419 results on '"Sanyal, R."'
Search Results
102. A0141 - Harnessing artificial intelligence for enhanced renal analysis: Automated detection of hydronephrosis and precise kidney segmentation.
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Alexa, R., Kranz, J., Murillo, L.F.C., Kramann, R., Kuppe, C., Sanyal, R., Hayat, S., Hoffmann, M., and Saar, M.
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ARTIFICIAL intelligence , *HYDRONEPHROSIS , *KIDNEYS - Published
- 2024
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103. Usefulness of Transesophageal Echocardiography in the Diagnosis of Ventricular Septal Rupture Secondary to Acute Myocardial Infarction
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Ballal, R. S., Sanyal, R. S., Nanda, N. C., and Mahan, E. F.
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- 1993
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104. Vitamin E Therapy in Dystrophic Epidermolysis Bullosa
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Sehgal, V. N. and Sanyal, R. K.
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TO THE EDITOR.— Dystrophic epidermolysis bullosa, a rare hereditary disorder, is characterized by the formation of bullae over the sites of friction. The clinical features of the condition have been described elsewhere.1,2 Various drugs, like corticosteroids,3 amino acids,4 and chloroquine phosphate,5 have been used but without beneficial effects. Vitamin E therapy in a case of dystrophic epidermolysis bullosa was first suggested by Price,6 later on commended by Wilson,7 and by Ayers and Mihan.8 A trial of vitamin E, (DL-alpha tocopheryl [Ephynal]) acetate therapy was undertaken in three cases of dystrophic epidermolysis bullosa with beneficial results. REPORT OF CASES Vitamin E acetate was administered in oral dosages of 300 to 600 international units (IU) daily in these cases. The treatment was started May 21, 1971, and continued until Sept 29. A remarkable improvement was evident by the regression of the existing skin lesions
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- 1972
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105. PREFACE TO SANYAL'S BOOK.
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Sanyal, R. B.
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- 1992
106. THE HUNTING LEOPAED.
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Sanyal, R. B.
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- 1986
107. Leaf growth in third dimension: a perspective of leaf thickness from genetic regulation to ecophysiology.
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Aneja P, Sanyal R, and Ranjan A
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Leaf thickness, the leaf growth in the third dimension as quantified by the distance between the adaxial and abaxial surface, is an indispensable aspect of leaf development. The fitness of a plant is strongly influenced by leaf thickness via modulation of major physiological processes, including photosynthesis and water use efficiency. The cellular basis of leaf thickness by alterations in either cell size or the number of cell layers is envisaged using Arabidopsis leaf thickness mutants, such as angustifolia (an) and rotundifolia (rot). Environmental factors coordinate with endogenous signaling mechanisms to exhibit leaf thickness plasticity. Plants growing in different ecological and environmental regimes show different leaf thickness attributes. However, genetic and molecular understandings of leaf thickness regulation remain largely limited. In this review, we highlight how cellular growth is transposed to fine-tune the leaf thickness via the integration of potential cues and molecular players. We further discuss the physiological significance of leaf thickness plasticity to the environmental cues that might serve as ecological adaptation enabling the plants to withstand future climatic conditions. Taken together, we seek to bridge the genetics and molecular biology of leaf thickness to its physiological significance so that leaf thickness can be systemically targeted in crop improvement programs., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)
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- 2024
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108. Tenecteplase versus alteplase for acute stroke within 4·5 h of onset (ATTEST-2): a randomised, parallel group, open-label trial.
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Muir KW, Ford GA, Ford I, Wardlaw JM, McConnachie A, Greenlaw N, Mair G, Sprigg N, Price CI, MacLeod MJ, Dima S, Venter M, Zhang L, O'Brien E, Sanyal R, Reid J, Sztriha LK, Haider S, Whiteley WN, Kennedy J, Perry R, Lakshmanan S, Chakrabarti A, Hassan A, Marigold R, Raghunathan S, Sims D, Bhandari M, Wiggam I, Rashed K, and Douglass C
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- Humans, Male, Female, Aged, Middle Aged, Treatment Outcome, Aged, 80 and over, Prospective Studies, Stroke drug therapy, Time-to-Treatment, Tenecteplase therapeutic use, Tenecteplase administration & dosage, Tissue Plasminogen Activator therapeutic use, Tissue Plasminogen Activator administration & dosage, Fibrinolytic Agents therapeutic use, Fibrinolytic Agents administration & dosage, Ischemic Stroke drug therapy
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Background: Tenecteplase has potential benefits over alteplase, the standard agent for intravenous thrombolysis in acute ischaemic stroke, because it is administered as a single bolus and might have superior efficacy. The ATTEST-2 trial investigated whether tenecteplase was non-inferior or superior to alteplase within 4·5 h of onset., Methods: We undertook a prospective, randomised, parallel-group, open-label trial with masked endpoint evaluation in 39 UK stroke centres. Previously independent adults with acute ischaemic stroke, eligible for intravenous thrombolysis less than 4·5 h from last known well, were randomly assigned 1:1 to receive intravenous alteplase 0·9 mg/kg or tenecteplase 0·25 mg/kg, by use of a telephone-based interactive voice response system. The primary endpoint was the distribution of the day 90 modified Rankin Scale (mRS) score and was analysed using ordinal logistic regression in the modified intention-to-treat population. We tested the primary outcome for non-inferiority (odds ratio for tenecteplase vs alteplase non-inferiority limit of 0·75), and for superiority if non-inferiority was confirmed. Safety outcomes were mortality, symptomatic intracranial haemorrhage, radiological intracranial haemorrhage, and major extracranial bleeding. The trial was prospectively registered on ClinicalTrials.gov (NCT02814409)., Findings: Between Jan 25, 2017, and May 30, 2023, 1858 patients were randomly assigned to a treatment group, of whom 1777 received thrombolytic treatment and were included in the modified intention-to-treat population (n=885 allocated tenecteplase and n=892 allocated alteplase). The mean age of participants was 70·4 (SD 12·9) years and median National Institutes of Health Stroke Scale was 7 (IQR 5-13) at baseline. Tenecteplase was non-inferior to alteplase for mRS score distribution at 90 days, but was not superior (odds ratio 1·07; 95% CI 0·90-1·27; p value for non-inferiority<0·0001; p=0·43 for superiority). 68 (8%) patients in the tenecteplase group compared with 75 (8%) patients in the alteplase group died, symptomatic intracerebral haemorrhage (defined by SITS-MOST criteria) occurred in 20 (2%) versus 15 (2%) patients, parenchymal haematoma type 2 occurred in 37 (4%) versus 26 (3%) patients, post-treatment intracranial bleed occurred in 94 (11%) versus 78 (9%) patients, significant extracranial haemorrhage occurred in 13 (1%) versus six (1%) patients, respectively, and angioedema occurred in six (1%) participants in both groups., Interpretation: Tenecteplase 0·25 mg/kg was non-inferior to 0·9 mg/kg alteplase within 4·5 h of symptom onset in acute ischaemic stroke. Easier administration of tenecteplase, especially in the context of interhospital transfers, indicates that tenecteplase should be preferred to alteplase for thrombolysis in acute ischaemic stroke. The ATTEST-2 population was large and representative of thrombolysis-eligible patients in the UK and, together with findings from other trials, provides robust evidence supporting the introduction of tenecteplase in preference to alteplase., Funding: The Stroke Association and British Heart Foundation., Competing Interests: Declaration of interests KWM reports lecture and advisory board fees from Boehringer Ingelheim; lecture fees from Brainomix and IschemaView; and consultancy fees from Abbvie, Biogen, Hyperfine, Lumosa, and Woolsey. GAF reports personal remuneration for advisory board or steering committee activity from CSL Behring; educational activities from Bayer; and his employer (University of Oxford and Oxford University Hospitals NHS Foundation Trust) has received remuneration for consultancy with AstraZeneca. IF reports research grants to the University of Glasgow from The Stroke Association and the British Heart Foundation. JMW reports academic research grants but no industry, advisory or speaker fees or stock interests. AM reports research grants to the University of Glasgow from The Stroke Association and the British Heart Foundation. NG reports research grants to the University of Glasgow from The Stroke Association and the British Heart Foundation. GM reports personal remuneration for consultancy with Canon Medical Research Europe. MJM reports advisory board and educational meeting remuneration from Astra Zeneca. WNW reports drafting the European Stroke Organisation guideline for thrombolysis; and Data Monitoring Committee for TEMPO-2. AH reports being a clinical advisor to the Peninsula Technology Assessment Group, University of Exeter Medical School (External Advisory Group National Institute for Health & Care Excellence Technology Appraisal of Tenecteplase for treating acute ischaemic stroke, NICE reference number ID6306), all unpaid. MB reports research meeting remuneration for the LIBREXIA trial from Janssen and Bristol Myers Squibb. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)
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- 2024
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109. Is video interpretation compromising care for the hearing loss population?
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Mastropierro J, Sanyal R, Heiser A, Gjini E, and Noonan K
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Objective: The convergence of hearing impairment and language barriers presents unique communication challenges to patients and practicing otolaryngologists. Limited data exist comparing interpretation methods for patients with hearing loss. Patients with hearing loss rely on visual cues, lip-reading, written communication, and/or comprehensive interaction techniques, which may encounter limitations by remote services. Herein, we examine patient and otolaryngology provider satisfaction, cost, and encounter efficiency between virtual and in-person interpretation among adults who speak Mandarin and Cantonese., Methods: This study is a prospective, randomized controlled trial in patients with moderate-to-severe bilateral hearing loss, Limited English Proficiency, and a primary language of Mandarin or Cantonese. Fifty-two patients were randomized to either in-person or virtual interpretation conditions. Patient satisfaction was measured using an 8-item Likert scale assessing communication effectiveness, encounter efficiency, and overall quality. Otolaryngology provider satisfaction was measured using a 1-item Likert scale. Encounter time, cost, and communication difficulty were measured and compared using independent sample t-tests., Results: Patient and otolaryngology provider satisfaction scores were significantly higher with in-person interpretation (p < 0.05 for 7 of 8 patient items; physician mean score 4.9, p < 0.001, r = 0.54) compared to virtual interpretation (physician mean 3.8) conditions, while overall quality of the encounter remained the same. There was no significant difference in the length of encounters or in the number of times patients requested interpreter repetition between groups. A difference in average cost existed for in-person interpretation ($14.50) compared to video interpretation ($25) services for an average length appointment., Conclusion: Patients and otolaryngologists reported higher overall satisfaction with in-person compared to virtual interpretation services. In-person interpretation yielded better comprehension in the hearing loss population among Mandarin and Cantonese-speaking patients and demonstrated a cost advantage over virtual interpretation., Competing Interests: Declaration of competing interest The authors have no funding, financial relationships, or conflicts of interest to disclose., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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110. Theranostic nanogels: multifunctional agents for simultaneous therapeutic delivery and diagnostic imaging.
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Altinbasak I, Alp Y, Sanyal R, and Sanyal A
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- Humans, Animals, Diagnostic Imaging methods, Drug Carriers chemistry, Drug Delivery Systems, Multifunctional Nanoparticles chemistry, Theranostic Nanomedicine, Nanogels chemistry, Neoplasms diagnostic imaging, Neoplasms drug therapy
- Abstract
In recent years, there has been a growing interest in multifunctional theranostic agents capable of delivering therapeutic payloads while facilitating simultaneous diagnostic imaging of diseased sites. This approach offers a comprehensive strategy particularly valuable in dynamically evolving diseases like cancer, where combining therapy and diagnostics provides crucial insights for treatment planning. Nanoscale platforms, specifically nanogels, have emerged as promising candidates due to their stability, tunability, and multifunctionality as carriers. As a well-studied subgroup of soft polymeric nanoparticles, nanogels exhibit inherent advantages due to their size and chemical compositions, allowing for passive and active targeting of diseased tissues. Moreover, nanogels loaded with therapeutic and diagnostic agents can be designed to respond to specific stimuli at the disease site, enhancing their efficacy and specificity. This capability enables fine-tuning of theranostic platforms, garnering significant clinical interest as they can be tailored for personalized treatments. The ability to monitor tumor progression in response to treatment facilitates the adaptation of therapies according to individual patient responses, highlighting the importance of designing theranostic platforms to guide clinicians in making informed treatment decisions. Consequently, the integration of therapy and diagnostics using theranostic platforms continues to advance, offering intelligent solutions to address the challenges of complex diseases such as cancer. In this context, nanogels capable of delivering therapeutic payloads and simultaneously armed with diagnostic modalities have emerged as an attractive theranostic platform. This review focuses on advances made toward the fabrication and utilization of theranostic nanogels by highlighting examples from recent literature where their performances through a combination of therapeutic agents and imaging methods have been evaluated.
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- 2024
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111. Redox-Responsive "Catch and Release" Cryogels: A Versatile Platform for Capture and Release of Proteins and Cells.
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Calik F, Degirmenci A, Maouati H, Sanyal R, and Sanyal A
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- Animals, Concanavalin A chemistry, Concanavalin A metabolism, Methacrylates chemistry, Mice, Mannose chemistry, Immobilized Proteins chemistry, Immobilized Proteins metabolism, Sulfhydryl Compounds chemistry, Streptavidin chemistry, Streptavidin metabolism, Proteins chemistry, Proteins metabolism, Biotin chemistry, Biotin metabolism, Biotin analogs & derivatives, Porosity, Cryogels chemistry, Oxidation-Reduction, Polyethylene Glycols chemistry
- Abstract
Macroporous cryogels are attractive scaffolds for biomedical applications, such as biomolecular immobilization, diagnostic sensing, and tissue engineering. In this study, thiol-reactive redox-responsive cryogels with a porous structure are prepared using photopolymerization of a pyridyl disulfide poly(ethylene glycol) methacrylate (PDS-PEG-MA) monomer. Reactive cryogels are produced using PDS-PEG-MA and hydrophilic poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) monomers, along with a PEG-based cross-linker and photoinitiator. Functionalization of cryogels using a fluorescent dye via the disulfide-thiol exchange reactions is demonstrated, followed by release under reducing conditions. For ligand-mediated protein immobilization, first, thiol-containing biotin or mannose is conjugated onto the cryogels. Subsequently, fluorescent dye-labeled proteins streptavidin and concanavalin A (ConA) are immobilized via ligand-mediated conjugation. Furthermore, we demonstrate that the mannose-decorated cryogel could capture ConA selectively from a mixture of lectins. The efficiency of protein immobilization could be easily tuned by changing the ratio of the thiol-sensitive moiety in the scaffold. Finally, an integrin-binding cell adhesive peptide is attached to cryogels to achieve successful attachment, and the on-demand detachment of integrin-receptor-rich fibroblast cells is demonstrated. Redox-responsive cryogels can serve as potential scaffolds for a variety of biomedical applications because of their facile synthesis and modification.
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- 2024
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112. Spatio-temporal expression of polyphenol oxidase unveils the dynamics of L-DOPA accumulation in faba bean ( Vicia faba L.).
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Jena S, Sanyal R, Jawed DM, Sengupta K, Pradhan B, Sinha SK, Sarkar B, Kumar S, Lenka SK, Naskar S, Bhadana VP, and Bishi SK
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Faba bean ( Vicia faba L.) is a winter season grain legume and a rich source of the anti-parkinson drug, L-3,4-dihydroxyphenylalanine (L-DOPA). The biosynthesis of L-DOPA in plants is not uniform and remains largely unexplored. While the hydroxylase activities of Tyrosine Hydroxylase (TH), the Cytochrome P450 (CYP450) class of enzymes, and Polyphenol Oxidases (PPOs) on tyrosine substrate have been reported in plants, only the roles of PPOs in L-DOPA biosynthesis have been recently established in velvet bean ( Mucuna pruriens ). To understand the differential accumulation of L-DOPA in different tissues of faba bean, profiling of L-Tyrosine, L-DOPA, Tyramine, and Dopamine in different tissues was performed. Differential accumulation of L-DOPA depended on tissue type and maturity. Furthermore, dopamine biosynthesis through L-DOPA from L-Tyr was confirmed in faba bean. The expression analysis of PPOs in leaf and flower tissues revealed the selective induction of only four ( HePPO-2 , HePPO-7 , HePPO-8b , and HePPO-10 ) out of ten genes encoding different PPOs mined from the faba bean genome. Higher accumulation of L-DOPA in young leaves and flower buds than in mature leaves and flowers was accompanied by significantly higher expression of HePPO-10 and HePPO-7 , respectively. The role of various transcription factors contributing to such metabolite dynamics was also predicted. Further exploration of this mechanism using a multi-omics approach can provide meaningful insight and pave the way for enhancing L-DOPA content in crops., Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-024-01449-2., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Prof. H.S. Srivastava Foundation for Science and Society 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)
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- 2024
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113. Metal-Free Click-Chemistry: A Powerful Tool for Fabricating Hydrogels for Biomedical Applications.
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Degirmenci A, Sanyal R, and Sanyal A
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- Click Chemistry, Metals, Drug Delivery Systems, Hydrogels chemistry, Polymers chemistry
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Increasing interest in the utilization of hydrogels in various areas of biomedical sciences ranging from biosensing and drug delivery to tissue engineering has necessitated the synthesis of these materials using efficient and benign chemical transformations. In this regard, the advent of " click " chemistry revolutionized the design of hydrogels and a range of efficient reactions was utilized to obtain hydrogels with increased control over their physicochemical properties. The ability to apply the " click " chemistry paradigm to both synthetic and natural polymers as hydrogel precursors further expanded the utility of this chemistry in network formation. In particular, the ability to integrate clickable handles at predetermined locations in polymeric components enables the formation of well-defined networks. Although, in the early years of " click " chemistry, the copper-catalyzed azide-alkyne cycloaddition was widely employed, recent years have focused on the use of metal-free " click " transformations, since residual metal impurities may interfere with or compromise the biological function of such materials. Furthermore, many of the non-metal-catalyzed " click " transformations enable the fabrication of injectable hydrogels, as well as the fabrication of microstructured gels using spatial and temporal control. This review article summarizes the recent advances in the fabrication of hydrogels using various metal-free " click " reactions and highlights the applications of thus obtained materials. One could envision that the use of these versatile metal-free " click " reactions would continue to revolutionize the design of functional hydrogels geared to address unmet needs in biomedical sciences.
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- 2024
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114. Corrigendum to 'Cancer chemotherapy and beyond: Current status, drug candidates, associated risks and progress in targeted therapeutics' [Genes & Diseases 10 (2023) 1367-1401].
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Anand U, Dey A, Singh Chandel AK, Sanyal R, Mishra A, Pandey DK, De Falco V, Upadhyay A, Kandimalla R, Chaudhary A, Dhanjal JK, Dewanjee S, Vallamkondu J, and Pérez de la Lastra JM
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[This corrects the article DOI: 10.1016/j.gendis.2022.02.007.]., (© 2024 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.)
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- 2024
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115. Prospective Validation of ThyroSPEC Molecular Testing of Indeterminate Thyroid Nodule Cytology Following Diagnostic Pathway Optimization.
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Stewardson P, Eszlinger M, Wu J, Khalil M, Box A, Perizzolo M, Punjwani Z, Ziehr B, Sanyal R, Demetrick DJ, and Paschke R
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- Humans, Mutation, Molecular Diagnostic Techniques, Retrospective Studies, Thyroid Nodule diagnostic imaging, Thyroid Nodule genetics, Thyroid Neoplasms diagnosis, Thyroid Neoplasms genetics, Thyroid Neoplasms pathology
- Abstract
Background: Molecular testing for cytologically indeterminate thyroid nodules (ITNs) is often reported with incomplete data on clinical assessment and ultrasound malignancy risk (USMR) stratification. This study aimed to clinically validate the diagnostic accuracy of a novel molecular test, assess the incremental preoperative malignancy risk of other clinical factors, and measure the impacts of introducing molecular testing at the population level. Methods: Comprehensive clinical data were collected prospectively for the first 615 consecutive patients with ITNs in a centralized health care system following implementation of a reflexive molecular test. Clinical data include patient history, method of nodule discovery, clinical assessment, USMR, cytology, molecular testing, and surgery or follow-up along with surgeon notes on surgical decision-making. Accuracy of molecular testing and the impact of the introduction of molecular testing were calculated. A multivariable regression model was developed to identify which clinical factors have the most diagnostic significance for ITNs. Results: A locally developed, low-cost molecular test achieved a negative predictive value (NPV) of 76-91% [confidence interval, CI 66-95%] and a positive predictive value (PPV) of 46-65% [CI 37-75%] in ITNs using only residual material from standard liquid cytology fine-needle aspiration (FNA). Sensitivity was highest (80%; [CI 63-92%]) in the American Thyroid Association (ATA) intermediate-suspicion ultrasound category, and lowest (46%; [CI 19-75%]) in the ATA high-suspicion ultrasound category. Following implementation of molecular testing, diagnostic yield increased by 14% ( p = 0.2442) and repeat FNAs decreased by 24% ( p = 0.05). Mutation was the primary reason for surgery in 76% of resected, mutation-positive patients. High-risk mutations were associated with a 58% ( p = 0.0001) shorter wait for surgery. Twenty-six percent of patients with a negative molecular test result underwent surgery. Multivariable regression highlighted molecular testing and USMR as significantly associated with malignancy. Conclusions: Molecular testing improves preoperative risk stratification but requires further stratification for intermediate-risk mutations. Incorporation of clinical factors (especially USMR) with molecular testing may increase the sensitivity for detection of malignancy. Introduction of molecular testing offers some clinical benefits even in a low resection rate setting, and directly influences surgical decision-making. This study illustrates the importance of the local diagnostic pathway in ensuring appropriate integrated use of molecular testing for best outcomes.
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- 2023
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116. Porous Microgels for Delivery of Curcumin: Microfluidics-Based Fabrication and Cytotoxicity Evaluation.
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Orbay S, Sanyal R, and Sanyal A
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Polymeric microgels, fabricated via microfluidic techniques, have garnered significant interest as versatile drug delivery carriers. Despite the advances, the loading and release of hydrophobic drugs such as curcumin from polymeric microgels is not trivial. Herein, we report that effective drug loading can be achieved by the design of porous particles and the use of supramolecular cyclodextrin-based curcumin complexes. The fabrication of porous microgels through the judicious choice of chemical precursors under flow conditions was established. The evaluation of the curcumin loading dependence on the porosity of the microgels was performed. Microgels with higher porosity exhibited better curcumin loading compared to those with lower porosity. Curcumin-loaded microgels released the drug, which, upon internalization by U87 MG human glioma cancer cells, induced cytotoxicity. The findings reported here provide valuable insights for the development of tailored drug delivery systems using a microfluidics-based platform and outline a strategy for the effective delivery of hydrophobic therapeutic agents such as curcumin through supramolecular complexation.
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- 2023
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117. A case report of infanticide in rural Nepal: Sociocultural perspectives and forensic considerations.
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Gyawali L, Atreya A, Kuinkel P, Sanyal R, and Shah A
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This case highlights the complex interplay of mental health, stigma, and lack of contraceptive access underlying tragic instances of infanticide. Comprehensive medicolegal investigation paired with cross-sector efforts to expand reproductive services and transform cultural attitudes is crucial to protect vulnerable women and children., Competing Interests: The authors declare that they have no conflict of interest regarding the publication of this case report., (© 2023 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.)
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- 2023
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118. Biotechnology of Passiflora edulis: role of Agrobacterium and endophytic microbes.
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Sanyal R, Pandey S, Nandi S, Mondal R, Samanta D, Mandal S, Manokari M, Mishra T, Dhama K, Pandey DK, Shekhawat MS, and Dey A
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- Biotechnology, Flavonoids, Glycosides, Agrobacterium genetics, Passiflora genetics
- Abstract
Two forms of the genus Passiflora, belonging to the Passifloraceae family, are commonly called yellow and purple passion. These perennial woody climbers are found in the cooler regions at higher altitudes and in lowlands of tropical areas. The presence of alkaloids, terpenes, stilbenes, flavonoids, glycosides, carotenoids, etc. in different parts of the plant provides several pharmacological properties. Because of the various uses in foods and pharmaceuticals, in vitro propagation of this genus has been performed hugely and is of great interest to researchers. From different explants via direct organogenesis under controlled aseptic conditions, callus, root, shoot, and somatic embryos are induced successfully. Different PGRs are augmented in the media for the rapid multiplication or organogenesis, especially, the high ratio of cytokinin and auxin in the basal media efficiently regenerates the shoot and root respectively. The in vitro regenerated plantlets are then acclimatized and hardened properly before transferring to the field conditions. Thus, the present first of its kind review on P. edulis exclusively encompasses the wide applications of biotechnology for this species alongside its organogenesis, embryogenesis, cytology, and endophytic microbes with special emphasis on the role of genetic transformation studies mediated by Agrobacterium sp. KEY POINTS: • Critical assessment on in vitro biotechnology in P. edulis. • Agrobacterium-mediated transformation in P. edulis. • Role of endophytic microbes in P. edulis., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2023
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119. Plug-and-Play Biointerfaces: Harnessing Host-Guest Interactions for Fabrication of Functional Polymeric Coatings.
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Degirmenci A, Sanyal R, and Sanyal A
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- Ligands, Mannose, Polymers chemistry
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Polymeric surface coatings capable of effectively integrating desired functional molecules and ligands are attractive for fabricating bio-interfaces necessary for various applications. Herein, we report the design of a polymeric platform amenable to such modifications in a modular fashion through host-guest chemistry. Copolymers containing adamantane (Ada) moieties, diethylene glycol (DEG) units, and silyloxy groups to provide functionalization handles, anti-biofouling character, and surface attachment, respectively, were synthesized. These copolymers were employed to modify silicon/glass surfaces to enable their functionalization using beta-cyclodextrin (βCD) containing functional molecules and bioactive ligands. Moreover, surface functionalization could be spatially controlled using a well-established technique like microcontact printing. Efficient and robust functionalization of polymer-coated surfaces was demonstrated by immobilizing a βCD-conjugated fluorescent rhodamine dye through the specific noncovalent binding between Ada and βCD units. Furthermore, biotin, mannose, and cell adhesive peptide-modified βCD were immobilized onto the Ada-containing polymer-coated surfaces to direct noncovalent conjugation of streptavidin, concanavalin A (ConA), and fibroblast cells, respectively. It was demonstrated that the mannose-functionalized coating could selectively bind to the target lectin ConA, and the interface could be regenerated and reused several times. Moreover, the polymeric coating was adaptable for cell attachment and proliferation upon noncovalent modification with cell-adhesive peptides. One can envision that the facile synthesis of the Ada-based copolymers, mild conditions for coating surfaces, and their effective transformation to various functional interfaces in a modular fashion offers an attractive approach to engineering functional interfaces for several biomedical applications.
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- 2023
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120. Biotechnological interventions and production of galanthamine in Crinum spp.
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Sanyal R, M M, Pandey S, Nandi S, Biswas P, Dewanjee S, Gopalakrishnan AV, Jha NK, Jha SK, Joshee N, Pandey DK, Dey A, and Shekhawat MS
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- Plant Extracts pharmacology, Galantamine, Phytochemicals, Crinum chemistry, Alkaloids chemistry
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Genus Crinum L. is a member of the Amaryllidaceae family having beautiful, huge, ornamental plants with umbels of lily-like blooms that are found in tropical and subtropical climates all over the world. For thousands of years, Crinum has been used as a traditional medicine to treat illnesses and disorders. Numerous distinct alkaloids of the Amaryllidaceae group, whose most well-known properties include analgesic, anticholinergic, antitumor, and antiviral, have recently been discovered by phytochemical analyses. However, because of decades of overexploitation for their economically significant bioactive ingredients and poor seed viability and germination rates, these plants are now threatened in their native environments. Because of these factors, researchers are investigating micropropagation techniques to optimize phytochemicals in vitro. This review's objective is to offer details on the distribution, phytochemistry, micropropagation, in vitro galanthamine synthesis, and pharmacology which will help to design biotechnological techniques for the preservation, widespread multiplication, and required secondary metabolite production from Crinum spp. KEY POINTS: • Botanical description and phytochemical profile of Crinum spp. • In vitro micropropagation method of Crinum sp. • Bioactive compound galanthamine isolation techniques and its pharmacological properties., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2023
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121. Optimizing raffinose family oligosaccharides content in plants: A tightrope walk.
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Sanyal R, Kumar S, Pattanayak A, Kar A, and Bishi SK
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Plants synthesize various compounds for their growth, metabolism, and stress mitigation, and one such group of compounds is the raffinose family of oligosaccharides (RFOs). RFOs are non-reducing oligosaccharides having galactose residues attached to a sucrose moiety. They act as carbohydrate reserves in plants, assisting in seed germination, desiccation tolerance, and biotic/abiotic stress tolerance. Although legumes are among the richest sources of dietary proteins, the direct consumption of legumes is hindered by an excess of RFOs in the edible parts of the plant, which causes flatulence in humans and monogastric animals. These opposing characteristics make RFOs manipulation a complicated tradeoff. An in-depth knowledge of the chemical composition, distribution pattern, tissue mobilization, and metabolism is required to optimize the levels of RFOs. The most recent developments in our understanding of RFOs distribution, physiological function, genetic regulation of their biosynthesis, transport, and degradation in food crops have been covered in this review. Additionally, we have suggested a few strategies that can sustainably reduce RFOs in order to solve the flatulence issue in animals. The comprehensive information in this review can be a tool for researchers to precisely control the level of RFOs in crops and create low antinutrient, nutritious food with wider consumer acceptability., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Sanyal, Kumar, Pattanayak, Kar and Bishi.)
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- 2023
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122. pH-Responsive nanofiber buttresses as local drug delivery devices.
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Altinbasak I, Kocak S, Colby AH, Alp Y, Sanyal R, Grinstaff MW, and Sanyal A
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- Humans, Drug Delivery Systems, Polymers chemistry, Doxorubicin pharmacology, Hydrogen-Ion Concentration, Drug Liberation, Nanofibers chemistry, Neoplasms
- Abstract
Electrospun nanofibers are a 3D scaffold of choice for many drug delivery devices due to their high surface area, significant capacity for drug payload, ease of in situ placement, and scalable manufacture. Herein, we report the synthesis of polymeric, pH-responsive nanofiber buttresses via electrospinning. The homopolymer is comprised of an acrylic backbone with acid-sensitive, hydrolyzable, trimethoxybenzaldehyde-protected side chains that lead to buttress transformation from a hydrophobic to a hydrophilic state under physiologically relevant pH conditions ( e.g. , extracellular tumor environment with pH = 6.5). Hydrolysis of the side chains leads to an increase in fiber diameter from approximately 350 to 900 nm and the release of the encapsulated drug cargo. In vitro drug release profiles demonstrate that significantly more drug is released at pH 5.5 compared to pH 7.4, thereby limiting the release to the target site, with docetaxel releasing over 20 days and doxorubicin over 7 days. Drug burst release, defined as >50% within 24 hours, does not occur at either pH or with either drug. Drug-loaded buttresses preserve drug activity and are cytotoxic to multiple human cancer lines, including breast and lung. Important to their potential application in surgical applications, the tensile strength of the buttresses is 6.3 kPa and, though weaker than commercially available buttresses, they provide sufficient flexibility and mechanical integrity to serve as buttressing materials via the application with a conventional surgical cutting stapler.
- Published
- 2023
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123. Spatio-temporal expression pattern of Raffinose Synthase genes determine the levels of Raffinose Family Oligosaccharides in peanut (Arachis hypogaea L.) seed.
- Author
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Sanyal R, Pradhan B, Jawed DM, Tribhuvan KU, Dahuja A, Kumar M, Kumar N, Mishra GP, Ram C, Mahatma MK, Singh BK, Mangrauthia SK, Singh AK, Sharma TR, Pattanayak A, and Bishi SK
- Subjects
- Raffinose metabolism, Oligosaccharides metabolism, Seeds metabolism, Arachis genetics, Arachis metabolism, Plant Breeding
- Abstract
Raffinose family oligosaccharides (RFOs) are known to have important physiological functions in plants. However, the presence of RFOs in legumes causes flatulence, hence are considered antinutrients. To reduce the RFOs content to a desirable limit without compromising normal plant development and functioning, the identification of important regulatory genes associated with the biosynthetic pathway is a prerequisite. In the present study, through comparative RNA sequencing in contrasting genotypes for seed RFOs content at different seed maturity stages, differentially expressed genes (DEGs) associated with the pathway were identified. The DEGs exhibited spatio-temporal expression patterns with high RFOs variety showing early induction of RFOs biosynthetic genes and low RFOs variety showing a late expression at seed maturity. Selective and seed-specific differential expression of raffinose synthase genes (AhRS14 and AhRS6) suggested their regulatory role in RFOs accumulation in peanut seeds, thereby serving as promising targets in low RFOs peanut breeding programs. Despite stachyose being the major seed RFOs fraction, differential expression of raffinose synthase genes indicated the complex metabolic regulation of this pathway. The transcriptomic resource and the genes identified in this study could be studied further to develop low RFOs varieties, thus improving the overall nutritional quality of peanuts., (© 2023. The Author(s).)
- Published
- 2023
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124. Tropical Carathéodory with Matroids.
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Loho G and Sanyal R
- Abstract
Bárány's colorful generalization of Carathéodory's Theorem combines geometrical and combinatorial constraints. Kalai-Meshulam (2005) and Holmsen (2016) generalized Bárány's theorem by replacing color classes with matroid constraints. In this note, we obtain corresponding results in tropical convexity, generalizing the Tropical Colorful Carathéodory Theorem of Gaubert-Meunier (2010). Our proof is inspired by geometric arguments and is reminiscent of matroid intersection. Moreover, we show that the topological approach fails in this setting. We also discuss tropical colorful linear programming and show that it is NP-complete. We end with thoughts and questions on generalizations to polymatroids, anti-matroids as well as examples and matroid simplicial depth., (© The Author(s) 2022.)
- Published
- 2023
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125. Protein Modification Employing Non-Canonical Amino Acids to Prepare SUMOylation Detecting Bioconjugates.
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Williard AC, Switzer HJ, Howard CA, Yin R, Russell BL, Sanyal R, Yu S, Myers TM, Flood BM, Kerscher O, and Young DD
- Abstract
Protein modification with non-canonical amino acids (ncAAs) represents a useful technology to afford homogenous samples of bioconjugates with site-specific modification. This technique can be directly applied to the detection of aberrant SUMOylation patterns, which are often indicative of disease states. Modified SUMO-trapping proteins, consisting of a catalytically inactive ULP1 fragment (UTAG) fused to the maltose-binding protein MBP, are useful reagents for the binding and labeling of SUMOylated proteins. Mutation of this UTAG fusion protein to facilitate amber suppression technologies for the genetic incorporation of ncAAs was assessed to provide a functional handle for modification. Ultimately, two sites in the maltose-binding protein (MBP) fusion were identified as ideal for incorporation and bioconjugation without perturbation to the SUMO-trapping ability of the UTAG protein. This functionality was then employed to label SUMOylated proteins in HeLa cells and demonstrate their enrichment in the nucleus. This modified UTAG-MBP-ncAA protein has far-reaching applications for both diagnostics and therapeutics.
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- 2022
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126. "Clickable" Polymer Brush Interfaces: Tailoring Monovalent to Multivalent Ligand Display for Protein Immobilization and Sensing.
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Degirmenci A, Yeter Bas G, Sanyal R, and Sanyal A
- Subjects
- Alkenes, Alkynes chemistry, Azides chemistry, Coloring Agents, Concanavalin A, Ligands, Maleimides, Mannose, Polyethylene Glycols chemistry, Silicon Dioxide, Sulfhydryl Compounds chemistry, Dendrimers, Polymers chemistry
- Abstract
Facile and effective functionalization of the interface of polymer-coated surfaces allows one to dictate the interaction of the underlying material with the chemical and biological analytes in its environment. Herein, we outline a modular approach that would enable installing a variety of "clickable" handles onto the surface of polymer brushes, enabling facile conjugation of various ligands to obtain functional interfaces. To this end, hydrophilic anti-biofouling poly(ethylene glycol)-based polymer brushes are fabricated on glass-like silicon oxide surfaces using reversible addition-fragmentation chain transfer (RAFT) polymerization. The dithioester group at the chain-end of the polymer brushes enabled the installation of azide, maleimide, and terminal alkene functional groups, using a post-polymerization radical exchange reaction with appropriately functionalized azo-containing molecules. Thus, modified polymer brushes underwent facile conjugation of alkyne or thiol-containing dyes and ligands using alkyne-azide cycloaddition, Michael addition, and radical thiol-ene conjugation, respectively. Moreover, we demonstrate that the radical exchange approach also enables the installation of multivalent motifs using dendritic azo-containing molecules. Terminal alkene groups containing dendrons amenable to functionalization with thiol-containing molecules using the radical thiol-ene reaction were installed at the interface and subsequently functionalized with mannose ligands to enable sensing of the Concanavalin A lectin.
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- 2022
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127. Fast-Forming Dissolvable Redox-Responsive Hydrogels: Exploiting the Orthogonality of Thiol-Maleimide and Thiol-Disulfide Exchange Chemistry.
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Altinbasak I, Kocak S, Sanyal R, and Sanyal A
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- Disulfides chemistry, Dithiothreitol, Maleimides chemistry, Oxidation-Reduction, Polyethylene Glycols chemistry, Polymers chemistry, Hydrogels chemistry, Sulfhydryl Compounds chemistry
- Abstract
Fast-forming yet easily dissolvable hydrogels (HGs) have potential applications in wound healing, burn incidences, and delivery of therapeutic agents. Herein, a combination of a thiol-maleimide conjugation and thiol-disulfide exchange reaction is employed to fabricate fast-forming HGs which rapidly dissolve upon exposure to dithiothreitol (DTT), a nontoxic thiol-containing hydrophilic molecule. In particular, maleimide disulfide-terminated telechelic linear poly(ethylene glycol) (PEG) polymer and PEG-based tetrathiol macromonomers are employed as gel precursors, which upon mixing yield HGs within a minute. The selectivity of the thiol-maleimide conjugation in the presence of a disulfide linkage was established through
1 H NMR spectroscopy and Ellman's test. Rapid degradation of HGs in the presence of thiol-containing solution was evident from the reduction in storage modulus. HGs encapsulated with fluorescent dye-labeled dextran polymers and bovine serum albumin were fabricated, and their cargo release was investigated under passive and active conditions upon exposure to DTT. One can envision that the rapid gelation and fast on-demand dissolution under relatively benign conditions would make these polymeric materials attractive for a range of biomedical applications.- Published
- 2022
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128. Molecularly Imprinted Polymer-Coated Inorganic Nanoparticles: Fabrication and Biomedical Applications.
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Orbay S, Kocaturk O, Sanyal R, and Sanyal A
- Abstract
Molecularly imprinted polymers (MIPs) continue to gain increasing attention as functional materials due to their unique characteristics such as higher stability, simple preparation, robustness, better binding capacity, and low cost. In particular, MIP-coated inorganic nanoparticles have emerged as a promising platform for various biomedical applications ranging from drug delivery to bioimaging. The integration of MIPs with inorganic nanomaterials such as silica (SiO
2 ), iron oxide (Fe3 O4 ), gold (Au), silver (Ag), and quantum dots (QDs) combines several attributes from both components to yield highly multifunctional materials. These materials with a multicomponent hierarchical structure composed of an inorganic core and an imprinted polymer shell exhibit enhanced properties and new functionalities. This review aims to provide a general overview of key recent advances in the fabrication of MIPs-coated inorganic nanoparticles and highlight their biomedical applications, including drug delivery, biosensor, bioimaging, and bioseparation.- Published
- 2022
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129. In vitro propagation and secondary metabolite production in Gloriosa superba L.
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Sanyal R, Nandi S, Pandey S, Das T, Kaur P, Konjengbam M, Kant N, Rahman MH, Mundhra A, Kher MM, Anand U, Radha, Kumar M, Jha NK, Jha SK, Shekhawat MS, Pandey DK, and Dey A
- Subjects
- Colchicine, Seeds, Plants, Medicinal, Colchicaceae
- Abstract
Gloriosa superba L., commonly known as "gloriosa lily," "glory lily," and "tiger claw," is a perennial climber in the Liliaceae family. This plant is used in African and Southeast Asian cultures as an ayurvedic medicinal herb to treat various health conditions. Its main bioactive component is colchicine, which is responsible for medicinal efficacies as well as poisonous properties of the plant. A high market demand, imprudent harvesting of G. superba from natural habitat, and low seed setting have led scientists to explore micropropagation techniques and in vitro optimization of its phytochemicals. Plant growth regulators have been used to induce callus, root, and shoot organogenesis, and somatic embryogenesis in vitro. This review is aimed at presenting information regarding the occurrence, taxonomic description, phytochemistry, micropropagation, in vitro secondary metabolite, and synthetic seed production. The data collected from the existing literature, along with an analysis of individual study details, outcomes, and variations in the reports, will contribute to the development of biotechnological strategies for conservation and mass propagation of G. superba. KEY POINTS: • Latest literature on micropropagation of Gloriosa superba. • Biotechnological production and optimization of colchicine. • Regeneration, somatic embryogenesis, and synthetic seed production., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2022
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130. Non-small cell lung carcinoma (NSCLC): Implications on molecular pathology and advances in early diagnostics and therapeutics.
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Padinharayil H, Varghese J, John MC, Rajanikant GK, Wilson CM, Al-Yozbaki M, Renu K, Dewanjee S, Sanyal R, Dey A, Mukherjee AG, Wanjari UR, Gopalakrishnan AV, and George A
- Abstract
Continuous revision of the histologic and stage-wise classification of lung cancer by the World Health Organization (WHO) provides the foundation for therapeutic advances by promoting molecular targeted and immunotherapies and ensuring accurate diagnosis. Cancer epidemiologic data provide helpful information for cancer prevention, diagnosis, and management, supporting health-care interventions. Global cancer mortality projections from 2016 to 2060 show that cancer will overtake ischemic heart diseases (IHD) as the leading cause of death (18.9 million) immediately after 2030, surpassing non-small cell lung cancer (NSCLC), which accounts for 85 percent of lung cancers. The clinical stage at the diagnosis is the main prognostic factor in NSCLC therapies. Advanced early diagnostic methods are essential as the initial stages of cancer show reduced mortality compared to the advanced stages. Sophisticated approaches to proper histological classification and NSCLC management have improved clinical efficiency. Although immune checkpoint inhibitors (ICIs) and targeted molecular therapies have refined the therapeutic management of late-stage NSCLC, the specificity and sensitivity of cancer biomarkers should be improved by focusing on prospective studies, followed by their use as therapeutic tools. The liquid biopsy candidates such as circulating tumor cells (CTCs), circulating cell-free tumor DNA (cfDNA), tumor educated platelets (TEP), and extracellular vesicles (EVs) possess cancer-derived biomolecules and aid in tracing: driver mutations leading to cancer, acquired resistance caused by various generations of therapeutic agents, refractory disease, prognosis, and surveillance., Competing Interests: The authors declare that there are no conflict of interests., (© 2022 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.)
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- 2022
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131. Carcinoma Type Classification From High-Resolution Breast Microscopy Images Using a Hybrid Ensemble of Deep Convolutional Features and Gradient Boosting Trees Classifiers.
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Sanyal R, Kar D, and Sarkar R
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- Female, Humans, Image Processing, Computer-Assisted methods, Microscopy, Neural Networks, Computer, Breast Neoplasms diagnostic imaging, Breast Neoplasms pathology, Carcinoma
- Abstract
Breast cancer is one of the main causes behind cancer deaths in women worldwide. Yet, owing to the complexity of the histopathological images and the arduousness of manual analysis task, the entire diagnosis process becomes time-consuming and the results are often contingent on the pathologist's subjectivity. Thus developing an automated, precise histopathological image classification system is crucial. This paper presents a novel hybrid ensemble framework consisting of multiple fine-tuned convolutional neural network (CNN) architectures as supervised feature extractors and eXtreme gradient boosting trees (XGBoost) as a top-level classifier, for patch wise classification of high-resolution breast histopathology images. Due to the semantic complexity of the patch images, a single CNN architecture may not always extract high quality features, and the traditional Softmax classifier might not provide ideal results for classifying the CNN extracted features. Thus we aim to improve patch wise classification by proposing a hybrid ensemble model that incorporates different discriminating feature representations of the patches, coupled with XGBoost for robust classification. Experimental results show that our proposed method outperforms state-of-the-art methods to the best of our knowledge.
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- 2022
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132. Focal Nodular Hyperplasia and Focal Nodular Hyperplasia-like Lesions.
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LeGout JD, Bolan CW, Bowman AW, Caserta MP, Chen FK, Cox KL, Sanyal R, Toskich BB, Lewis JT, and Alexander LF
- Subjects
- Diagnosis, Differential, Female, Humans, Hyperplasia complications, Hyperplasia pathology, Liver blood supply, Magnetic Resonance Imaging methods, Portal Vein, Focal Nodular Hyperplasia complications, Focal Nodular Hyperplasia diagnostic imaging, Liver Neoplasms diagnostic imaging
- Abstract
Focal nodular hyperplasia (FNH) is a benign lesion occurring in a background of normal liver. FNH is seen most commonly in young women and can often be accurately diagnosed at imaging, including CT, MRI, or contrast-enhanced US. In the normal liver, FNH frequently must be differentiated from hepatocellular adenoma, which although benign, is managed differently because of the risks of hemorrhage and malignant transformation. When lesions that are histologically identical to FNH occur in a background of abnormal liver, they are termed FNH-like lesions. These lesions can be a source of diagnostic confusion and must be differentiated from malignancies. Radiologists' familiarity with the imaging appearance of FNH-like lesions and knowledge of the conditions that predispose a patient to their formation are critical to minimizing the risks of unnecessary intervention for these lesions, which are rarely symptomatic and carry no risk for malignant transformation. FNH is thought to form secondary to an underlying vascular disturbance, a theory supported by the predilection for formation of FNH-like lesions in patients with a variety of hepatic vascular abnormalities. These include abnormalities of hepatic outflow such as Budd-Chiari syndrome, abnormalities of hepatic inflow such as congenital absence of the portal vein, and hepatic microvascular disturbances, such as those that occur after exposure to certain chemotherapeutic agents. Familiarity with the imaging appearances of these varied conditions and knowledge of their association with formation of FNH-like lesions allow radiologists to identify with confidence these benign lesions that require no intervention. Online supplemental material is available for this article.
© RSNA, 2022.- Published
- 2022
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133. Redox-Responsive Hydrogels for Tunable and "On-Demand" Release of Biomacromolecules.
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Kilic Boz R, Aydin D, Kocak S, Golba B, Sanyal R, and Sanyal A
- Subjects
- Disulfides chemistry, Dithiothreitol, Oxidation-Reduction, Sulfhydryl Compounds chemistry, Hydrogels chemistry, Polyethylene Glycols chemistry
- Abstract
In recent years, stimuli-responsive degradation has emerged as a desirable design criterion for functional hydrogels to tune the release of encapsulated payload as well as ensure degradation of the gel upon completion of its function. Herein, redox-responsive hydrogels with a well-defined network structure were obtained using a highly efficient thiol-disulfide exchange reaction. In particular, gelation occurred upon combining thiol-terminated tetra-arm polyethylene glycol (PEG) polymers with linear telechelic PEG-based polymers containing pyridyl disulfide units at their chain ends. Rapid gelation proceeds with good conversions (>85%) to yield macroporous hydrogels possessing high water uptake. Furthermore, due to the presence of the disulfide linkages, the thus-obtained hydrogels can self-heal. The obtained hydrogels undergo complete degradation when exposed to environments rich in thiol-containing agents such as dithiothreitol (DTT) and L-glutathione (GSH). Also, the release profile of encapsulated protein, namely, bovine serum albumin, can be tuned by varying the molecular weight of the polymeric precursors. Additionally, it was demonstrated that complete dissolution of the hydrogel to rapidly release the encapsulated protein occurs upon treating these hydrogels with DTT. Cytotoxicity evaluation of the hydrogels and their degradation products indicated the benign nature of these hydrogels. Additionally, the cytocompatible nature of these materials was also evident from a live/dead cell viability assay. One can envision that the facile fabrication and their ability to degrade on-demand and release their payload will make these benign polymeric scaffolds attractive for various biomedical applications.
- Published
- 2022
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134. Cancer chemotherapy and beyond: Current status, drug candidates, associated risks and progress in targeted therapeutics.
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Anand U, Dey A, Chandel AKS, Sanyal R, Mishra A, Pandey DK, De Falco V, Upadhyay A, Kandimalla R, Chaudhary A, Dhanjal JK, Dewanjee S, Vallamkondu J, and Pérez de la Lastra JM
- Abstract
Cancer is an abnormal state of cells where they undergo uncontrolled proliferation and produce aggressive malignancies that causes millions of deaths every year. With the new understanding of the molecular mechanism(s) of disease progression, our knowledge about the disease is snowballing, leading to the evolution of many new therapeutic regimes and their successive trials. In the past few decades, various combinations of therapies have been proposed and are presently employed in the treatment of diverse cancers. Targeted drug therapy, immunotherapy, and personalized medicines are now largely being employed, which were not common a few years back. The field of cancer discoveries and therapeutics are evolving fast as cancer type-specific biomarkers are progressively being identified and several types of cancers are nowadays undergoing systematic therapies, extending patients' disease-free survival thereafter. Although growing evidence shows that a systematic and targeted approach could be the future of cancer medicine, chemotherapy remains a largely opted therapeutic option despite its known side effects on the patient's physical and psychological health. Chemotherapeutic agents/pharmaceuticals served a great purpose over the past few decades and have remained the frontline choice for advanced-stage malignancies where surgery and/or radiation therapy cannot be prescribed due to specific reasons. The present report succinctly reviews the existing and contemporary advancements in chemotherapy and assesses the status of the enrolled drugs/pharmaceuticals; it also comprehensively discusses the emerging role of specific/targeted therapeutic strategies that are presently being employed to achieve better clinical success/survival rate in cancer patients., (© 2022 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.)
- Published
- 2022
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135. Biotechnology for propagation and secondary metabolite production in Bacopa monnieri.
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Sanyal R, Nandi S, Pandey S, Chatterjee U, Mishra T, Datta S, Prasanth DA, Anand U, Mane AB, Kant N, Jha NK, Jha SK, Shekhawat MS, Pandey DK, and Dey A
- Subjects
- Agrobacterium genetics, Biotechnology, Plant Extracts metabolism, Plant Extracts pharmacology, Bacopa chemistry, Bacopa metabolism, Saponins metabolism, Triterpenes metabolism
- Abstract
Bacopa monnieri (L.) Wettst. or water hyssop commonly known as "Brahmi" is a small, creeping, succulent herb from the Plantaginaceae family. It is popularly employed in Ayurvedic medicine as a nerve tonic to improve memory and cognition. Of late, this plant has been reported extensively for its pharmacologically active phyto-constituents. The main phytochemicals are brahmine, alkaloids, herpestine, and saponins. The saponins include bacoside A, bacoside B, and betulic acid. Investigation into the pharmacological effect of this plant has thrived lately, encouraging its neuroprotective and memory supporting capacity among others. Besides, it possesses many other therapeutic activities like antimicrobial, antioxidant, anti-inflammatory, gastroprotective properties, etc. Because of its multipurpose therapeutic potential, it is overexploited owing to the prioritization of natural remedies over conventional ones, which compels us to conserve them. B. monnieri is confronting the danger of extinction from its natural habitat as it is a major cultivated medico-botanical and seed propagation is restricted due to less seed availability and viability. The ever-increasing demand for the plant can be dealt with mass propagation through plant tissue culture strategy. Micropropagation utilizing axillary meristems as well as de novo organogenesis have been widely investigated in this plant which has also been explored for its conservation and production of different types of secondary metabolites. Diverse in vitro methods such as organogenesis, cell suspension, and callus cultures have been accounted for with the aim of production and/or enhancement of bacosides. Direct shoot-organogenesis was initiated in excised leaf and internodal explants without any exogenous plant growth regulator(s) (PGRs), and the induction rate was improved when exogenous cytokinins and other supplements were used. Moreover, biotechnological toolkits like Agrobacterium-mediated transformation and the use of mutagens have been reported. Besides, the molecular marker-based studies demonstrated the clonal fidelity among the natural and in vitro generated plantlets also elucidating the inherent diversity among the natural populations. Agrobacterium-mediated transformation system was mostly employed to optimize bacoside biosynthesis and heterologous expression of other genes. The present review aims at depicting the recent research outcomes of in vitro studies performed on B. monnieri which include root and shoot organogenesis, callus induction, somatic embryogenesis, production of secondary metabolites by in vitro propagation, acclimatization of the in vitro raised plantlets, genetic transformation, and molecular marker-based studies of clonal fidelity. KEY POINTS: • Critical and up to date records on in vitro propagation of Bacopa monnieri • In vitro propagation and elicitation of secondary metabolites from B. monnieri • Molecular markers and transgenic studies in B. monnieri., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2022
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136. The use of hypnotherapy as treatment for functional stroke: A case series from a single center in the UK.
- Author
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Sanyal R, Raseta M, Natarajan I, and Roffe C
- Subjects
- Adult, Female, Humans, Prospective Studies, Research Design, Treatment Outcome, United Kingdom, Hypnosis methods, Stroke drug therapy
- Abstract
Background: Functional neurological disorder is defined by symptoms not explained by the current model of disease and its pathophysiology. It is found in 8.4% of patients presenting as acute stroke. Treatment is difficult and recurrence rates are high. We introduced hypnotherapy as a therapeutic option in addition to standard stroke unit care., Methods: This is an observational study of successive patients with functional neurological disorder presenting as acute stroke treated with hypnotherapy between 1 April 2014 and 1 February 2018. The diagnosis of functional neurological disorder was confirmed by clinical examination and computed tomography/magnetic resonance imaging. Hypnosis was delivered by a hypnotherapy trained stroke physician using imagery for induction. A positive response was defined as a National Institutes of Health Stroke score reduction to 0 or by ≥4 points posthypnotherapy. Costs were calculated as therapist time and benefits as reduction in disability/bed days., Results: Sixty-eight patients (mean age 36.4 years, 52 (76%) females, mean baseline National Institutes of Health Stroke 5.0 (range 1-9)) were included. Two patients (3%) could not be hypnotized. Fifty-eight 58 (85%) responded, 47 (81%) required one treatment session, while 19% needed up to three sessions for symptomatic improvement. No adverse events were observed. Disability (modified Rankin Scale) reduced from a mean of 2.3 to 0.5 resulting in an average cost saving of £1,658 per patient. Most (n = 50, 86%) remained well without recurrence at six-month follow-up., Conclusions: In this case series, hypnotherapy was associated with rapid and sustained recovery of symptoms. A prospective randomized controlled study is required to confirm the findings and establish generalizability of the results.
- Published
- 2022
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137. Neoechinulins: Molecular, cellular, and functional attributes as promising therapeutics against cancer and other human diseases.
- Author
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Mitra S, Anand U, Sanyal R, Jha NK, Behl T, Mundhra A, Ghosh A, Radha, Kumar M, Proćków J, and Dey A
- Subjects
- Alkaloids chemistry, Alkaloids isolation & purification, Animals, Anti-Inflammatory Agents isolation & purification, Anti-Inflammatory Agents pharmacology, Antineoplastic Agents isolation & purification, Antineoplastic Agents pharmacology, Humans, Inflammation pathology, Mice, Neoplasms pathology, Neurodegenerative Diseases drug therapy, Neurodegenerative Diseases physiopathology, PC12 Cells, Piperazines chemistry, Piperazines isolation & purification, RAW 264.7 Cells, Rats, Alkaloids pharmacology, Inflammation drug therapy, Neoplasms drug therapy, Piperazines pharmacology
- Abstract
Neoechinulins are fungal and plant-derived chemicals extracted from Microsporum sp., Eurotium rubrum, Aspergillus sp., etc. Two analogues of neoechinulin, i.e., A and B, exerted extensive pharmacological properties described in this review. Neoechinulin is an indole alkaloid and has a double bond between C8/C9, which tends to contribute to its cytoprotective nature. Neoechinulin A exhibits protection to PC12 cells against nitrosative stress via increasing NAD(P)H reserve capacity and decreasing cellular GSH levels. It also confers protection via rescuing PC12 cells from rotenone-induced stress by lowering LDH leakage. This compound has great positive potential against neurodegenerative diseases by inhibiting SIN-1 induced cell death in neuronal cells. Together with these, neoechinulin A tends to inhibit Aβ42-induced microglial activation and confers protection against neuroinflammation. Alongside, it also inhibits cervical cancer cells by caspase-dependent apoptosis and via upregulation of apoptosis inducing genes like Bax, it suppresses LPS-induced inflammation in RAW264.7 macrophages and acts as an antidepressant. Whereas, another analogue, Neoechinulin B tends to interfere with the cellular mechanism thereby, inhibiting the entry of influenza A virus and it targets Liver X receptor (LXR) and decreases the infection rate of Hepatitis C. The present review describes the pharmaceutical properties of neoechinulins with notes on their molecular, cellular, and functional basis and their therapeutic properties., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
- Published
- 2022
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138. Biotechnological interventions and genetic diversity assessment in Swertia sp.: a myriad source of valuable secondary metabolites.
- Author
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Kaur P, Pandey DK, Gupta RC, Kumar V, Dwivedi P, Sanyal R, and Dey A
- Subjects
- Australia, Biotechnology, Genetic Variation, Plant Extracts, Swertia genetics
- Abstract
The genus Swertia (Family: Gentianaceae) has cosmopolitan distribution which is present in almost all the continents except South America and Australia. Swertia genus has been renowned as one of the potent herbal drugs in the British, American, and Chinese Pharmacopeias as well as well-documented in the Indian traditional medicinal systems, viz. Ayurveda, Siddha, and Unani. Many species of this genus have therapeutic properties and have been used traditionally in the treatment of a number of health ailments viz. hepatitis, diabetes, inflammation, bacillary dysentery, cancer, malaria, fever etc. This genus is industrially important medicinal plant that has been used as a principal component in numerous marketed herbal/ polyherbal formulations. Medicinal usage of Swertia is endorsed to the miscellaneous compounds viz. xanthones, irridoids, seco-irridoids, and triterpenoids. A chain of systematic isolation of bio-active compounds and their diverse range of pharmacological effects during last 15-20 years proved this genus as industrially important plant. Due to the various practices of the Swertia species, annual demand is more than 100 tons per year for this important herb which is continuously increasing 10% annually. The market value rises 10% by the year as there is increased demand in national and international market resulted in adulteration of many Swertia spp. due to paucity of agricultural practices, exomorphological, phytochemical, and molecular characterization. Thus, efficient biotechnology methods are prerequisite for the mass production of authentic species, sustainable production of bio-active compounds and ex situ conservation. A chain of systematic biotechnological interventions in Swertia herb during last 20 years cover the assessment of genetic diversity, in vitro sustainable production of bio-active compounds and mass propagation of elite genotypes via direct and indirect organogenesis. This review attempts to present the comprehensive assessment on biotechnological process made in Swertia over the past few years. KEY POINTS: • Critical and updated assessment on biotechnological aspects of Swertia spp. • In vitro propagation and genetic diversity assessment in Swertia spp. • Biosynthesis and sustainable production of secondary metabolites in Swertia spp.
- Published
- 2021
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139. Nephrogenic systemic fibrosis: A frivolous entity.
- Author
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Bhargava V, Singh K, Meena P, and Sanyal R
- Abstract
Gadolinium-based contrast agents (GBCAs) used in magnetic resonance imaging are vital in providing enhanced quality images, essential for diagnosis and treatment. Nephrogenic systemic fibrosis (NSF) with GBCAs has been a deterrent for the physician and has led to avoidance of these agents in patients with impaired kidney function. NSF is a progressive debilitating multisystem condition described classically in patients with renal insufficiency exposed to gadolinium contrast media. It is characterized by an induration and hardening of the skin. NSF is described to first involve the extremities and can imperceptibly involve internal organs. Lack of therapeutic interventions to treat NSF makes it more challenging and warrants deep insight into the pathogenesis, risk factors and treatment strategies., Competing Interests: Conflict-of-interest statement: There is no conflict of interest to disclose., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)
- Published
- 2021
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140. The Male Urethra: Imaging and Surgical Approach for Common Pathologies.
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Galgano SJ, Sivils C, Selph JP, Sanyal R, Lockhart ME, and Zarzour JG
- Subjects
- Humans, Male, Postoperative Complications diagnostic imaging, Diagnostic Imaging, Urethra diagnostic imaging, Urethra surgery
- Abstract
Urethral pathology is common in clinical practice and important to recognize. It is essential to recognize urethral pathology on imaging and to understand how to best image the urethra. In this way, the radiologist can provide the urologist with the necessary information prior to intervention. Basic knowledge of commonly performed urethral surgeries can help the radiologist understand the expected appearance of the post-treatment urethra and common postoperative complications., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2021
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141. Dermal delivery and follicular targeting of adapalene using PAMAM dendrimers.
- Author
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Gökçe BB, Boran T, Emlik Çalık F, Özhan G, Sanyal R, and Güngör S
- Subjects
- Adapalene, Drug Carriers metabolism, Skin metabolism, Skin Absorption, Dendrimers
- Abstract
Acne is a chronic dermatological disease of pilosebaceous units existing in the form of hair follicles (HFs) and accompanying sebaceous glands. In topical acne treatment, localisation of drug substance at the target site, in pilosebaceous units, especially in HFs is essential. The aims of this study were to develop and optimise adapalene (ADA)-loaded PAMAM dendrimer-based nanocarriers for topical acne treatment and to prepare gel formulations of the selected nanocarriers and to characterise their rheological properties and spreadability. ADA accumulation in HFs and in the skin from PAMAM dendrimers' aqueous colloidal formulations and their gel formulations were quantitatively determined using punch biopsy technique. Follicular targeting efficiency from PAMAM dendrimers and their gel formulation was compared with the commercial gel product, Differin
® Gel. The localisation of fluorescently labelled PAMAM dendrimers was visualised using a confocal microscope, which confirmed a successful delivery of the carrier system to the HFs. It was also quantified that PAMAM dendrimers improved follicular localisation and skin deposition of ADA. PAMAM dendrimers' gel formulation including lower ADA doses compared with the commercial product exhibited efficient performance in terms of drug accumulation in HFs. In vitro cell viability studies showed the relative safety of G2-PAMAM dendrimers which could be considered to possibly be well tolerated by the skin. Overall, PAMAM dendrimers' potential to selectively target drugs to the site of action, reduce dose administrated, therefore minimise side effects and provide efficiency in topical treatment of dermatological diseases such as acne was shown.- Published
- 2021
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142. Photothermally Active Cryogel Devices for Effective Release of Antimicrobial Peptides: On-Demand Treatment of Infections.
- Author
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Chambre L, Rosselle L, Barras A, Aydin D, Loczechin A, Gunbay S, Sanyal R, Skandrani N, Metzler-Nolte N, Bandow JE, Boukherroub R, Szunerits S, and Sanyal A
- Subjects
- Anti-Bacterial Agents chemistry, Antimicrobial Cationic Peptides chemistry, Cryogels chemical synthesis, Cryogels radiation effects, Cycloaddition Reaction, Drug Liberation, Escherichia coli drug effects, Furans chemical synthesis, Furans chemistry, Furans radiation effects, HeLa Cells, Heating, Humans, Infrared Rays, Methacrylates chemical synthesis, Methacrylates chemistry, Methacrylates radiation effects, Microbial Sensitivity Tests, Polyethylene Glycols chemical synthesis, Polyethylene Glycols chemistry, Polyethylene Glycols radiation effects, Staphylococcus aureus drug effects, Anti-Bacterial Agents pharmacology, Antimicrobial Cationic Peptides pharmacology, Cryogels chemistry, Staphylococcal Infections drug therapy
- Abstract
There has been significant interest in the use of peptides as antimicrobial agents, and peptide containing hydrogels have been proposed as biological scaffolds for various applications. Limited stability and rapid clearance of small molecular weight peptides pose challenges to their widespread implementation. As a common approach, antibacterial peptides are physically loaded into hydrogel scaffolds, which leads to continuous release through the passive mode with spatial control but provides limited control over drug dosage. Although utilization of peptide covalent linkage onto hydrogels addresses partially this problem, the peptide release is commonly too slow. To alleviate these challenges, in this work, maleimide-modified antimicrobial peptides are covalently conjugated onto furan-based cryogel (CG) scaffolds via the Diels-Alder cycloaddition at room temperature. The furan group offers a handle for specific loading of the peptides, thus minimizing passive and burst drug release. The porous nature of the CG matrix provides rapid loading and release of therapeutic peptides, apart from high water uptake. Interfacing the peptide adduct containing a CG matrix with a reduced graphene oxide-modified Kapton substrate allows "on-demand" photothermal heating upon near-infrared (NIR) irradiation. A fabricated photothermal device enables tunable and efficient peptide release through NIR exposure to kill bacteria. Apart from spatial confinement offered by this CG-based bandage, the selective ablation of planktonic Staphylococcus aureus is demonstrated. It can be envisioned that this modular "on-demand" peptide-releasing device can be also employed for other topical applications by appropriate choice of therapeutic peptides.
- Published
- 2020
- Full Text
- View/download PDF
143. Frontal fibrosing alopecia shows robust T helper 1 and Janus kinase 3 skewing.
- Author
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Del Duca E, Ruano Ruiz J, Pavel AB, Sanyal RD, Song T, Gay-Mimbrera J, Zhang N, Estrada YD, Peng X, Renert-Yuval Y, Phelps RG, Paus R, Krueger JG, and Guttman-Yassky E
- Subjects
- Alopecia, Humans, Janus Kinase 3, Quality of Life, Scalp, Alopecia Areata, Lichen Planus
- Abstract
Background: Frontal fibrosing alopecia (FFA) is a scarring alopecia with unclear pathogenesis and a progressive course. The disease has a major impact on patients' quality of life and there is a lack of effective treatment to halt disease progression., Methods: We profiled lesional and nonlesional scalp biopsies collected in 2017 from patients with FFA (n = 12) compared with scalp biopsies from patients with alopecia areata (AA) (n = 8) and controls (n = 8) to evaluate gene and protein expression, including the primary outcome (CXCL9). We determined significant differences between biomarkers using a two-sided Student's t-test adjusting P-values by false discovery rate., Results: Significant increases were seen in CD8+ cytotoxic T cells, CD11c+ dendritic cells, CD103+ and CD69+ tissue-resident memory T cells in FFA and AA vs. control scalp (P < 0·05), with corresponding significantly upregulated granzyme B mRNA, particularly in FFA (P < 0·01). In AA, cellular infiltrates were primarily concentrated at the bulb, while in FFA these were mainly localized at the bulge. FFA demonstrated significant upregulation of T helper 1/intereferon (IFN) (IFN-γ, CXCL9/CXCL10), the Janus kinase/signal transducers and activators of transcription (JAK-STAT) pathway (STAT1, JAK3) and fibrosis-related products (vimentin, fibronectin; P < 0·05), with no concomitant downregulation of hair keratins and the T-regulatory marker, forkhead box P3, which were decreased in AA. The stem cell markers CD200 and K15 demonstrated significantly reduced expression only in FFA (P < 0·05)., Conclusions: These data suggest that follicular damage and loss of stem cells in FFA may be mediated through immune attack in the bulge region, with secondary fibrosis and reduced but still detectable stem cells. JAK/STAT-targeting treatments may be able to prevent permanent follicular destruction and fibrosis in early disease stages., (© 2020 British Association of Dermatologists.)
- Published
- 2020
- Full Text
- View/download PDF
144. An 'on-demand' photothermal antibiotic release cryogel patch: evaluation of efficacy on an ex vivo model for skin wound infection.
- Author
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Rosselle L, Cantelmo AR, Barras A, Skandrani N, Pastore M, Aydin D, Chambre L, Sanyal R, Sanyal A, Boukherroub R, and Szunerits S
- Subjects
- Anti-Bacterial Agents, Humans, Skin, Staphylococcus aureus, Cryogels, Wound Infection
- Abstract
A myriad of topical therapies and dressings are available to the clinicians for wound healing skin, but only a very few have shown their effectiveness in promoting wound repair due to challenges in controlling drug release. To address this issue, in this work, a near infrared (NIR)-light activable cryogel based on butyl methacrylate (BuMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) incorporated with reduced graphene oxide (rGO) was fabricated. The obtained cryogel provides the required hydrophilicity beneficial for wound treatment. The excellent photo-thermal properties of rGO allow for heating the cryogel, which results in subsequent swelling of the cryogel (CG) followed by release of the encapsulated drug load, cefepime in our case. Without photothermal activation, no release of payload was observed. The potential of this bandage for wound healing was examined using an ex vivo human skin model infected with Staphylococcus aureus (S. aureus). Apart from the efficacy of the cryogel based wound healing system, our results also suggest that the ex vivo wound model evaluated here provides a rapid and valuable tool to study superficial skin infections in humans and test the efficacy of antimicrobial agents.
- Published
- 2020
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- View/download PDF
145. Studies on the Regulation of (p)ppGpp Metabolism and Its Perturbation Through the Over-Expression of Nudix Hydrolases in Escherichia coli .
- Author
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Sanyal R, Vimala A, and Harinarayanan R
- Abstract
Stringent response mediated by modified guanosine nucleotides is conserved across bacteria and is regulated through the Rel/Spo functions. In Escherichia coli , RelA and SpoT proteins synthesize the modified nucleotides ppGpp and pppGpp, together referred to as (p)ppGpp. SpoT is also the primary (p)ppGpp hydrolase. In this study, using hypomorphic relA alleles, we provide experimental evidence for SpoT-mediated negative regulation of the amplification of RelA-dependent stringent response. We investigated the kinetics of ppGpp degradation in cells recovering from stringent response in the complete absence of SpoT function. We found that, although greatly diminished, there was slow ppGpp degradation and growth resumption after a lag period, concomitant with decrease in ppGpp pool. We present evidence for reduction in the ppGpp degradation rate following an increase in pppGpp pool, during recovery from stringent response. From a genetic screen, the nudix hydrolases MutT and NudG were identified as over-expression suppressors of the growth defect of Δ spoT and Δ spoT Δ gppA strains. The effect of over-expression of these hydrolases on the stringent response to amino acid starvation and basal (p)ppGpp pool was studied. Over-expression of each hydrolase reduced the strength of the stringent response to amino acid starvation, and additionally, perturbed the ratio of ppGpp to pppGpp in strains with reduced SpoT hydrolase activity. In these strains that do not accumulate pppGpp during amino acid starvation, the expression of NudG or MutT supported pppGpp accumulation. This lends support to the idea that a reduction in the SpoT hydrolase activity is sufficient to cause the loss of pppGpp accumulation and therefore the phenomenon is independent of hydrolases that target pppGpp, such as GppA., (Copyright © 2020 Sanyal, Vimala and Harinarayanan.)
- Published
- 2020
- Full Text
- View/download PDF
146. Serial changes in renal allograft resistive index.
- Author
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Chen FK and Sanyal R
- Subjects
- Allografts, Graft Rejection, Humans, Kidney, Kidney Transplantation
- Published
- 2020
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- View/download PDF
147. Thiol-Reactive Clickable Cryogels: Importance of Macroporosity and Linkers on Biomolecular Immobilization.
- Author
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Chambre L, Maouati H, Oz Y, Sanyal R, and Sanyal A
- Subjects
- Animals, Cattle, Click Chemistry, Cryogels chemical synthesis, Cycloaddition Reaction, Maleimides chemical synthesis, Maleimides chemistry, Methacrylates chemical synthesis, Polyethylene Glycols chemical synthesis, Porosity, Smart Materials chemical synthesis, Cryogels chemistry, Immobilized Proteins chemistry, Methacrylates chemistry, Polyethylene Glycols chemistry, Serum Albumin, Bovine chemistry, Smart Materials chemistry, Sulfhydryl Compounds chemistry
- Abstract
Macroporous cryogels that are amenable to facile functionalization are attractive platforms for biomolecular immobilization, a vital step for fabrication of scaffolds necessary for areas like tissue engineering and diagnostic sensing. In this work, thiol-reactive porous cryogels are obtained via photopolymerization of a furan-protected maleimide-containing poly(ethylene glycol) (PEG)-based methacrylate (PEGFuMaMA) monomer. A series of cryogels are prepared using varying amounts of the masked hydrophilic PEGFuMaMA monomer, along with poly(ethylene glycol) methyl ether methacrylate and poly(ethylene glycol) dimethacrylate, a hydrophilic monomer and cross-linker, respectively, in the presence of a photoinitiator. Subsequent activation to the thiol-reactive form of the furan-protected maleimide groups is performed through the retro Diels-Alder reaction. As a demonstration of direct protein immobilization, bovine serum albumin is immobilized onto the cryogels. Furthermore, ligand-directed immobilization of proteins is achieved by first attaching mannose- or biotin-thiol onto the maleimide-containing platforms, followed by ligand-directed immobilization of concanavalin A or streptavidin, respectively. Additionally, we demonstrate that the extent of immobilized proteins can be controlled by varying the amount of thiol-reactive maleimide groups present in the cryogel matrix. Compared to traditional hydrogels, cryogels demonstrate enhanced protein immobilization/detection. Additionally, it is concluded that utilization of a longer linker, distancing the thiol-reactive maleimide group from the gel scaffold, considerably increases protein immobilization. It can be envisioned that the facile fabrication, conjugation, and control over the extent of functionalization of these cryogels will make these materials desirable scaffolds for numerous biomedical applications.
- Published
- 2020
- Full Text
- View/download PDF
148. Multifunctional and Transformable 'Clickable' Hydrogel Coatings on Titanium Surfaces: From Protein Immobilization to Cellular Attachment.
- Author
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Gevrek TN, Degirmenci A, Sanyal R, and Sanyal A
- Abstract
Multifunctionalizable hydrogel coatings on titanium interfaces are useful in a wide range of biomedical applications utilizing titanium-based materials. In this study, furan-protected maleimide groups containing multi-clickable biocompatible hydrogel layers are fabricated on a titanium surface. Upon thermal treatment, the masked maleimide groups within the hydrogel are converted to thiol-reactive maleimide groups. The thiol-reactive maleimide group allows facile functionalization of these hydrogels through the thiol-maleimide nucleophilic addition and Diels-Alder cycloaddition reactions, under mild conditions. Additionally, the strained alkene unit in the furan-protected maleimide moiety undergoes radical thiol-ene reaction, as well as the inverse-electron-demand Diels-Alder reaction with tetrazine containing molecules. Taking advantage of photo-initiated thiol-ene 'click' reactions, we demonstrate spatially controlled immobilization of the fluorescent dye thiol-containing boron dipyrromethene (BODIPY-SH). Lastly, we establish that the extent of functionalization on hydrogels can be controlled by attachment of biotin-benzyl-tetrazine, followed by immobilization of TRITC-labelled ExtrAvidin. Being versatile and practical, we believe that the described multifunctional and transformable 'clickable' hydrogels on titanium-based substrates described here can find applications in areas involving modification of the interface with bioactive entities., Competing Interests: The authors declare no conflict of interest.
- Published
- 2020
- Full Text
- View/download PDF
149. Fabrication of Patterned Hydrogel Interfaces: Exploiting the Maleimide Group as a Dual Purpose Handle for Cross-Linking and Bioconjugation.
- Author
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Cengiz N, Gevrek TN, Sanyal R, and Sanyal A
- Subjects
- Cycloaddition Reaction, Fluorescent Dyes chemistry, Photochemical Processes, Polymers chemistry, Sulfhydryl Compounds chemistry, Water chemistry, Hydrogels chemistry, Maleimides chemistry
- Abstract
Functional hydrogels that can be obtained through facile fabrication procedures and subsequently modified using straightforward reagent-free methods are indispensable materials for biomedical applications such as sensing and diagnostics. Herein a novel hydrogel platform is obtained using polymeric precursors containing the maleimide functional group as a side chain. The maleimide groups play a dual role in fabrication of functional hydrogels. They enable photochemical cross-linking of the polymers to yield bulk and patterned hydrogels. Moreover, the maleimide group can be used as a handle for efficient functionalization using the thiol-maleimide conjugation and Diels-Alder cycloaddition click reactions. Obtained hydrogels are characterized in terms of their morphology, water uptake capacity, and functionalization. Micropatterned hydrogels are obtained under UV-irradiation using a photomask to obtain reactive micropatterns, which undergo facile functionalization upon treatment with thiol-containing functional molecules such as fluorescent dyes and bioactive ligands. The maleimide group also undergoes conjugation through the Diels-Alder reaction, where the attached molecule can be released through thermal treatment via the retro Diels-Alder reaction. The antibiofouling nature of these hydrogel micropatterns enables efficient ligand-directed biomolecular immobilization, as demonstrated by attachment of streptavidin-coated quantum dots.
- Published
- 2020
- Full Text
- View/download PDF
150. Trastuzumab targeted micellar delivery of docetaxel using dendron-polymer conjugates.
- Author
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Sumer Bolu B, Golba B, Sanyal A, and Sanyal R
- Subjects
- Antineoplastic Agents chemistry, Cell Line, Tumor, Cell Survival drug effects, Dendrimers chemistry, Docetaxel chemistry, Drug Liberation, Humans, Trastuzumab chemistry, Antineoplastic Agents administration & dosage, Dendrimers administration & dosage, Docetaxel administration & dosage, Drug Delivery Systems, Micelles, Trastuzumab administration & dosage
- Abstract
Incorporation of a therapeutic antibody into nanosized drug delivery systems can improve their target specificity. This work reports an antibody-conjugated targeted delivery system composed of polymer-dendron conjugates. Trastuzumab is chosen as the targeting moiety, since it is clinically used against tumor cells expressing HER2 receptors. A micellar delivery system was generated using amphiphilic polymer-dendron conjugates containing a fourth-generation polyester dendron as the hydrophobic block and a linear poly(ethylene glycol) (PEG) chain as the hydrophilic block. After preparation of docetaxel loaded (ca. 10% wt) micelles, trastuzumab was conjugated onto the micellar shell using an amidation reaction. Micelles remained stable after conjugation of the antibody, with a slight increase in size from 179 nm to 185 nm upon functionalization. Docetaxel release was determined to be responsive to acidic pH, and over the course of 30 h, 54% drug release was measured in acidic media, whereas it was around 30% under neutral conditions. Cytotoxicity experiments on MCF-7 and SK-OV-3 cell lines displayed improved toxicity levels for targeted micelles in comparison with the non-targeted counterparts, whereas pulse-chase experiments indicated effectiveness of micellar formulations and the presence of targeting groups. Cellular internalization experiments using fluorescence microscopy and flow cytometry further demonstrated the enhanced cellular uptake of antibody conjugated targeted micelles.
- Published
- 2020
- Full Text
- View/download PDF
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