The frequency of NUDT15 rs116855232 and its impact on mercaptopurine-induced toxicity in Syrian children with acute lymphoblastic leukemia.

Introduction: Polymorphisms in NUDT15 may result in differences in mercaptopurine-induced toxicity. This study aimed to identify the frequency of the NUDT15 (c.415C>T; rs116855232) polymorphism and investigate the effect of this polymorphism on mercaptopurine-induced toxicity in a population of Syrian patients with childhood acute lymphoblastic leukemia (ALL). Methods: This is a retrospective study that included children with ALL reaching at least 6 months of maintenance therapy. The NUDT15 genotyping was determined using standard targeted sequencing of polymerase chain reaction products. The odds ratio (OR) for the association between toxicity and genotype was evaluated. Results: A total of 92 patients were enrolled. The majority of the patients in the study population were low-risk (63.04%), followed by intermediate-risk (25%), and high-risk (11.96%). There were 5 patients (5.4%) with NUDT15 (c.415C>T; rs116855232) CT genotype, and 1 patient (1.08%) with NUDT15 TT genotype, with allele frequencies of C=0.962 and T=0.038. The mercaptopurine median dose intensity was 100%, 54.69%, and 5% for the genotypes CC, CT, and TT, respectively (P=0.009). Early onset leukopenia was significantly associated with the NUDT15 polymorphism (OR: 6.16, 95% CI: 1.11-34.18, P=0.037). There was no association between the NUDT15 genotype and hepatotoxicity. Conclusion: Approximately 6.5% of the study population exhibited reduced NUDT15 activity. The mercaptopurine dose intensity was considerably low in NUDT15 rs116855232 TT genotype compared with CT and CC. The dosage of mercaptopurine should be adjusted according to the NUDT15 genotype in pediatric patients with ALL.

Self-reported preparedness of final year undergraduate dental students and interns in Saudi Arabia: a multi-institutional study.

BACKGROUND: Contemporary undergraduate dental education aims to equip the dental students with clinical competence, empathy, and professionalism to enable them to deliver safe and effective dental care to the communities. The purpose of this study was to assess the self-reported preparedness of final year dental students and interns at three Saudi dental institutions, using the pre-validated Dental Undergraduates Preparedness Assessment Scale (DU-PAS). METHODS: A cross-sectional study design was employed to assess the self-reported preparedness of the participants using the DU-PAS. Following ethics approval, a probability sampling technique was used to recruit undergraduate dental students and interns from three dental institutions in Saudi Arabia. The data was collected online on Google Forms and all participants provided their consent to participate in the study prior to providing their responses to DU-PAS. RESULTS: Responses were received from 397 participants including 171 males and 226 females yielding a response rate of 60.3%. The total mean score of the participants was 81.85 ± 13.11. Although higher scores were reported in males, the interaction between gender and DU-PAS scores were not significant. Interaction between DU-PAS scores and stage of education showed significant effect of the stage of education with interns reporting higher overall scores. The participants reported that they were able to perform most clinical procedures independently. However, low confidence was reported in performing multi-rooted endodontics, fabrication of removable dentures and orthodontic assessment. The participants also expressed their confidence in a wide range of behavioural attributes related to communication, teamworking and professionalism. However, lack of experience was noted in referral for oral cancer, interpreting research, and evaluation of new dental products using an evidence-based approach. CONCLUSION: The study provides useful insights into the self-reported preparedness of undergraduate dental students and interns in three dental institutions. While the overall preparedness of the participants was comparable to their international peers, the findings underscore the need for further enhancements to the teaching and training of undergraduate students particularly in multirooted endodontics, removable prosthodontics and orthodontics.

Application of Aptamer-SERS Nanotags for Unveiling the PD-L1 Immunomarker Progression Correlated to the Cell Metabolic Bioprocess.

In recent years, the expression and progression of programmed cell death ligand 1 (PD-L1) as an immunomarker in the context of a cell metabolic environment has gained significant attention in cancer research. However, intercellular bioprocesses that control the dynamics of PD-L1 have been largely unexplored. This study aimed to explore the cell metabolic states and conditions that govern dynamic variations of PD-L1 within the cell metabolic environment using an aptamer-based surface-enhanced Raman scattering (SERS) approach. The aptamer-SERS technique offers a sensitive, rapid, and powerful analytical tool for targeted and nondestructive detection of an immunomarker with high sensitivity and specificity. By combining aptamer-SERS with cell state profiling, we investigated the modulation in PD-L1 expression under different metabolic states, including glucose deprivation, metabolic coenzyme activity, and altered time/concentration-based cytokine availability. The most intriguing features in our findings include the cell-specific responses, cell differentiation by revealing distinct patterns, and dynamics of PD-L1 in different cell lines. Additionally, the time-dependent variations in PD-L1 expression, coupled with the dose-dependent relationship between glucose concentration and PD-L1 levels, underscore the complex interplay between immune checkpoint regulation and cellular metabolism. Therefore, this work demonstrates the advantages of using highly-sensitive and specific aptamer-SERS nanotags for investigating the immune checkpoint dynamics and related metabolic bioprocess.

Unravelling the dilemma of self-medication in Egypt: a cross-sectional survey on knowledge, attitude, and practice of the general Egyptian population.

BACKGROUND: Self-medication (SM) is a rising public health issue, especially in developing countries. It can be associated with various problems such as the delayed seeking of medical advice, drug interactions, and serious events such as antimicrobial drug resistance. We aimed to evaluate the Egyptian general population's knowledge, attitudes, and practices of SM. METHODS: We employed a cross-sectional design between February 7th and March 8th, 2023 using a self-administered questionnaire available in Arabic. The questionnaire was developed based on previous studies and included four domains: sociodemographic data, knowledge, attitude, and practice of SM. We utilized both online (Google Forms) and paper surveys, utilizing convenience and snowball sampling methods. Data were analyzed using R Statistical Software (v4.1.3; R Core Team 2022). RESULTS: 1630 Egyptian individuals (838 females and 792 males) from the seven provinces were enrolled, with a median age of 25 years (IQR: 22-40). Around 55.97% and 48.28% of the participants had good knowledge and favorable attitudes regarding SM respectively, while 62.8% had practiced SM in the previous three months. The most frequently used medications were painkillers (60.74%) followed by antibiotics (32.13%) and antipyretics (28.61%). The pharmacist's recommendation was the source of SM for 53.61% while 31.53% used old medications at home. Most participants (59.08%) practiced SM because they thought they had simple or minor symptoms. The multivariate regression analysis revealed that females had significantly higher knowledge of SM than males (aOR: 2.10; 95%CI: 1.64-2.71; p-value < 0.001), with no significant differences in practice (aOR: 1.24; 95%CI: 0.99 - 1.56; p-value = 0.065). Individuals working or studying in the medical field were significantly more knowledgeable about SM (aOR: 4.30; 95%CI: 3.27-5.69; p-value < 0.001) and more likely to practice SM (aOR: 1.65; 95%CI: 1.26-2.17; p-value < 0.001). The odds of SM decreased with favorable attitudes (aOR: 0.44; 95%CI: 0.36-0.55; p-value < 0.001) while surprisingly, knowledge level was not significantly contributing to SM practice (aOR: 1.15; 95%CI: 0.90-1.48; p-value = 0.268). CONCLUSIONS: SM is prevalent in Egypt, highlighting the importance of raising awareness and encouraging physician consultation as a priority. Governments, healthcare organizations, and educational institutions need to collaborate to provide the necessary support and resources.

Identification of novel laccase from cyanobacterium Microcystis flos-aquae and enhanced azo dye bioremediation potential.

Textile industries discharge up to 280,000 tons of dye waste annually, resulting in global pollution and health risks. In Nigeria and other African countries, persistent dyes threaten aquatic life and human health. This study introduces a cost-effective, enzyme-mediated bioremediation alternative using a novel laccase from the cyanobacteriumMicrocystis flos-aquae. This purified enzyme yielded 0.55 % (w/w)with significant activity at 40 °C and pH 4.00. Kinetic studies showed the dependence of M. flos-aquae laccase on Cu2+and its inhibition by EDTA and Fe2+. The efficacy of the enzyme was demonstrated through rapid decolorization of the azo dye Cibacron Brilliant Blue over a wide temperature and pH range. As this enzyme effectively decolorizes dyes across a broad temperature and pH range, it offers a promising solution for bioremediation of textile effluents.

Chemodiverse monoterpene indole alkaloids from Kopsia teoi, inhibitory potential against α-amylase, and their molecular docking studies.

Diabetes mellitus stands as a metabolic ailment marked by heightened blood glucose levels due to inadequate insulin secretion. The primary aims of this investigative inquiry encompassed the isolation of phytochemical components from the bark of Kopsia teoi, followed by the assessment of their α-amylase inhibition. The phytochemical composition of the K. teoi culminated in the discovery of a pair of new indole alkaloids; which are 16-epi-deacetylakuammiline N(4)-methylene chloride (akuammiline) (1), and N(1)-methoxycarbonyl-11-methoxy-12-hydroxy-Δ14-17-kopsinine (aspidofractinine) (2), together with five known compounds i.e. kopsiloscine G (aspidofractinine) (3), akuammidine (sarpagine) (4), leuconolam (aspidosperma) (5), N-methoxycarbonyl-12-methoxy-Δ16, 17-kopsinine (aspidofractinine) (6), and kopsininate (aspidofractinine) (7). All compounds were determined via spectroscopic analyses. The in vitro evaluation against α-amylase showed good inhibitory activities for compounds 5-7 with the inhibitory concentration (IC50) values of 21.7 ± 1.2, 34.1 ± 0.1, and 30.0 ± 0.8 µM, respectively compared with the reference acarbose (IC50 = 34.4 ± 0.1 µM). The molecular docking outputs underscored the binding interactions of compounds 5-7 ranging from -8.1 to -8.8 kcal/mol with the binding sites of α-amylase. Consequently, the outcomes highlighted the anti-hyperglycemic attributes of isolates from K. teoi.

An insight into the clinical learning environment of dental institutes: a study in the twin cities of Pakistan.

OBJECTIVE: To assess the perceptions of dental students regarding their clinical learning environment in an urban setting. METHODS: This descriptive, cross-sectional survey was conducted from March 2020 to May 2021 after approval from the ethics review committee of Islamic International Dental College, Islamabad, Pakistan. It comprised of clinical year students, house officers and postgraduate trainees from 6 dental teaching hospitals of Rawalpindi and Islamabad. Data was collected using a pre-validated instrument assessing the dental clinical learning environment. Data was analysed using SPSS 24. RESULTS: Of the 1030 students approached, 561(54.4%) responded. Of them, 448(80%) were girls, 234(41.7%) were 3rd year students, 110(19.6%) were 4th year students, 120(21.4%) were house officers and 97(17.3%) were postgraduate trainees. Female students had a better patient attitude and were more confident in their abilities to keep up with their peers (p<0.05). The students were content with the performance of their clinical teachers, with a mean score of 70.99+/-16.0, while the lowest score of 54.67+/-22.9 was for clinical infrastructure and materials. Students of Islamabad pointed out the lack of clinical materials and maintenance of equipment but noted better research opportunities compared to their Rawalpindi counterparts (p<0.05). CONCLUSIONS: The clinical learning environment for Islamabad and Rawalpindi cities individually was good. Overall, students were satisfied with their clinical teachers, learning and training experience. Dental materials, infrastructure and maintenance factors scored the lowest.

Burnout level in Pakistani dentists during COVID-19 pandemic: Cross-sectional national study.

Objective: This study aims to determine the prevalence and degree of Burnout during the COVID 19 pandemic in practicing Pakistani dentists. Introduction: The COVID-19 pandemic has significantly impacted dental practices worldwide, leading to increased stress and burnout among dental practitioners. Burnout, characterized by emotional exhaustion, depersonalization, and reduced personal accomplishment, can have detrimental effects on the quality of care and patient safety. Previous studies have shown high rates of burnout among healthcare workers, including dentists. The pandemic has added new challenges, such as financial losses and increased costs due to safety protocols. Recognizing and managing burnout is crucial to mitigate its severe consequences. By understanding the prevalence of burnout in this unique context, strategies can be developed to support dental practitioners and improve their well-being. Methods: A cross-sectional study was conducted using a 22-items based validated Maslach Burnout Inventory. The study was conducted between July and September 2021. Practicing dentists across Pakistan were approached via social media platforms. The questions were answered on a 7-point Likert scale. The sums of the scores were used as the evaluation criteria. Data analysis was done using SPSS version 24. Shapiro Wilk test was used to check normality of data. Mann Whitney U and Kruskal Wallis tests were utilized to analyze the differences in the prevalence of burnout amongst the different demographic groups. A P-value of <0.05 was considered as statistically significant. Results: Total of 282 dentists responded with 116 (41.1 %) male and 166 (58.9 %) female. Majority of the respondents were postgraduate residents (24.8 %), 47.9 % of the practitioners had 0-3 years of work experience, 48.6 % of the respondents were practicing in the Federal region, and 62.8 % of the subjects were between the age of 25-34. Emotional exhaustion was the major dimension of burnout identified in our study with 47.5 % of the population reporting high levels, while only 23 % of the population showed high levels of depersonalization and 29.4 % showed low sense of personal accomplishment. Conclusion: This study indicates a considerable percentage of burnout in the chosen sample. The mean scores of Emotional Exhaustion, Depersonalization and Diminished sense of personal accomplishment were all found to be in the moderate range, and that appropriate measures should be taken to manage it.

Seroprevalence of SARS-CoV-2 in Niger State: Pilot Cross-Sectional Study.

Background: The COVID-19 pandemic caused by SARS-CoV-2 is causing ongoing human and socioeconomic losses. Objective: To know how far the virus has spread in Niger State, Nigeria, a pilot study was carried out to determine the SARS-CoV-2 seroprevalence, patterns, dynamics, and risk factors in the state. Methods: A cross-sectional study design and clustered, stratified random sampling strategy were used to select 185 test participants across the state. SARS-CoV-2 IgG and IgM rapid test kits (colloidal gold immunochromatography lateral flow system) were used to determine the presence or absence of antibodies to the virus in the blood of sampled participants across Niger State from June 26 to 30, 2020. The test kits were validated using the blood samples of some of the Nigeria Center for Disease Control-confirmed positive and negative COVID-19 cases in the state. SARS-CoV-2 IgG and IgM test results were entered into the Epi Info questionnaire administered simultaneously with each test. Epi Info was then used to calculate the arithmetic mean and percentage, odds ratio, χ2 statistic, and regression at a 95% CI of the data generated. Results: The seroprevalence of SARS-CoV-2 in Niger State was found to be 25.4% (47/185) and 2.2% (4/185) for the positive IgG and IgM results, respectively. Seroprevalence among age groups, genders, and occupations varied widely. The COVID-19 asymptomatic rate in the state was found to be 46.8% (22/47). The risk analyses showed that the chances of infection are almost the same for both urban and rural dwellers in the state. However, health care workers, those who experienced flulike symptoms, and those who had contact with a person who traveled out of Nigeria in the last 6 months (February to June 2020) were at double the risk of being infected with the virus. More than half (101/185, 54.6%) of the participants in this study did not practice social distancing at any time since the pandemic started. Participants' knowledge, attitudes, and practices regarding COVID-19 are also discussed. Conclusions: The observed Niger State SARS-CoV-2 seroprevalence and infection patterns meansuggest that the virus has widely spread, far more SARS-CoV-2 infections have occurred than the reported cases, and there is a high asymptomatic COVID-19 rate across the state.

Self-efficacy and Online Learning Readiness of Undergraduate Dental Students in Pakistan During COVID-19 Pandemic.

OBJECTIVE: To investigate the correlation between general self-efficacy and online learning readiness among Pakistani undergraduate dental students. STUDY DESIGN: Cross-sectional study. Place and Duration of the Study: Riphah International University, Islamabad, between September 2020 and March 2021. METHODOLOGY: Using cluster sampling, three dental colleges of Islamabad and Rawalpindi were selected. Electronic questionnaires were sent to 750 students. The questionnaire was comprised of two instruments, General Self-Efficacy Scale (GSES), and Online Learning Readiness Scale (OLRS). GSES had 10-items with response measurement on four-point Likert scale, while the OLRS had 18 items in five different domains measured by five-point Likert scale. Data were analysed using SPSS-23. Correlation between dependent variables was calculated using linear regression analysis. RESULTS: The response rate was 59.3% with a predominant response from female students (82.2%) compared with male students (17.8%). The majority of responses were recorded from third year students (27.9%). The year four students' scores for GSE, computer and internet self-efficacy, and self-directed learning differed significantly from other students. The overall mean GSE score was 29.37+4.57. Regression indicated a low degree of correlation between GSE and the five domains of OLRS with r2 values ranging from 0.12 to 0.32. CONCLUSION: A weak to moderate correlation was found between self-efficacy and the five dimensions of online learning readiness among Pakistani undergraduate dental students as depicted by the r-values. KEY WORDS: Cross-sectional studies, Dental education, Dental students, Dentistry, Efficacy, Online learning, Questionnaire.

Levels of Genetic Variants Among Symptomatic Blastocystis Subtypes and their Relationship to Mucosal Immune Surveillance in the Precancerous Colons of Experimentally Infected Rats.

PURPOSE: The relationship between the genetic diversity of Blastocystis and immune surveillance in precancerous colons with blastocystosis is still under investigation. This study aimed to identify the genetic Blastocystis variants among 54 symptomatic human isolates and their relationship to mucosal immune surveillance in the precancerous polyps of experimentally infected rats. METHODS: Polymerase chain reaction and high-resolution melting (PCR/HRM) curves discriminated human symptomatic Blastocystis isolates into subtypes (STs)/intrasubtypes, which were orally administered to rats to induce experimental infection. Then, the mucosal immune responses of the infected colons were evaluated in relation to polyp formation through immunostaining to identify mucus MUC2 and determine mucosal immune cell (goblet, lymphocyte and mast) counts, secretory IgA levels and parasitic intestinal invasion. RESULTS: ST1, ST3, and ST4 were found in 18.5% (10/54), 54.7% (29/54), and 27.8% (15/54) of the samples, respectively. Then, the HRM curve discriminated ST3 into the wild, mutant, and heterozygous [17/54 (31.5%), 5/54 (9.3%), and 7/54 (12.9%)] intrasubtypes. ST1 and ST4 had no genetic variations. Precancerous polyps were detected in the colons of 40.5% of the infected rats. ST1 constituted 14.7% of these cases, while the wild, mutant, and heterozygous intrasubtypes of ST3 showed polyps in 12.9%, 5.5%, and 5.5% of cases, respectively. Only 1.9% of the polyps were related to ST4. MUC2 showed weak immunostaining in 44.5% of the infected colons, and 38.9% were polyp inducers. Low goblet cell numbers and high interepithelial lymphocyte counts were significantly associated with polyp formation, particularly with ST1 and wild ST3. Among the polyp inducers, high numbers of mast cells were detected in wild ST3 and ST4, while a low number was found with heterozygous ST3. The level of secretory IgA was low in polyp-inducing STs. Most of the results were statistically significant. CONCLUSION: Immunosurveillance showed a potential relationship between ST1 and the ST3 intrasubtypes and precancerous polyps. This relationship may provide insight into the prevention and/or development of new immunotherapeutic strategies to combat colorectal cancer.

Mitracarpus hirtus (L.) DC.: is a potential source for the exploitation of anticancer agents.

Mitracarpus hirtus (L.) DC. is a weed plant commonly used for the treatment of eczema. The potential of the plant to treat cancer has not been emphasized, hence the need to explore its anticancer potential. M. hirtus was extracted and subjected to petition with solvents of increasing polarity. Its cytotoxic potential was evaluated against MCF-7, HepG2, and HeLa cells using the Neutral red assay and further verified through morphological assessment and DNA fragmentation assay. Crude chloroform fraction (CCF) displayed a cytotoxic effect on all the cell lines with low IC50 concentrations ranging from 11-17.87 µg/mL. Morphological assessment of MCF-7 exposed to CCF indicates apoptotic cell death and is further confirmed by its DNA fragmentation. Our data suggest that M. hirtus is a potential source for mining anticancer agents.

DFT-based Raman spectral study of astaxanthin geometrical isomers.

Astaxanthin is a carotenoid widely used in food additives, nutritional product and medicines, which shows many physiological functions such as antioxidant, anti-inflammatory, anti-hypertensive and anti-diabetic activities. It has been recognized that astaxanthin has all-trans and nine cis isomers, and these geometrical isomers have very different biological activities. The process of selective enrichment, metabolism and isomerization of astaxanthin in animals remains to be studied. Therefore, identifying isomers and obtaining their structural parameters are important for understanding the active mechanism of different molecular isomers. Although the traditional methods such as high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) spectroscopy can be used to distinguish these isomers, these methods generally require considerable testing time, cost, sample volume, and hardly be applied in vivo. In this work, Raman spectroscopy combined with density functional theory (DFT) calculation was introduced to study different geometrical isomers of astaxanthin. The theoretical and experimental Raman spectra are in agreement, and we have demonstrated that all the known ten geometrical isomers of astaxanthin can be readily distinguished using this spectroscopic approach. The astaxanthin molecular vibrational modes, geometric structures, energies of ten geometric isomers are systematically scrutinized. Moreover, a lot of structural and Raman problems unsolved previously have been solved by the DFT-based spectral analysis. Therefore, this work provides an effective way for identification of different astaxanthin geometrical isomers, and may have important significance for promoting the research of astaxanthin isomers on biological property mechanisms and related applications in food molecular science.

Frequency of middle mesial canal in mandibular first molars and its association with various anatomic variables.

This study aimed to determine the frequency of the middle mesial canal in the mandibular first molars and its association with various anatomical features. Two experienced endodontists evaluated 149 CBCT images, containing n = 298 mandibular first molars and n = 298 mandibular second molars. Binary logistic regression was used to explore the relationship between the presence of middle mesial canal and other independent variables. The middle mesial canal was found in 7.7% (n = 23) of mandibular first molars and 11.4% of which exhibited adjacent C-shaped mandibular second molars. The presence of an adjacent C-shaped mandibular second molar was associated with a 3 times increased likelihood of finding a middle mesial canal (P = 0.048, OR: 3.108) in mandibular first molars. The middle mesial canal is an uncommon finding with a rare occurrence of bilateral presence in mandibular molars; however, an adjacent C-molar is an important predictor of middle mesial canal presence.

DFT and Raman study of all-trans astaxanthin optical isomers.

Astaxanthin (AST) is a xanthophyll carotenoid widely distributed in aquatic animals, which has many physiological functions such as antioxidant, anti-inflammatory, anti-hypertensive and anti-diabetic activities. AST has three optical isomers, including a pair of enantiomers (3S,3'S and 3R,3'R) and a meso form (3R,3'S). Different optical isomers have differences in a variety of physiological functions. Traditionally, High Performance Liquid Chromatography (HPLC) has been used to distinguish these isomers. In this work, it was found that Raman spectroscopy can be employed to distinguish the three optical isomers. The intensities of two Raman bands at 1190 and 1215 cm-1 of three isomers are different. Density Functional Theory (DFT) calculations are performed to analyze the spectral differences. The mainly occupied conformers of these three optical isomers are speculated and identified.

SERS Approach to Probe the Adsorption Process of Trace Volatile Benzaldehyde on Layered Double Hydroxide Material.

The study of the physicochemical process of volatile organic compound (VOC) adsorption on porous materials is significant for design and screening of adsorbent materials and treatment of VOCs. Traditional measurement methods for studying the adsorption process require lots of adsorbates and adsorbents and are time-consuming. We proposed a facile strategy to study the adsorption process of trace gaseous aldehydes on layered double hydroxide (LDH) using surface-enhanced Raman spectroscopy (SERS). We prepared a composite of Ag nanocubes@hollow Co-Ni LDH (AgNCs@Co-Ni LDH) with a strong adsorption capability and high SERS sensitivity. The adsorption properties of LDH for benzaldehyde in terms of general kinetics and isotherms were investigated. The kinetic adsorption process could be fitted better by the pseudo-first-order kinetics with a higher correlation coefficient than by the pseudo-second-order model, and the adsorption rate of 0.0308 min-1 was obtained from the fitting curve. The isotherm adsorption fits the Langmuir isotherm model, and its adsorption constant is 6.25 × 106 L/mol. Taking advantage of the excellent adsorptive performance and SERS activity, the AgNCs@Co-Ni LDH composite can be used as an effective SERS probe to detect gaseous aldehydes, and it shows a linear dynamic range (5-100 ppb) with a limit of detection reaching 1.83 ppb for benzaldehyde, better than that achieved by previous studies. Therefore, this work has not only established a new measurement method for probing the adsorption process with extremely low consumption of both adsorbates and adsorbents, but also may lay the groundwork for the construction of rapid and ultra-sensitive SERS sensors for probing VOCs in the future.

Extent of spongiofibrosis and length of strictures: Findings at sonourethrography and urethroplasty.

INTRODUCTION: The purpose of this study was to diagnose urethral stricture and to determine the extent of spongiofibrosis as well as the length of stricture using sonourethrography and compare it with intraoperative findings. PATIENTS AND METHODS: It was a cross sectional observational study from September 2017-August 2018. All patients who presented with urethral stricture, scheduled for urethroplasty, and consented to the study were enrolled. The extent of spongiofibrosis and length of strictures were determined at sonourethrography and subsequently at urethroplasty. Sensitivity, specificity, positive predictive value and negative predictive values of sonourethrography in the determination of length of stricture was done. Spearman correlation coefficient(r) was used to describe the association between the extent of spongiofibrosis found at sonourethrography and at urethroplasty. RESULTS: A total of 84 patients were evaluated during the study period. The median age at presentation was 45years. 81% of the patients had moderate spongiofibrosis on sonourethrography. There was a significant correlation of 71.4% between the extent of spongiofibrosis on sonourethrography and at urethroplasty. In evaluation for the length of strictures, sonourethrography had a sensitivity of 84.6% specificity of 82.7%, PPV of 68.7% and NPV 92.3%. CONCLUSION: Sonourethrography is a valuable tool in the evaluation of urethral strictures. Its radiation free readily available even in resource-poor settings and gives a good evaluation of extent of spongiofibrosis as well as the length of strictures. It's use in the preoperative evaluation of strictures may improve the outcome of the management of strictures.

A review of aptamer-based SERS biosensors: Design strategies and applications.

Surface-enhanced Raman spectroscopy, due to its high sensitivity, unique vibrational fingerprint identification of molecules and easy operation, has been extensively applied in different fields. Aptamers, being the unique single stranded DNA/RNA sequences that can specifically recognize and seize the target analytes, combined with Surface-enhanced Raman spectroscopy (SERS), can offer potent multiplex detection capacity with high specificity and sensitivity. In this review, we summarize and classify the general working strategies of different types of aptamer-based SERS biosensors with diversified protocols which either take aptamer conformational change as intrinsic reporter, or make use of various extrinsic Raman reporters in different sensor designs via on/off approach, sandwich-type and magnetic nanoparticles (NPs)-assisted approach, and catalytic reaction assisted approach with amplification of alternative Raman signals. The advantages, applications and perspectives of these aptamer-based SERS biosensors are also discussed.

Highly Sensitive Detection of Elevated Exosomal miR-122 Levels in Radiation Injury and Hepatic Inflammation Using an Aptamer-Functionalized SERS-Sandwich Assay.

Radiation-induced organ injury is one of the major fallouts noticed during radiotherapy treatment of malignancies and other detrimental radiation exposures. MicroRNA (miRNA), which is involved in multiple critical cellular processes, is released from the cells of damaged organs in cellular vesicles, commonly known as exosomes. Specifically, exosomal miR-122 is reported to be actively involved in radiation-actuated rectal and hepatic injuries or inflammation. In this work, we developed a surface-enhanced Raman spectroscopy (SERS) assay for the quantitative and targeted detection of exosomal miR-122 in mice after drug/radiation treatments. In particular, an aptamer-functionalized magnetic capturing element and Au shell nanoparticle (NP)-based SERS tags were utilized, which upon recognition of the target miRNA constituted a "sandwich" formation, with which an 8 fM limit of detection (LOD) could be achieved. Using this SERS assay, we further found that radiation injury led to the elevated expression of exosomal miR-122 in mice at 4 h postirradiation, confirmed by the quantitative real-time PCR method. It was demonstrated that the drug-induced hepatic inflammation could also be assessed via detecting miR-122 using this SERS method. As such, this work has demonstrated the achievement of a highly selective and sensitive probe of exosomal miRNA, which may thus open a gateway for promising usage in drug/radiation-induced inflammation.

Enhanced capacitive performance of cathodically reduced titania nanotubes pulsed deposited with Mn2O3 as supercapacitor electrode.

A facile and simple pulse electrodeposition method was employed to deposit Mn2O3 nanoparticles on cathodically reduced titania nanotubes (R-TNTs) at different deposition time in the range of 3-15 min to investigate the influence of mass loading of Mn2O3 on the electrochemical performance of Mn2O3/R-TNTs nanocomposite for supercapacitor application. Mn2O3 nanoparticles were deposited on circumference of R-TNTs as well as in the nanotubes as revealed by FESEM images for all the deposited time. XPS result confirmed the presence of MnO2 (Mn4+) and MnO (Mn2+) on the Mn2O3/R-TNTs composite which provide pseudocapacitive behaviour for the electrode. Mass loading of Mn2O3 increased linearly with deposition time as confirmed by EDX analysis. The sample deposited for 12 min exhibits the highest areal capacitance of 51 mF cm-2 (which is 22 times enhancement over R-TNTs) at a current density of 0.1 mA cm-2 and specific capacitance of 325 F g-1 at 6 A g-1. The sample also show a high-rate capability by retaining 80% of its capacitance even at higher current density of 30 A g-1. Interestingly, it retained 98% of the capacitance over 5000 charge discharge cycles at 10 A g-1 after initial drop to 95% at 200th cycles suggesting an excellent long-term chemical stability. A considerably low equivalent series resistance (ESR) and charge transfer resistance (R ct) of 9.6 Ω and 0.4 Ω respectively was deduced from electrochemical impedance spectroscopy (EIS) analysis indicating good conductivity and improved charge transfer efficiency of Mn2O3/R-TNTs nanocomposite.