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Effective treatment of ovarian cancer depends upon the early detection of the malignancy. Here, we report on the development of a new nanostructured immunosensor for early detection of cancer antigen 125 (CA-125). A gold electrode was modified with mercaptopropionic acid (MPA), and then consecutively conjugated with silica coated gold nanoparticles (AuNP@SiO2), CdSe quantum dots (QDs) and anti-CA-125 monoclonal antibody (mAb). The engineered MPA|AuNP@SiO2|QD|mAb immunosensor was characterised using transmission electron microscopy (TEM), atomic force microscopy (AFM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Successive conjugation of AuNP@SiO2, CdSe QD and anti-CA-125 mAb onto the gold electrode resulted in sensitive detection of CA-125 with a limit of detection (LOD) of 0.0016 U mL(-1) and a linear detection range (LDR) of 0-0.1 U mL(-1). Based on the high sensitivity and specificity of the immunosensor, we propose this highly stable and reproducible biosensor for the early detection of CA-125.

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Introduction: A number of assays have so far been exploited for detection of cancer biomarkers in various malignancies. However, the expression of cancer biomarker(s) appears to be extremely low, therefore accurate detection demands sensitive optical imaging probes. While optical detection using conventional fluorophores often fail due to photobleaching problems, quantum dots (QDs) offer stable optical imaging in vitro and in vivo. Methods: In this review, we briefly overview the impacts of QDs in biology and its applications in bioimaging of malignancies. We will also delineate the existing obstacles for early detection of cancer and the intensifying use of QDs in advancement of diagnostic devices. Results: Of the QDs, unlike the II-VI type QDs (e.g., cadmium (Cd), selenium (Se) or tellurium (Te)) that possess inherent cytotoxicity, the I-III-VI 2 type QDs (e.g., AgInS2, CuInS2, ZnS-AgInS2) appear to be less toxic bioimaging agents with better control of band-gap energies. As highly-sensitive bioimaging probes, advanced hybrid QDs (e.g., QD-QD, fluorochrome-QD conjugates used for sensing through fluorescence resonance energy transfer (FRET), quenching, and barcoding techniques) have also been harnessed for the detection of biomarkers and the monitoring of delivery of drugs/genes to the target sites. Antibody-QD (Ab-QD) and aptamer- QD (Ap-QD) bioconjugates, once target the relevant biomarker, can provide highly stable photoluminescence (PL) at the target sites. In addition to their potential as nanobiosensors, the bioconjugates of QDs with homing devices have successfully been used for the development of smart nanosystems (NSs) providing targeted bioimaging and photodynamic therapy (PDT). Conclusion: Having possessed great deal of photonic characteristics, QDs can be used for development of seamless multifunctional nanomedicines, theranostics and nanobiosensors.

Our objective was to examine the effect of orange juice and hesperetin on serum total antioxidant capacity (TAC), lipid peroxidation (MDA), uric acid and hepatic xanthine oxidase (XO) and xanthine dehydrogenase (XDH) activity in hyperuricemic rats. Experimentally hyperuricemia in rats was induced by intraperitoneal injection of potassium oxonate (250 mg/kg). Orange juice (5 ml/kg) and hesperetin (5 mg/kg) was given by oral gavage to rats for 2 weeks and biochemical data was measured. Data showed that orange juice supplementation increased serum TAC and decreased MDA concentration (p≤0.05). Orange juice also inhibited hepatic XO and XDH activity and decreased serum uric acid levels. Hesperetin, which is the main flavanone constituent in orange juice, also exhibited antioxidative and antihyperuricemic properties, but its effect was weaker than that of orange juice. Although the hypouricemic effect of allopurinol (5 mg/kg), as a positive control, was much higher than that of orange juice and hesperetin, it could not significantly change biomarkers of oxidative stress. These features of orange juice and hesperetin make them an attractive candidate for the prophylactic treatment of hyperuricaemia, particularly if these compounds are to be taken on a long-term basis.

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Purpose:To evaluate the effects of onion juice on sodium-selenite induced cataract formation.Materials and Methods:Thirty-two 10-day-old Wistar-albino rat pups were divided into four equal groups. Group 1 received only subcutaneous saline injection. In Group 2, sodium-selenite (30 nmol/g body weight) was injected subcutaneously. In Group 3, subcutaneous sodium-selenite was injected and one drop 50% diluted fresh juice of crude onion was instilled every 8 h into the right eye for 14 days; the left eye received no treatment. Group 4 rats were similar to those of Group 3, the only difference being that of undiluted fresh juice of crude onion. The development of cataract was assessed. Rat lenses were analyzed for total antioxidant (TA) level, and for activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD).Results:Both eyes of all rats in Group 1 did not exhibit cataract formation. In Group 2, all rats developed Grade 3 cataract in the lenses of both eyes. The difference in exhibited cataract in the lens of the right eyes in all rats between Group 2 and any eyes of groups 3 or 4 were significant (P = 0.001). The mean TA level and mean activities of SOD and GPX in Group 2 rat lenses were significantly lower than the values in lenses of all rats in Group 1 (P = 0.001, 0.003, 0.001), and in the lenses of the right eyes of rats in Groups 3 and 4 (P = 0.001, 0.020, 0.001).Conclusion:Instillation of onion juice into the rat eyes can effectively prevent selenite-induced cataract formation. This effect was associated with increased TA level, SOD and GPX activities in the lens.