groups based on the Hp phenotypes. The curves of CL signal intensity versus time were obtained for each group, and we demonstrated that there were more significant variables on binding ability between groups. The maximum salbutamol concentration in the serum appeared after 4h, which was in agreement with the literature. In addition, the binding constants of salbutamol to Hp were determined by a fluorescence-based method, whose results were in agreement with the phenomenon of the greater salbutamol metabolism rate for Group Hp 1-1 than Group Hp 2-2. The presented method can monitor changes of salbutamol concentration in serum directly, making the procedures much simple, convenient, rapid and has the property of lower cost. It provided us with excellent reference information for the individual dosage regimen of different Hp groups, which hopefully could become a potential method for further pharmaceutical research. [Copyright &y& Elsevier]

Vitamin D deficiency could be associated with the prevalence of atopic dermatitis (AD). We carried out a study to see whether deficient/insufficient levels of vitamin D correlate with the severity of atopic skin disease. Using the SCORAD index, we evaluated the severity of disease in 37 children (17 girls and 20 boys) aged between 8 months and 12 years with AD, consecutively enrolled in the study. Serum levels of 25-hydroxyvitamin D [25(OH)D] were determined by a chemiluminescent method. Specific IgE (sIgE) to Staphylococcus aureus enterotoxins and sIgE to Malassezia furfur were assayed by the ImmunoCAP system. and the Pearson correlation test were used for statistical evaluation. We found severe, moderate and mild AD in nine (24%), 13 (35%) and 15 (41%) children, respectively. Mean ± SD serum levels of 25(OH)D were significantly higher ( P < 0·05) in patients with mild disease (36·9 ± 15·7 ng mL) compared with those with moderate (27·5 ± 8·3 ng mL) or severe AD (20·5 ± 5·9 ng mL). The prevalence of patients with sIgE to microbial antigens increased in relation to vitamin D deficiency and AD severity. These data suggest that vitamin D deficiency may be related to the severity of AD and advocate the need for studies evaluating the use of vitamin D as a potential treatment in patients with this disease. [ABSTRACT FROM AUTHOR]

Abstract: The qualitative and semiquantitative Western blotting technique enables the detection of separate proteins and the determination of subtypes and fragments by specific immunological reactions. Protein typing on immunoblots is restricted to antibody-specific determination, with the result of a specific banding pattern. For protein characterization, several antibodies that recognize different epitopes within the protein sequence are used. However, repeated or parallel gel runs are needed. Here we describe a sequential determination of prion proteins in healthy and pathological states that both consist of di-, mono-, and nonglycosylated isoforms using a single blot with two antibodies from two species that recognize one antigen with two epitopes. The band signals are visualized by using different chemiluminescent substrate reactions. This application can be used in the fields of diagnostics and public health to detect full-length and fragmented proteins and can also be used for characterization of overlaying proteins. [Copyright &y& Elsevier]

Imaging techniques are a vital part of clinical diagnostics, biomedical research and nanotechnology. Optical molecular imaging makes use of relatively harmless, low-energy light and technically straightforward instrumentation. Self-illuminating, chemiluminescent systems are particularly attractive because they have inherently high signal contrast due to the lack of background emission. Currently, chemiluminescence imaging involves short-lived molecular species that are not stored but are instead generated in situ, and they typically emit visible light, which does not penetrate far through heterogeneous biological media. Here, we describe a new paradigm for optical molecular imaging using squaraine rotaxane endoperoxides, interlocked fluorescent and chemiluminescent dye molecules that have a squaraine chromophore encapsulated inside a macrocycle endoperoxide. Squaraine rotaxane endoperoxides can be stored indefinitely at temperatures below −20 °C, but upon warming to body temperature they undergo a unimolecular chemical reaction and emit near-infrared light that can pass through a living mouse. [ABSTRACT FROM AUTHOR]

Abstract: Chemiluminescent acridinium ester labels are widely used in clinical diagnostics especially in automated immunochemistry analyzers such as Siemens Healthcare Diagnostics’ ADVIA Centaur® systems. Although, chemiluminescence from acridinium compounds was discovered more than 50 years ago, details regarding the excitation process are still not well understood particularly in relation to acridinium structure and overall light output. Herein, we report an empirical study that correlates the presence of electron-donating methoxy groups at C-2 and/or C-7 in the acridinium ring with increased light output. We further demonstrate that these high light output labels can be combined with hydrophilic functional groups such as hexa(ethylene)glycol to generate unique acridinium esters that are stable and are useful in improving immunoassay sensitivity for both competitive and sandwich automated immunoassays. [ABSTRACT FROM AUTHOR]

The increasing resistance of bacteria to antibiotics is a serious problem, caused in part by excessive and improper use of these drugs. One alternative to traditional antibiotic therapy is photodynamic antimicrobial chemotherapy (PACT) which is based on the use of a photosensitizer (PS), activated by illumination with visible light. The poor penetration of visible light through the skin limits the application of PACT to the treatment of skin infections or the use of invasive procedures. To overcome this problem we report the exploitation of light emitted as a result of the chemiluminescent reaction of luminol to excite the PS and we call this process chemiluminescent photodynamic antimicrobial therapy (CPAT). We studied the effect of free and liposome-encapsulated PS (methylene blue or toluidine blue) on bacteria under excitation by either white external light or chemiluminescence emitted by free or liposome-enclosed luminol. PACT showed slightly better performance that CPAT for free and encapsulated PS for both types of bacteria. CPAT resulted in a three log suppression of Staphylococcus aureus and two log suppression of Escherichia coli growth. The use of CPAT may prove to be a novel and more effective form of antimicrobial therapy, particularly for internal infections not easily accessible to traditional PACT. [ABSTRACT FROM AUTHOR]

Abstract: Background: Screening and diagnosis of Rubella virus infection rely on testing for specific IgG and IgM. Immunoassays may yield different IgG results especially at low values, with difficulties in the evaluation of protective immunity. IgM levels decrease until negative a few weeks or months after acute infection, but individual and assay-related variability is common. Objectives: To evaluate the performance characteristics of the automated immunoassay for Rubella IgG and IgM on the Abbott ARCHITECT. Study design: Twelve laboratories from 7 different Italian regions assayed 6268 routine specimens, comparing qualitative results for IgG and IgM and quantitative for IgG with other widespread immunoassays. Prevalence data for IgG were disaggregated by patients’ group and by age in order to evaluate vaccination coverage. Results: Qualitative concordance for IgG was 97.3% vs. Abbott AxSYM, 95.0% vs. DiaSorin Liaison and 97.7% vs. Behring Enzygnost; ARCHITECT was more sensitive than Liaison and equivalent to the other assays, with a good correlation of IU/mL values with AxSYM (r =0.89). IgG prevalence was 87.1% among pregnant women, indicating a sub-optimal vaccine coverage. IgM reactivity was 1%, except in one site due to an outbreak. IgM concordance was 97.5% vs. Abbott AxSYM, 97.9% vs. DiaSorin Liaison and 97.7% vs. Behring Enzygnost; ARCHITECT was more specific than AxSYM. Conclusions: Our study confirms that in Italy Rubella vaccination coverage among pregnant women is insufficient. The new Rubella IgG and IgM assays on the ARCHITECT analyzer showed a good performance in comparison with other commercial methods. The results obtained and the good precision, indicate their suitability for routine testing. [ABSTRACT FROM AUTHOR]

Abstract: A reusable magnetic bead-based electrochemiluminescence (ECL) DNA biosensor for the detection of genetically modified organism (GMO) is proposed. The sensor method consists of immobilization of biotin-probe using streptavidin-coated magnetic beads, hybridization of target DNA with biotin-probe and ruthenium(II) tris-bipyridal (TBR)-probe, detection of target DNA by direct measuring the ECL emission of TBR. The sensor was applied to detect GMO in engineered tobacco samples. Results indicate that the sensitivity of this sensor method was 5nmol/L of CaMV35S DNA. A stable calibration curve with a wide dynamic range was established. The calibration curve was linear from 5nmol/L to 5μmol/L, thus, made quantitative analysis possible. GM tobacco samples and non-GM tobacco samples were clearly discriminated by the sensor method. Results of the study suggest that the reusable DNA biosensor is a feasible tool for daily GMO detection due to its rapidness, simplicity, safety, sensitivity, reliability and low cost. [ABSTRACT FROM AUTHOR]

Background: Detection of enzyme activity or transgene expression offers potential insight into developmental biology, disease progression, and potentially personalized medicine. Historically, the lacZ gene encoding the enzyme b-galactosidase has been the most common reporter gene and many chromogenic and fluorogenic substrates are well established, but limited to histology or in vitro assays. We now present a novel approach for in vivo detection of b-galactosidase using optical imaging to detect light emission following administration of the chemiluminescent 1,2-dioxetane substrate Galacto- Light PlusTM. Methodology and Principal Findings: B-gal activity was visualized in stably transfected human MCF7-lacZ tumors growing in mice. LacZ tumors were identified versus contralateral wild type tumors as controls, based on two- to tenfold greater light emission following direct intra tumoral or intravenous administration of reporter substrate. The 1,2-dioxetane substrate is commercially available as a kit for microplate-based assays for β-gal detection, and we have adapted it for in vivo application. Typically, 100 μl substrate mixture was administered intravenously and light emission was detected from the lacZ tumor immediately with gradual decrease over the next 20 mins. Imaging was also undertaken in transgenic ROSA26 mice following subcutaneous or intravenous injection of substrate mixture. Conclusion and Significance: Light emission was detectable using standard instrumentation designed for more traditional bioluminescent imaging. Use of 1,2-dioxetane substrates to detect enzyme activity offers a new paradigm for non-invasive biochemistry in vivo. [ABSTRACT FROM AUTHOR]

Summary: Conventional oral exploration (visual and palpation examination) constitutes the current gold standard for oral cancer screening, while biopsy and histopathological examination represents the indispensable study for the detection of cases in patients with an identified lesion. Imaging techniques (DPT, CT, and MRI) are frequently used to supplement the clinical evaluation and staging of the primary tumour and regional lymph nodes. There are also a number of techniques that may contribute to the diagnosis of oral cancer: toluidine blue test has been used as a diagnostic aid for the detection of oral cancer over decades. Recently developed light-based detection systems have progressively improved in sensitivity and specificity, but multicentre controlled studies conducted by general dental practitioners must be designed in order to justify their application. The oral brush biopsy appears to overestimate dysplastic lesions and produces a high number of false-positive results. In the near future, immunological and biochemical alterations in the serum (e.g., circulating immune complexes, carcinoembryonic antigen, squamous cell carcinoma associated antigen, inhibitor of apoptosis, cytokeratin fragments, and annexin A1) as well as specific saliva analysis (e.g., cancer related cytokines, metalloproteinases, epithelial tumour markers, DNA promoter hypermethylation, and saliva micro-RNA) may become important tools for the detection of oral cancer. [Copyright &y& Elsevier]

Abstract: Objective: Telomeres are specialised DNA structures present at the ends of linear chromosomes, which shorten with each successive cell division and the length of which represents cellular biological age. The aim of this study was to determine the relationship between abdominal aortic aneurysm (AAA) and white cell telomere length. Methods: Peripheral blood samples were collected from 190 patients with AAA and 183 controls. Genomic DNA was extracted from white cells and telomere lengths determined using a chemiluminescence technique. Results: The mean white cell telomere length was significantly lower in AAA patients compared to controls (median age 66 years in both groups), with a mean difference of 189 base pairs (bp) (95% confidence interval 77bp to 301bp, P =0.005). This relationship between case–control status and mean telomere restriction fragment (TRF) length did not change after adding other risk factors into a multiple regression model. The risk of having AAA doubled in patients with a mean TRF length in the lowest quartile compared to patients with a mean TRF length in the highest quartile (odds ratio 2.30, 95% Confidence Interval 1.28–4.13, P =0.005). Conclusion: Our data show that patients with AAA have shorter leukocyte telomere length compared to controls. This suggests that vascular biological aging may have a role in the pathogenesis of AAA. [Copyright &y& Elsevier]

The effect of the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate ([Emim][EtSO4]) on the copper-catalyzed luminol chemiluminescence (CL) is reported. A drastic light emission enhancement is observed, related to a strong interaction between Cu2+ and the imidazolium ring. In these conditions, the CL reaction was able to produce light efficiently at pH as low as 6.5 (amplification factom Intensity+ILIntensity-IL = 2900). Interesting effects of [Emim][EtSO4] on the enzyme glucose oxidase activity were also evidenced, and advantages were taken from this enhancement to perform sensitive chemiluminescentglucose detection (LOD = 4μM) at pH 8.0. [ABSTRACT FROM AUTHOR]

Abstract: Background: Midnight salivary cortisol (MSC) concentration has been considered as a sensitive marker of overt hypercortisolism. Because no studies on commercially available automated, non-isotopic MSC assays have been reported, we determined and compared the diagnostic performance of an automated electrochemiluminescent immunoassay (ECLIA, Elecsys E170) and an in-house radioimmunoassay (RIA) for MSC measurement. Methods: The study involved 126 consecutive patients referred for evaluation because of symptoms of Cushing''s syndrome, obesity, or the presence of incidentally discovered adrenal adenoma. Using detailed clinical, hormonal and radiological evaluation overt endogenous hypercortisolism was confirmed in 9 patients and was excluded in 117 patients. Results: ROC analysis indicated that the best performance of MSC was obtained at cutoff value of 0.35µg/dl using ECLIA (sensitivity, 100%; specificity, 88%) and 0.29µg/dl (sensitivity, 100%; specificity, 71%) using RIA. When the findings were compared to those obtained from low dose dexamethasone test, both ECLIA and RIA of MSC showed a better diagnostic performance. Conclusion: MSC measurement is useful for the diagnosis of overt hypercortisolism but the cutoff value is highly dependent on the method used. We recommend the use of automated ECLIA for MSC assay, and we propose further studies on other automated immunoassay analyzers potentially suitable for MSC measurements. [Copyright &y& Elsevier]

Objectives: This study aims to assess the usefulness of serum holotranscobalamin (holoTC), the fraction of vitamin B12 that is available for tissue uptake, compared with total vitamin B12 in patients investigated for vitamin B12 disorders. Methods: Serum samples were randomly selected from 76 patients (48 females, 28 males; age range 12-69 years) referred to the Clinical Biochemistry Laboratory, Royal Hospital for the assessment of vitamin B12 status. For each patient, serum total vitamin B12 level was determined by chemiluminescent microparticle immunoassay on Architect 2000 analyzer and holoTC (active vitamin B12) level was determined by microparticle enzyme immunoassay on Axsym analyzer (both from Abbott, USA). Results: Comparison of the data was conducted to reflect the mean, standard deviation (SD) and correlation coefficient between the two groups. The mean (SD) for serum holoTC and total vitamin B12 were 46.5(32.2) pmol/L and 316.3(165.6) pmol/L respectively. There was a significant correlation between holoTC and total vitamin B12 (r= 0.765, P< 0.001) and the regression equation was expressed as; y = a + bx (i.e: holoTC = 1.5 + 0.14 total vitamin B12). Also, the results were assessed for any misclassification when comparing holoTC and the total vitamin B12 in terms of whether each or both values agree or disagree for classifying the patients as having normal or abnormal (low or high) results, based on the cut-off thresholds of the kit's quoted reference range for holo TC o f 9 - 1 2 3 pmol/L and for total vitamin B12 of 140-600 pmol/L. Accordingly, in 69 (90.8%) samples, there was a parallel agreement/ classification of results, both being normal or abnormal. In 61 (80.4%) patients, both results were normal, whereas in 4 (5.2%) patients, both results were high, and in 4 (5.2%) patients both results were low. However, in 7 (9.8%) cases, there was disagreement/ misclassification of results; 6 (7.8%) patients, holoTC was normal while total vitamin B12 was low, and in 1 (1.4%) patient, holoTC was normal while total vitamin B12 was high. Conclusion: It can be recommended that holoTC and total vitamin B12, alone and in combination, have almost equal diagnostic efficiency in screening/diagnosing vitamin B12 deficiency for the majority of patients. In very few patients, holoTC appeared to be a better reflector of vitamin B12 status. Further comparison studies based on a gold standard method for classifying vitamin B12 status are worth considering. [ABSTRACT FROM AUTHOR]

Measurements of superoxide (O2-) reaction kinetics were made during a transect with the research icebreaker Polarstern (ANT24-3) in the Antarctic through the Drake Passage in austral autumn 2008. Our sampling strategy was designed to investigate the sinks of superoxide in Polar waters; principally through reactions with dissolved organic matter (DOM) or metals (copper and iron). We modified an existing chemiluminescence flow injection system using methyl Cypridina luciferin analog (MCLA) for the detection of O2- and added O2- using KO2 as the source. Our results indicats that O2- in ambient seawater had a half-life ranging from 9.3 to 194 s. DTPA additions to seawater, to remove the effects of reactions with metals, revealed O2- decay rates consistent with a second order reaction, indicating that the dismutation reaction dominated and that reactions with DOM were not significant Titrations of seawater by the addition of nanomolar amounts of iron or copper revealed the importance of organic chelation of Fe and/or Cu in controlling the reactivity with O2-. Throughout the water column reactions with Cu appeared to be the major sink for superoxide in the Southern Ocean. This new strategy suggests an alternative approach for speciation measurements of Fe and Cu in seawater. [ABSTRACT FROM AUTHOR]

The best way to help improve survival rates of oral cancers is early detection and treatment. Almost 80% of patients with these cancers would have a 5-year survival rate if their disease had been found early. Many factors, such as long-term exposure to certain carcinogens, may heighten the risk. It is paramount that a dental clinician be cognizant of the sometimes subtle and overlooked signs and performs appropriate follow-up care. This article discusses common presentations, clinical aids, treatment, and management, as well as provides a detailed clinical evaluation form. Testing techniques such as chemiluminescent examinations and use of the VELscope can help. Ultimately, the dental practitioner bears responsibility for improving survival rates. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus (SARS-CoV) is the etiological agent of a newly emerged disease SARS. The SARS-CoV nucleocapsid (N) protein is one of the most abundant structural proteins and serves as a diagnostic marker for accurate and sensitive detection of the virus. Using a SELEX (systematic evolution of ligand by exponential enrichment) procedure and recombinant N protein, we selected a high-affinity RNA aptamer capable of binding to N protein with a dissociation constant of 1.65 nM. Electrophoretic mobility shift assays and RNA competition experiments showed that the selected aptamer recognized selectively the C-terminal region of N protein with high specificity. Using a chemiluminescence immunosorbent assay and a nanoarray aptamer chip with the selected aptamer as an antigen-capturing agent, we could sensitively detect N protein at a concentration as low as 2 pg/ml. These aptamer–antibody hybrid immunoassays may be useful for rapid, sensitive detection of SARS-CoV N protein. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate that solution processed thin-film organic photodiodes (OPDs) can be used as compact and sensitive integrated detectors for antioxidant capacity screening. The OPDs were fabricated with blends of regioregular poly(3-hexylthiophene) (P3HT) and (6,6)-phenyl C61 butyric-acid methyl-ester (PCBM). The devices had a broadband photoresponse from 350nm to 650nm with a peak responsivity of 0.25 A/W at 550nm and a dark current density of 0.59μA/cm2 under 10mV bias for a device area of 1mm2. The signal rise and fall times of the detectors were 0.51μs and 0.66μs, respectively. The detectors were applied to an on-chip peroxyoxalate chemiluminescence (PO-CL) assay for antioxidant capacity determination. Antioxidant standards were injected into a stream of PO-CL reagents, resulting in a CL emission decrease that correlated with the antioxidant capacity. For the encountered CL signals the OPDs provided a comparable response to photomultiplier tubes (PMTs) commonly used in analytical applications. Antioxidant capacity screening results showed excellent consistency between the two detection methods. The compact and portable detection system is suited not only to low-cost in-the-field antioxidant capacity screening, but could have wider applications for chemiluminescence based diagnostic tests at the point-of-care. [Copyright &y& Elsevier]

Background: When the skin is exposed to solar irradiation, UVA photons interact with skin tissues and induce excessive reactive oxygen species, resulting in oxidative stress. We have shown in a previous study that in vivo chemiluminescence's measurement can be used to evaluate the overall level of UVA-induced oxidative stress in human skin. However, the origin of the observed chemiluminescence signals remains unclear. Methods: UVA-induced chemiluminescence measurements were conducted: (a) in vitro on collagen solutions and solid collagen sheet preparations, (b) ex vivo on human and mouse skin biopsies, and (c) in vivo on human skin of various constitutive pigmentation levels. Fluorescence was measured on collagen in vitro as well as on skin for the in vivo experiments. Results: We found in the in vitro experiments that UVA-induced chemiluminescence increases with the presence of collagen cross-links. When dermal sides were exposed to UVA irradiation, both mouse and human skin biopsies demonstrated significantly higher chemiluminescence levels than when epidermal sides were exposed to UVA. The amount of collagen cross-links decreases slightly following UVA exposure, as shown both by in vivo fluorescence and by UVA-induced chemiluminescence. Finally, there was less measurable UVA-induced chemiluminescence in dark skin compared with light pigmented skin in vivo. Conclusions: The dermis is very sensitive to UVA photons. Dermal cross-links are potential UVA sensitizers. The oxidative stress induced by UVA and measured by chemiluminescence may largely be attributed to the breakdown of dermal collagen cross-links. [ABSTRACT FROM AUTHOR]

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In this study, we explored the effects of soy isoflavone extracts on the growth of estrogen-dependent human breast cancer (MCF-7) tumors implanted in ovariectomized athymic mice. The àvariectomized athymic mice were implanted with MCF-7 cells. They were fed with low, moderate and high doses of soy isoflavone extracts, at dietary concentrations of 6.25, 12.5 and 25 g/kg, respectively. The expression of ki-67 was detected by immunohistochemistry. The pS2 expression in tumors was analyzed by real-time PCR. Estrogen level in the serum was measured by chemiluminescence enzyme immunoassay. Compared with the control group, dietary soy isoflavone extracts had a significant stimulatory effect on MCF-7 tumor growth in mice (P < 0.05). The ki-67 and pS2 mRNA expressions in tumors were significantly increased by 6.25 and 12.5 g/kg dose of soy isoflavone extracts (P< 0.05). And, estrogen level in serum of 6.25 and 12.5 g/kg dose groups was higher than that of control group (P> 0.05). In conclusion, in the tested dietary concentration range soy isoflavone extracts had a stimulatory effect on tumor growth. 6.25 and 12.5 g/kg doses of soy isoflavone extracts can increase the cell proliferation in tumors and induce estrogen-responsive pS2 expression. [ABSTRACT FROM AUTHOR]

Abstract: Metabolic syndrome (MetS) denotes a clustering of risk factors that may affect nitric oxide (NO) bioavailability and predispose to cardiovascular diseases, which are delayed by exercise training. However, no previous study has examined how MetS affects markers of NO formation, and whether exercise training increases NO formation in MetS patients. Here, we tested these two hypotheses. We studied 48 sedentary individuals: 20 healthy controls and 28 MetS patients. Eighteen MetS patients were subjected to a 3-month exercise training (E+group), while the remaining 10 MetS patients remained sedentary (E−group). The plasma concentrations of nitrite, cGMP, and ADMA (asymmetrical dimethylarginine; an endogenous nitric oxide synthase inhibitor), and the whole blood nitrite concentrations were determined at baseline and after exercise training using an ozone-based chemiluminescence assay, and commercial enzyme immunoassays. Thiobarbituric acid reactive species (TBA-RS) were measured in the plasma to assess oxidative stress using a fluorometric method. We found that, compared with healthy subjects, patients with MetS have lower concentrations of markers of NO formation, including whole blood nitrite, plasma nitrite, and plasma cGMP, and increased oxidative stress (all P <0.05). Exercise training increased the concentrations of whole blood nitrite and cGMP, and decreased both oxidative stress and the circulating concentrations of ADMA (both P <0.05). These findings show clinical evidence for lower endogenous NO formation in patients with MetS, and for improvements in NO formation associated with exercise training in MetS patients. [Copyright &y& Elsevier]

An in-situ measurement system for the determination of nitrous acid (HONO) was developed and used at an indoor residential environment. The system uses a diffusion scrubber to sample gaseous HONO and the peroxynitrite-induced luminol chemiluminescent method to quantify the amount of HONO. In this system, the detection limit of HONO, estimated as three times the noise level of the scrubbing solution blank, was 120pptv for a 2-min integrated sample. Indoor HONO and NO x concentrations were determined for 7 days in the living room of an apartment with a gas range for cooking in the kitchen. Close examination of the relationships among HONO, NO, and NO2 concentrations during both the background and combustion periods confirm that the observed HONO was formed not only by direct emission from gas combustion, but also from heterogeneous reactions of NO2 with H2O on indoor surfaces. The average ratio of HONO to NO2 over the study period was 0.12±0.05. The HONO/NO2 concentration ratio was 0.04–0.08 during the combustion period, whereas it was 0.10–0.25 after combustion had stopped. This suggests that HONO was generated through different production processes, both during combustion and after the completion of combustion. The controlled combustion experiments indicate that the burning rate is an important factor to determine the peak HONO concentration. In darkness, HONO had a nearly constant removal rate for all of the combustion experiments, whereas the removal rates of NO and NO2 depended on the burning rates of the gas range. Combustion experiments conducted at the fixed burning rate setting show also that ventilation decreased HONO concentration. This indicates that the airflow rate of the range hood fan is an important factor to control the concentration of indoor air pollutants. [Copyright &y& Elsevier]

Abstract: Since nearly 90% of all developmental and marketed drugs contain at least one nitrogen atom, the implementation of chemiluminescent nitrogen detection (CLND) in pharmaceutical analysis is intriguing due to its equimolar response for nitrogen. Although the documented accuracy of CLND when using a surrogate nitrogen-containing standard may be inadequate for purity and potency determinations, it is acceptable for the quantitation of low-level impurities. A comparison of the quantitative results obtained using both CLND and UV detection for a developmental drug and its related impurities is presented. The results indicated that the impurities can be accurately quantified using a surrogate standard, based on the equimolar response principle of CLND, when the concentrations of the surrogate standard and the component of interest are similar. When the impurities are present at much lower levels than the surrogate standard however, the common practice of direct conversion of area percent to weight percent can result in significant errors using CLND, due to the limited linear dynamic range for CLND. To increase quantitation accuracy, the authors propose that a secondary dilution of the surrogate reference standard solution should be used for the quantitation of low-level impurities. The practical application of this approach for impurity quantitation or as a means to determine impurity relative response factors for use with a traditional UV based method is discussed. [Copyright &y& Elsevier]

A simple, rapid, injection chemiluminescence method is described for the determination of prulifloxacin, a commonly used antibiotic. A strong chemiluminescence signal was detected when a mixture of the analyte and tris-(4,7-diphenyl-1,10-phenanthrolinedisulfonic acid)ruthenium(II) was injected into cerium(IV) sulfate. The chemiluminescence signal is proportional to the concentration of prulifloxacin in the range 4.0 × 10-8-9.0 × 10-6 mol L-1. The detection limit is 1.0 × 10-8 mol L-1, and the relative standard deviation is 2.2% (n = 11) for the determination of 8.0 × 10-7 mol L-1 prulifloxacin. The proposed method was successfully applied to the determination of prulifloxacin in pharmaceutical preparations in capsules, spiked serum, and urine samples. [ABSTRACT FROM AUTHOR]

Summary: Conventional visual examination and palpation remains the gold-standard for the identification of oral mucosal lesions. The purpose of this study was to investigate the adjunctive value of a chemiluminescent light source (ViziLite®, Zila Pharmaceuticals, Phoenix, Arizona) and application of pharmaceutical grade toluidine blue (TBlue630™, Zila Pharmaceuticals, Phoenix, Arizona) to further assess lesions identified during the conventional oral soft tissue examination. Lesions deemed clinically suspicious by visual examination under incandescent light were further assessed under chemiluminescence and then application of toluidine blue stain. Differences between the conventional visual examination and chemiluminescent examination were noted on four characteristics which may aid in lesion identification. Tissue retention of toluidine blue stain was documented. Each suspicious lesion was biopsied and diagnosed based upon routine histopathology. Both adjunctive exams were evaluated by comparing the histologic diagnosis. The additive value of toluidine blue stain retention was assessed in lesions diagnosed as “serious pathology” defined as severe dysplasia, carcinoma in situ and squamous cell carcinoma. Ninety-seven clinically suspicious lesions in 84 patients were identified. The chemiluminescent exam improved the brightness and/or sharpness of margin in 61.8% of identified lesions. Biopsied lesions with toluidine blue stain retention reduced the false positive rate by 55.26% while maintaining a 100% negative predictive value (NPV). Chemiluminescence was shown to increase the brightness and margins of mucosal lesions in a majority of cases and therefore may assist in identification of mucosal lesions not considered under traditional visual examination. Toluidine blue stain retention was associated with a large reduction in biopsies showing benign histology (false positive biopsy results), while maintaining a 100% NPV for the presence of severe dysplasia or cancer. Practitioners may consider use of these adjuncts in practice, however the results presented are based upon experienced providers in referral centers for mucosal disease or cancer centers and therefore positive findings may be an indication for referral to experienced providers. [Copyright &y& Elsevier]

Abstract: A simple and convenient end-column chemiluminescence (CL) detection coupled to pressurized capillary electrochromatography (pCEC) was described. Luminol and N-(4-aminobutyl)-N-ethylisoluminol (ABEI) were adopted as mode compounds to evaluate the feasibility of end-column reactor. Detailed analysis of ABEI revealed that the high sensitivity could be obtained with the reactor. Furthermore, determination of norepinephrine (NE) and epinephrine (EP), which were labeled with ABEI, was accomplished by using the end-column pCEC–CL detection based on ABEI–potassium ferricyanide–alkaline medium CL reaction system. Under the optimum conditions, the detection limit (S/N=3) of NE and EP was 0.08μM and 0.06μM, respectively. The proposed method has also been successfully applied to the analysis of adrenaline hydrochloride injection sample. [Copyright &y& Elsevier]

ObjectiveReactive oxygen species (ROS), mainly produced by polymorphonuclear neutrophils (PMN), are a significant part of host defense in pathologic states. We attempted to relate numbers of PMN and ROS generated within PMN to develop an alternative photochemical approach for evaluation of the potential of these cells to resist the development of inflammatory pathology. Background DataLack of sensitivity to light has been reported in healthy cells, while sensitivity to light characterizes cell pathology. MethodsHuman leukocytes from 34 donors were isolated and irradiated with a non-laser blue light (2 and 5 mWcm2for 2 minutes), and a luminol-dependent chemiluminescence assay that reflects intracellular production of ROS was applied thereafter. The levels of basal chemiluminescence (BCL) were related to respective numbers of PMN. ResultsA light-insensitive cluster was discovered within the total sample and was considered to be a discrete nonpathological group. Following elimination of this group, the rest of the sample was divided into three well-defined light-sensitive groups, which were attributed to various pathological states, and differed in PMN numbers and BCL counts. Within these groups the two traits were interrelated, and each PMN range was associated with a respective level of intracellular ROS. ConclusionsLeukocyte responsiveness to light can be used for discrimination between pathological and nonpathological states and prognostic evaluation of pathological development. Patients exhibiting similar clinical symptoms could be divided into separate groups with potentially different outcomes. A novel definition of nonpathological states as well as the mechanism underlying the bell-shaped curve that delineates the relationship between PMN number and intracellular ROS is suggested in pathological states. [ABSTRACT FROM AUTHOR]

We describe a new laboratory-based method for in situ detection of nitrous acid (HONO) using a combination of thermal dissociation (TD) and chemiluminescent (CL) detection of nitric oxide. A prototype was built using a commercial NO sensor. Laboratory tests for possible chemical interferences show that measurements are affected in predictable ways by , peroxy nitrates, alkyl nitrates, , and . [Copyright &y& Elsevier]

Abstract: We report herein the development of an optical fiber based chemiluminescent immunosensor for detection of the native autoimmune response to GIPC-1, a PDZ containing protein involved in regulation of G-protein signaling. The recombinant protein GIPC-1 was expressed in bacteria, purified, refolded and conjugated to the tip of an optical fiber. A human monoclonal 27.B1 IgM isolated from a breast cancer patient, which targets the GIPC-1 protein, was used for calibration of the immunosensor and was detected down to a concentration of 30pg/ml. We determined that the fiber-optic immunosensor had a detection limit 50 times lower than chemiluminescent ELISA, and approximately 500 times lower than colorimetric ELISA. In addition, sera from 11 ovarian cancer patients, 22 breast cancer patients and asymptomatic controls were tested for the presence of IgM anti-GIPC-1 autoantibodies in their serum using the two methods. The immunosensor assay detected 54% and 77% GIPC-1 positive sera within ovarian and breast cancer patients, respectively, as compared to chemiluminescent ELISA, which only detected 18% and 27%, respectively. We envision that this immunosensor may serve as a diagnostic tool for screening women for ovarian and breast cancer at an early stage, thus increasing their chance of survival. [Copyright &y& Elsevier]

Abstract: A chemiluminescence immunoassay for the detection of four heart marker proteins: myoglobin, creatine kinase mb [CKmb], troponin I [TnI], and fatty acid-binding protein [FABP], was designed. The immunoassay was based on enzyme-linked immunosorbent assay [ELISA] and antibodies immobilized in glass capillaries pre-treated with 3-aminopropyltriethoxysilane. The protein bound to the antibody was detected by using an anti-protein-horseradish peroxidase [HRP] conjugate. The reaction of the HRP with luminal and hydrogen peroxide-based substrate generated the chemiluminescence and a photodiode detector was used to measure the light intensity. The same assay protocol was used to detect all four proteins. Ultrasound waves were used to improve the silanization of glass and the antibody immobilization process. The optimization of the duration and intensity of the ultrasound was performed for the myoglobin assay. Ultrasound improved the silanization procedure and the capillaries gave an approximately 2.5 times greater ELISA response. Ultrasound also improved the sensitivity by approximately 100% when monoclonal antibody was immobilized on a glass capillary. Calibration curves corresponding to analyte concentrations ranging from 2.4 to 2400ng/ml in plasma samples were recorded. The detection limits were in the region of 1.2 myoglobin, 0.6 CKmb, 5.6 TnI, and 4ng/ml FABP in plasma with a coefficient of variation of 3–9.9%. [Copyright &y& Elsevier]

Chronic renal failure (CRF) patients suffer from a chronic inflammation. They are at increased risk of cardiovascular disease. In order to investigate this inflammatory process and cardiovascular risk factors associated with haemodialysis (HD) and peritoneal dialysis (PD), we compared serum/plasma pro-inflammatory cytokines, C-reactive protein (CRP), and cardiac troponin T (cTnT) of 146 CRF patients treated or not treated with PD or HD. Serum cytokines and CRP as well as plasma cTnT were measured by enzyme-linked immunosorbent assay, chemiluminescence immunoassay, and electrochemiluminescence immunoassay, respectively. Results indicated that serum interleukin (IL)-18 concentrations were significantly higher in PD and low creatinine clearance pre-dialysis CRF (LCC) patients than HD patients (both p < 0.05). IL-6 and tumour necrosis factor (TNF)-α concentrations were significantly higher in PD patients than LCC patients (both p < 0.01). Serum hsCRP and plasma cTnT in HD were significantly higher than LCC (both p < 0.01). The elevation of pro-inflammatory cytokines should play an important role in the chronic inflammation and increased cardiovascular risk of CRF patients on dialysis. We are evaluating further the diagnostic and prognostic applications of pro-inflammatory cytokines and biochemical inflammatory markers for these patients. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Table beet (Beta vulgaris var. rubra) contains important bioactive agents (betaine and polyphenols), which have a wide range of physiologic effects. Because nutritive antioxidants may reduce the occurrence of complications and postoperative mortality, dietary intake of polyphenols and vitamins before surgery may greatly contribute to the survival of patients. Our aim was to determine the liver-protecting properties of bioactive substances of table beet in a model of ischemia-reperfusion injury of the rat. Methods: Wistar rats were divided into two groups: non-treated (n = 24) and fed with table beet (n = 8). For 10 days the second group was treated with lyophilized table beet (2 g/kg body weight daily) mixed into the rat chow. Hepatic ischemia was maintained for 45 min, followed by 15 min of reperfusion. Ischemia-reperfusion was carried out on animals from both groups. Chemiluminescent intensity, H-donating ability, reducing power, free SH group concentration, Randox-total antioxidant status, glutathione peroxidase, and superoxide dismutase activities were determined by luminometry and spectrophotometry. Fatty acid (Shimadzu GC) and metal ion (inductively coupled plasma optical emission spectrometry) concentrations were observed in the liver. Results: As a result of feeding, global parameters (H-donating ability, reducing power, free SH group concentration) and enzymatic antioxidants (glutathione peroxidase and superoxide dismutase) of the liver were found to increase significantly, which indicated that the treatment had a positive effect on its redox state. The increase found in zinc and copper content may protect the hepatocytes against oxidative stress because these elements are required for the function of superoxide dismutase enzymes. In the table beet group the concentration of short-chain fatty acids decreased, whereas that of long-chain fatty acids increased. The changes in metal element and fatty acid concentrations confirmed that these elements have an essential function in cellular pathways. Conclusion: It may be stated that a natural antioxidant-rich diet has a positive effect on redox homeostasis during hepatic ischemia-reperfusion. [Copyright &y& Elsevier]

Abstract: The present paper deals with the chemiluminescent determination of the herbicide Karbutilate on the basis of its previous photodegradation by using a low-pressure Hg lamp as UV source in a continuous-flow Multicommutation assembly (a solenoid valves set). The pesticide solution was segmented by a solenoid valve and sequentially alternated with segments of the 0.001moll−1 of NaOH solution, the suitable media for the formation of photo-fragments; then it passes through the photo-reactor and was lead to the flow-cell after being divided in small segments which were sequentially alternated with the oxidizing system; 2×10−5 moll−1 of potassium permanganate in 0.2% pyrophosphoric acid. The studied calibration range, from 0.1μgl−1 to 65mgl−1, resulted in a linear behaviour over the range 20μgl−1–20mgl−1 and fitting the linear equation: I =(1180±30)C +(15±5) with the correlation coefficient 0.9998. The limit of detection was 10μgl−1 and the sample throughput 17h−1. After testing the influence of a large series of potential interfering species, the method was applied to water and human urine samples. [Copyright &y& Elsevier]

The purpose of the present review is to sketch out the scope of luminol chemiluminescence in human urine analysis. Practical considerations and experimental requirements are indicated. The literature revised covers the papers of analytical interest that have appeared in approximately the last six years. [ABSTRACT FROM AUTHOR]