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Sunitinib is a targeted therapy for colorectal cancer, which needs a precise dosage due to potential severe side effects from overdose. Therapeutic drug monitoring is crucial for maintaining optimal drug levels in body fluids. Traditional anticancer drug dose evalua­tion methods such as high-pressure liquid chromatography, liquid chromatography with mass spectrophotometry, and immunoassays are cumbersome. This study explores the utilization of electrochemical sensors on indigenously developed screen-printed electrodes for sunitinib malate monitoring. Differential pulse voltammetry, cyclic voltam­metry and chrono-amperometric studies were conducted in a conventional three-elec­trode system. An anodic peak current, indicative of sunitinib malate electro­oxi­dation, was observed around +0.45 V vs. Ag/AgCl reference electrode in 0.1 M PB of pH 7.4. Sen­sitivity, the limit of detection and method detection limit were determined as 0.386 µA µM-1 cm-2, 0.009 and 0.0108 µM, respectively. The response exhibited linearity (R2 = 0.990) with sunitinib concentration ranging from 0.08 to 88 μM with good reproducibility. DPV studies on real samples yielded acceptable recovery values. Electro­chemical sensors based on the screen-printed electrode present a promising approach for sunitinib monitoring, offering sensitivity, low limit of detection, and a wide linear range. Since the expected plasma concentration of sunitinib is much higher than the sensor detection range, it can be used for real sample analysis. Here developed methods could simplify and improve therapeutic drug monitoring in colorectal cancer treatment.

Purpose: Cognizant and well aware medical and nursing students are expected to influence and positively mold the eye donation rates in India. Keeping this in view, this study was designed to assess and compare eye donation awareness among medical and nursing students. Methods: A cross-sectional and comparative study undertaken on the occasion of eye donation fortnight among 112 medical and 115 nursing students. A pretested semi-structured questionnaire on eye donation was given to each student after getting informed consent. The software used for analysis of data was SPSS version 22.0. Results: All the medical students and 91.3% of nursing students (P < 0.0016) had heard about eye donation. Eye donation fortnight is celebrated every year to create awareness was known to 42% of medical students and 29.5% of nursing students (P < 0.05). Television, newspaper, magazines, and posters were found to be important sources of information in both groups. Eye donation can give vision to the blind was the primary motivational force both among medical and nursing students (P < 0.001). The ideal time of eye donation is within 6 h of death was known to 69% of medical students and 60.9% nursing students. Lack of awareness and objection of family members are the two significant perceived responses to non-donation in both groups. 88.4% of medical students and 79.1% of nursing students are willing to donate their eyes in future. Conclusion: The awareness of eye donation among medical students is better than nursing students. However, the willingness to pledge their eyes is almost equal in both groups.

A G protein-coupled receptors (GPCRs) phosphorylation assay for cell culture plates can be used for ligand profiling and inhibitor screening, as evidenced by the identification of two GRK inhibitor compounds.

Abstract Multi-receptor targeting has been proposed as a promising strategy for the development of opioid analgesics with fewer side effects. Cebranopadol and AT-121 are prototypical bifunctional ligands targeting the nociceptin/orphanin FQ peptide receptor (NOP) and µ-opioid receptor (MOP) that elicit potent analgesia in humans and nonhuman primates, respectively. Cebranopadol was reported to produce typical MOP-related side effects such as respiratory depression and reward, whereas AT-121 appeared to be devoid of these liabilities. However, the molecular basis underlying different side effect profiles in opioid analgesics remains unknown. Here, we examine agonist-induced receptor phosphorylation and G protein signaling profiles of a series of chemically diverse mixed MOP/NOP agonists, including cebranopadol and AT-121. We found that these compounds produce strikingly different MOP phosphorylation profiles. Cebranopadol, AT-034 and AT-324 stimulated extensive MOP phosphorylation, whereas AT-201 induced selective phosphorylation at S375 only. AT-121, on the other hand, did not promote any detectable MOP phosphorylation. Conversely, none of these compounds was able to elicit strong NOP phosphorylation and low NOP receptor phosphorylation correlated with partial agonism in a GIRK-channel assay. Our results suggest a close correlation between MOP receptor phosphorylation and side effect profile. Thus, bifunctional MOP/NOP opioid ligands combining low efficacy G protein signaling at both NOP and MOP with no detectable receptor phosphorylation appear to be devoid of side-effects such as respiratory depression, abuse liability or tolerance development, as with AT-121.

Purpose: Congenital ocular anomalies are rare but important cause of childhood blindness. This study aimed to observe the clinical patterns of congenital ocular anomalies in the pediatric age group (0 to 5 years) and its association with various demographic parameters. Methods: Hospital-based cross-sectional study done on all pediatric patients in the 0-to-5-year age group presenting with congenital ocular anomalies to the Ophthalmology department of a tertiary care hospital in Eastern India between October 2018 and October 2020. Thorough clinical history was obtained, and comprehensive ocular examination was done in each case. Results: A total of 5686 patients in the 0 to 5 years age group attended the eye OPD during the study period. Congenital ocular anomalies were seen in 140 patients. The prevalence of ocular anomalies was 2.46%. Average age of patients was 3.32 ± 1.42 years. There were 74 (52.9%) males and 66 (47.1%) females. Unilateral and bilateral involvement was seen in 100 (71.45%) and 40 (28.6%) cases, respectively. Antenatal period was uneventful in 92.14% cases. Decreased vision was the most common presentation (40%). Congenital nasolacrimal duct obstruction was the most common anomaly seen in 29 (20.71%) cases followed by congenital cataract in 21 (15%) cases. Conclusion: Few of the congenital ocular anomalies can be prevented by increasing community awareness. Findings of the study can act as a reference guide for clinicians and health professionals for counseling and health planning.

Abstract The dopamine D2 receptor (D2R) is the target of drugs used to treat the symptoms of Parkinson’s disease and schizophrenia. The D2R is regulated through its interaction with and phosphorylation by G protein receptor kinases (GRKs) and interaction with arrestins. More recently, D2R arrestin-mediated signaling has been shown to have distinct physiological functions to those of G protein signalling. Relatively little is known regarding the patterns of D2R phosphorylation that might control these processes. We aimed to generate antibodies specific for intracellular D2R phosphorylation sites to facilitate the investigation of these mechanisms. We synthesised double phosphorylated peptides corresponding to regions within intracellular loop 3 of the hD2R and used them to raise phosphosite-specific antibodies to capture a broad screen of GRK-mediated phosphorylation. We identify an antibody specific to a GRK2/3 phosphorylation site in intracellular loop 3 of the D2R. We compared measurements of D2R phosphorylation with other measurements of D2R signalling to profile selected D2R agonists including previously described biased agonists. These studies demonstrate the utility of novel phosphosite-specific antibodies to investigate D2R regulation and signalling.

Abstract The δ-opioid receptor (DOP) is an attractive pharmacological target due to its potent analgesic, anxiolytic and anti-depressant activity in chronic pain models. However, some but not all selective DOP agonists also produce severe adverse effects such as seizures. Thus, the development of novel agonists requires a profound understanding of their effects on DOP phosphorylation, post-activation signaling and dephosphorylation. Here we show that agonist-induced DOP phosphorylation at threonine 361 (T361) and serine 363 (S363) proceeds with a temporal hierarchy, with S363 as primary site of phosphorylation. This phosphorylation is mediated by G protein-coupled receptor kinases 2 and 3 (GRK2/3) followed by DOP endocytosis and desensitization. DOP dephosphorylation occurs within minutes and is predominantly mediated by protein phosphatases (PP) 1α and 1β. A comparison of structurally diverse DOP agonists and clinically used opioids demonstrated high correlation between G protein-dependent signaling efficacies and receptor internalization. In vivo, DOP agonists induce receptor phosphorylation in a dose-dependent and agonist-selective manner that could be blocked by naltrexone in DOP-eGFP mice. Together, our studies provide novel tools and insights for ligand-activated DOP signaling in vitro and in vivo and suggest that DOP agonist efficacies may determine receptor post-activation signaling.

Veldoreotide, a somatostatin analogue, binds to the somatostatin receptors (SSTR) 2, 4, and 5. The current aim was to assess its pharmacological activity as an SSTR4 agonist. G-protein signaling was assessed using a fluorescence-based membrane potential assay in human embryonic kidney 293 (HEK293) cells stably co-expressing G-protein-coupled inwardly rectifying potassium 2 channels and the individual SSTR2, SSTR4, and SSTR5, and in human BON-1 cells stably expressing these SSTRs. Veldoreotide effects on chromogranin A (CgA) secretion and cell proliferation were examined in BON-1 cells. In HEK293 transfected cells, veldoreotide showed a high efficacy for activating the SSTR4; octreotide and pasireotide had little activity (Emax, 99.5% vs. 27.4% and 52.0%, respectively). Veldoreotide also activated SSTR2 and SSTR5 (Emax, 98.4% and 96.9%, respectively). In BON-1 cells, veldoreotide activated SSTR2, SSTR4, and SSTR5 with high potency and efficacy. CgA secretion was decreased to a greater degree in the BON-1 cells expressing SSTR4 versus the cells expressing SSTR2 and SSTR5 (65.3% vs. 80.3% and 77.6%, respectively). In the BON-1 cells expressing SSTR4, veldoreotide inhibited cell proliferation more than somatostatin SS-14 (71.2% vs. 79.7%) and to a similar extent as the SSTR4 agonist J-2156 in the presence of SSTR2 and SSTR5 antagonists. Veldoreotide is a full agonist of SSTR2, SSTR4, and SSTR5.

Vitamins play a crucial role in cellular functions like cell cycling and proliferation, differentiation, and apoptosis. These also help in the induction of cell cycle arrest and/or apoptosis. They can inhibit normal prostatic epithelial cell growth and might be helpful for the prevention of prostate cancer (PCa). Many essential vitamins including the fat-soluble vitamins (vitamin A, vitamin D, vitamin E, and vitamin K) and the water-soluble vitamins (vitamin B complexes and vitamin C) have a huge impact on the inhibition of growth and progression of PCa. Vitamins show anticancer properties and are involved in regulatory processes like the DNA repairing process, which inhibit the growth of PCa. Consumption of multivitamins prevents methylation of cancer cells and possesses an enormous potential that can be applied for the prevention as well as in the management of PCa. They have a great role in the inhibition of different signalling pathways involved in PCa. Moreover, they have also displayed a significant role in targeting of PCa with various nanocarrier systems. This review encompasses the recent studies about the individual actions of different vitamins and vitamin analogs, the combination of vitamins, and their efficient functions in various therapeutic and targeting approaches for PCa., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)