Sol-gel synthesized plasmonic nanoparticles and their integration into dye sensitized solar cells

In the present study, we synthesized silver nanoparticles in titanosilicate matrix through low cost non-hydrolytic sol-gel method using titanium isopropoxide (TIP), tetraethylorthosilicate (TEOS, (Si(OC2H5)4) and ethanol (C2H5OH) as solvents. These were investigated for the plasmonic effect of nanoparticles in dye sensitized solar cells (DSSC). The fabricated dye-sensitized solar cells with Ag: SiO2-TiO2 films coated in fluorine doped tin oxide (FTO) glass plate with dye of amaranthus red shows an improved output voltage. The samples were optically and structurally well studied by absorption spectroscopy, Fourier transform infrared spectroscopy(FTIR), X-Ray diffraction (XRD) and transmission electron microscopy(TEM). The XRD studies confirmed the crystalline nature of TiO2 and Ag.publishe

Insights into the Recent Advances in Nanomaterial Based Electrochemical Sensors for Pesticides in Food

Food safety is one of the rising concerns challenging all over the world and the analysis and determination of food contaminants to ensure the quality of food is highly inevitable. Electroanalytical sensors are a versatile tool for the accurate monitoring of food samples from the pollutants. Pesticides are one of the major sources of food pollutants and their impacts on human health is also very dangerous. This will trigger the researchers to develop more and more sensitive devices to monitor the level of various pesticides in various food samples, especially in agricultural products. Electrochemical sensors fabricated using nanocomposites offers more sensitive electrochemical response in the detection of these pesticides than traditional unmodified electrodes. This prompted us to write a mini review on the electrochemical sensors for pesticides in food using nanomaterials as modifiers from some of the previous reports. This review will motivate the experts working in this area to develop highly efficient sensing devices for pesticides, beneficial to the society as well

The PICTURE study: diagnostic accuracy of multiparametric MRI in men requiring a repeat prostate biopsy.

BACKGROUND: Transrectal prostate biopsy has limited diagnostic accuracy. Prostate Imaging Compared to Transperineal Ultrasound-guided biopsy for significant prostate cancer Risk Evaluation (PICTURE) was a paired-cohort confirmatory study designed to assess diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) in men requiring a repeat biopsy. METHODS: All underwent 3 T mpMRI and transperineal template prostate mapping biopsies (TTPM biopsies). Multiparametric MRI was reported using Likert scores and radiologists were blinded to initial biopsies. Men were blinded to mpMRI results. Clinically significant prostate cancer was defined as Gleason ⩾4+3 and/or cancer core length ⩾6 mm. RESULTS: Two hundred and forty-nine had both tests with mean (s.d.) age was 62 (7) years, median (IQR) PSA 6.8 ng ml (4.98-9.50), median (IQR) number of previous biopsies 1 (1-2) and mean (s.d.) gland size 37 ml (15.5). On TTPM biopsies, 103 (41%) had clinically significant prostate cancer. Two hundred and fourteen (86%) had a positive prostate mpMRI using Likert score ⩾3; sensitivity was 97.1% (95% confidence interval (CI): 92-99), specificity 21.9% (15.5-29.5), negative predictive value (NPV) 91.4% (76.9-98.1) and positive predictive value (PPV) 46.7% (35.2-47.8). One hundred and twenty-nine (51.8%) had a positive mpMRI using Likert score ⩾4; sensitivity was 80.6% (71.6-87.7), specificity 68.5% (60.3-75.9), NPV 83.3% (75.4-89.5) and PPV 64.3% (55.4-72.6). CONCLUSIONS: In men advised to have a repeat prostate biopsy, prostate mpMRI could be used to safely avoid a repeat biopsy with high sensitivity for clinically significant cancers. However, such a strategy can miss some significant cancers and overdiagnose insignificant cancers depending on the mpMRI score threshold used to define which men should be biopsied

Transperineal Magnetic Resonance Imaging-targeted Biopsy versus Transperineal Template Prostate Mapping Biopsy in the Detection of Localised Radio-recurrent Prostate Cancer

AIMS: Multi-parametric magnetic resonance imaging (mpMRI) may identify radio-recurrent intra-prostatic cancer accurately. We aimed to compare visually directed MRI-targeted biopsies (MRI-TB) to an accurate reference standard - transperineal prostate mapping (TPM) biopsies with 5 mm sampling - in the detection of clinically significant cancer in men with biochemical failure after radiotherapy. MATERIALS AND METHODS: A retrospective registry analysis between 2006 and 2014 identified 77 men who had undergone mpMRI followed by MRI-TB and TPM. Clinical significance was set at two definitions of disease. Definition 1 was Gleason ≥ 4+3 and/or maximum cancer core length ≥ 6 mm. Definition 2 was Gleason ≥ 3+4 and/or maximum cancer core length ≥ 4 mm. RESULTS: Of the 77 patients included, the mean age was 70 years (range 61-82; standard deviation 5.03). The median prostate-specific antigen (PSA) at the time of external beam radiotherapy (EBRT) was 14 ng/ml (interquartile range 7.83-32.50). The most frequent EBRT dose given was 74 Gy over 37 fractions. Eight patients had iodine-seed implant brachytherapy or high dose rate brachytherapy. Neoadjuvant/adjuvant hormonal therapy use was reported in 38. The time from EBRT to biochemical recurrence was a median of 60 months (interquartile range 36.75-85.00). The median PSA at the time of mpMRI was 4.68 ng/ml (interquartile range 2.68-7.60). The median time between mpMRI and biopsy was 2.76 months (interquartile range 1.58-4.34). In total, 2392 TPM and 381 MRI-TB cores were taken with 18% and 50% cancer detection, respectively. Detection rates of definition 1 clinically significant cancer were 52/77 (68%) versus 55/77 (71%) for MRI-TB and TPM, respectively. MRI-TB was more efficient requiring 1 core versus 2.8 cores to detect definition 2 cancer. CONCLUSION: MRI-TB seems to have encouraging detection rates for clinically significant cancer with fewer cores compared with TPM, although TPM had higher detection rates for smaller lower grade lesions

Multiparametric ultrasound versus multiparametric MRI to diagnose prostate cancer (CADMUS): a prospective, multicentre, paired-cohort, confirmatory study

BACKGROUND: Multiparametric MRI of the prostate followed by targeted biopsy is recommended for patients at risk of prostate cancer. However, multiparametric ultrasound is more readily available than multiparametric MRI. Data from paired-cohort validation studies and randomised, controlled trials support the use of multiparametric MRI, whereas the evidence for individual ultrasound methods and multiparametric ultrasound is only derived from case series. We aimed to establish the overall agreement between multiparametric ultrasound and multiparametric MRI to diagnose clinically significant prostate cancer. METHODS: We conducted a prospective, multicentre, paired-cohort, confirmatory study in seven hospitals in the UK. Patients at risk of prostate cancer, aged 18 years or older, with an elevated prostate-specific antigen concentration or abnormal findings on digital rectal examination underwent both multiparametric ultrasound and multiparametric MRI. Multiparametric ultrasound consisted of B-mode, colour Doppler, real-time elastography, and contrast-enhanced ultrasound. Multiparametric MRI included high-resolution T2-weighted images, diffusion-weighted imaging (dedicated high B 1400 s/mm2 or 2000 s/mm2 and apparent diffusion coefficient map), and dynamic contrast-enhanced axial T1-weighted images. Patients with positive findings on multiparametric ultrasound or multiparametric MRI underwent targeted biopsies but were masked to their test results. If both tests yielded positive findings, the order of targeting at biopsy was randomly assigned (1:1) using stratified (according to centre only) block randomisation with randomly varying block sizes. The co-primary endpoints were the proportion of positive lesions on, and agreement between, multiparametric MRI and multiparametric ultrasound in identifying suspicious lesions (Likert score of ≥3), and detection of clinically significant cancer (defined as a Gleason score of ≥4 + 3 in any area or a maximum cancer core length of ≥6 mm of any grade [PROMIS definition 1]) in those patients who underwent a biopsy. Adverse events were defined according to Good Clinical Practice and trial regulatory guidelines. The trial is registered on ISRCTN, 38541912, and ClinicalTrials.gov, NCT02712684, with recruitment and follow-up completed. FINDINGS: Between March 15, 2016, and Nov 7, 2019, 370 eligible patients were enrolled; 306 patients completed both multiparametric ultrasound and multiparametric MRI and 257 underwent a prostate biopsy. Multiparametric ultrasound was positive in 272 (89% [95% CI 85-92]) of 306 patients and multiparametric MRI was positive in 238 patients (78% [73-82]; difference 11·1% [95% CI 5·1-17·1]). Positive test agreement was 73·2% (95% CI 67·9-78·1; κ=0·06 [95% CI -0·56 to 0·17]). Any cancer was detected in 133 (52% [95% CI 45·5-58]) of 257 patients, with 83 (32% [26-38]) of 257 being clinically significant by PROMIS definition 1. Each test alone would result in multiparametric ultrasound detecting PROMIS definition 1 cancer in 66 (26% [95% CI 21-32]) of 257 patients who had biopsies and multiparametric MRI detecting it in 77 (30% [24-36]; difference -4·3% [95% CI -8·3% to -0·3]). Combining both tests detected 83 (32% [95% CI 27-38]) of 257 clinically significant cancers as per PROMIS definition 1; of these 83 cancers, six (7% [95% CI 3-15]) were detected exclusively with multiparametric ultrasound, and 17 (20% [12-31]) were exclusively detected by multiparametric MRI (agreement 91·1% [95% CI 86·9-94·2]; κ=0·78 [95% CI 0·69-0·86]). No serious adverse events were related to trial activity. INTERPRETATION: Multiparametric ultrasound detected 4·3% fewer clinically significant prostate cancers than multiparametric MRI, but it would lead to 11·1% more patients being referred for a biopsy. Multiparametric ultrasound could be an alternative to multiparametric MRI as a first test for patients at risk of prostate cancer, particularly if multiparametric MRI cannot be carried out. Both imaging tests missed clinically significant cancers detected by the other, so the use of both would increase the detection of clinically significant prostate cancers compared with using each test alone. FUNDING: The Jon Moulton Charity Trust, Prostate Cancer UK, and UCLH Charity and Barts Charity

Insights into the Recent Advances in Nanomaterial Based Electrochemical Sensors for Pesticides in Food

Food safety is one of the rising concerns challenging all over the world and the analysis and determination of food contaminants to ensure the quality of food is highly inevitable. Electroanalytical sensors are a versatile tool for the accurate monitoring of food samples from the pollutants. Pesticides are one of the major sources of food pollutants and their impacts on human health is also very dangerous. This will trigger the researchers to develop more and more sensitive devices to monitor the level of various pesticides in various food samples, especially in agricultural products. Electrochemical sensors fabricated using nanocomposites offers more sensitive electrochemical response in the detection of these pesticides than traditional unmodified electrodes. This prompted us to write a mini review on the electrochemical sensors for pesticides in food using nanomaterials as modifiers from some of the previous reports. This review will motivate the experts working in this area to develop highly efficient sensing devices for pesticides, beneficial to the society as well