Browsing by Author "Saha S."
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Item Advancing Precision in Penile Length Measurement: Evidence-based Synthesis of Stretched Penile Length INdicator Technique (SPLINT)(Wolters Kluwer Medknow Publications, 2024) Goel P.; Choudhury P.; Saroya K.K.; Jain V.; Dhua A.K.; Yadav D.K.; Anand S.; Agarwala S.; Sharma K.; Agrawal V.; Saha S.; Singh H.; Sharma N.; Singh V.P.Purpose: The purpose of this study was to synthesize evidence and propose a technique for estimation of stretched penile length (SPL) applicable to children. Materials and Methods: This review has been conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. PubMed, Embase, and Scopus databases were queried on penile length (PL) measurement techniques in humans published from 1990 onward. The devices and the techniques used for PL measurement, state of the penis, the habitus of the participants, proximal and distal landmarks for measurement, handling the foreskin and pubic pad of fat, optimal stretching of the penis, and other factors (including the environment) which should be accounted for in the technique were identified from the study cohort (90895 participants across 145 included studies). Results: PL has been represented through flaccid (33.79%), stretched (81.3%), and erect (12.41%) PLs as well as the greatest corporeal length (1.4%). Following devices have been used to measure the PL in the study cohort: rulers [54.68%], calipers [9.7%], measuring tapes [14.5%], coloured measuring strips [2.06%], spatulas/tongue depressors [11.03%], FitKit, syringe [1.4%], cotton swab (and ruler), titan cylinders, slide gauge and ultrasonography [1.37%]. The factors relevant to SPL measurement have been incorporated into the proposed SPL INdicator Technique (SPLINT) which is essentially a holistic extension of the "Conventional PL Measurement"technique. Conclusions: There is a wide range of heterogeneity in the technique for estimation of PL across the study cohort; the underlying factors have been identified along with the respective variables, and the SPLINT for SPL has been described. � 2024 Journal of Indian Association of Pediatric Surgeons.Item Diverse Self-Assembled Molecular Architectures Promoted by C-H���O and C-H���Cl Hydrogen Bonds in a Triad of ?-Diketone, ?-Ketoimine, and an Imidorhenium Complex: A Unified Analysis Based on XRD, NEDA, SAPT, QTAIM, and IBSI Studies(American Chemical Society, 2024) Sinha A.; Sen S.; Singh T.; Ghosh A.; Saha S.; Bandyopadhyay K.; Dey A.; Banerjee S.; Gangopadhyay J.X-ray structural elucidation, supramolecular self-assembly, and energetics of existential noncovalent interactions for a triad comprising ?-diketone, ?-ketoimine, and an imidorhenium complex are highlighted in this report. Molecular packing reveals a self-assembled 2D network stabilized by the C-H���O H-bonds for the ?-diketone (benzil), and the first structural report of Brown and Sadanaga stressing on the prevalence of only the van der Waals forces seems to be an oversimplified conjecture. In the ?-ketoimine, the imine nitrogen atom undergoes intramolecular N���H interaction to render itself inert toward intermolecular C-H���N interaction and exhibits two types of C-H���O H-bonds in consequence to generate a self-assembled 2D molecular architecture. The imidorhenium complex features a self-aggregated 3D packing engendered by the interplay of C-H���Cl H-bonds along with the ancillary C-H���?, C���C, and C���Cl contacts. To the best of our knowledge, in rhenium chemistry, this imidorhenium complex unravels the first example of self-associated 3D molecular packing constructed by the directional hydrogen bonds of C-H���Cl type. The presence of characteristic supramolecular synthons, viz., R22(12), R22(16), and R22(14), in the ?-diketone, ?-ketoimine, and imidorhenium complex, respectively, has prompted us to delve into the energetics of noncovalent interactions. Symmetry-adapted perturbation theory analysis has authenticated a stability order: R22(14) > R22(12) > R22(16) based on the interaction energy values of ?25.97, ?9.93, and ?4.98 kcal/mol, respectively. The respective average contributions of the long-range dispersion, electrostatic, and induction forces are 58.5, 32.8, and 8.7%, respectively, for the intermolecular C-H���O interactions. The C-H���Cl interactions experience comparable contribution from the dispersion force (57.9% on average), although the electrostatic and induction forces contribute much less, 28.0 and 14.1%, respectively, on average. The natural energy decomposition analysis has further attested that the short-range, interfragment charge transfer occurring via the lp(O/Cl) ? ?*(C-H) routes contributes 17-25% of the total attractive force for the C-H���O and C-H���Cl interactions. Quantum theory of atoms in molecules analysis unfolds a first-order exponential decay relation (y = 8.1043e-x/0.4095) between the electron density at the bond critical point and the distance of noncovalent interactions. The distances of noncovalent interactions in the lattices are internally governed by the individual packing patterns rather than the chemical nature of the H-bond donors and acceptors. Intrinsic bond strength index analysis shows promise to correlate the electron density at BCP with the SAPT-derived interaction energy for the noncovalent interactions. Two factors: (i) nearly half the HOMO-LUMO energy difference for the imidorhenium complex (?30 kcal/mol) compared to the organics, and (ii) ?60% localization of HOMO over the mer-ReCl3 moiety clearly indicate an enhanced polarizability of the complex facilitating the growth of weak C-H���Cl H-bonds. � 2024 The Authors. Published by American Chemical Society.Item Exploring the Gamma-Ray Enhanced NIR-Luminescence and Cytotoxic Potential of Lanthanide-Naphthalene Dicarboxylate based Metal�Organic Frameworks(Springer, 2024) Rao P.A.; Padhy H.; Bandyopadhyay K.; Rao A.V.; Ganta R.; Bevara S.; Singh B.P.; Kundrapu B.; Saha S.; Malla R.; Mukkamala S.B.In this investigation, we explore the integration of lanthanides into Metal�Organic Frameworks (MOFs) to enable Near-Infrared (NIR) emission. Specifically, we focus on Lanthanide-Naphthalene Dicarboxylate based MOFs (Ln-MOFs), incorporating elements such as Praseodymium (Pr), Samarium (Sm), Dysprosium (Dy), and Erbium (Er). The synthesis of Ln-MOFs is achieved via the hydrothermal method. The structure, morphology, thermal stability, and luminescence properties of synthesized Ln-MOFs have been evaluated through different characterization techniques. Upon photoexcitation at 350�nm, Ln-MOFs show the emission in the Visible and NIR region. Further, the luminescence intensity of Ln-MOFs enhanced by 2�3 folds in the visible region and 6�8 folds in NIR region after exposing to Gamma irradiation at 150�kGy. Cytotoxic effect on the viability of MDA-MB 231 and MDA-MB 468 Triple negative breast cancer (TNBC) cells was evaluated by MTT assay. The results revealed that among all synthesized MOFs, Pr-MOF exhibited an aggressive cytotoxic effect. Additionally, analysis of phase-contrast microscopy data indicates that Pr-MOF induces alterations in the morphology of both MDA-MB 231 and MDA-MB 468 TNBC cells when compared to untreated controls. The findings in this study reveal the utilization of Ln-MOFs for studying cytotoxicity and highlight their ability to enhance near-infrared (NIR) emission when exposed to gamma radiation. � The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.Item Green Light-Triggered Photocatalytic Anticancer Activity of Terpyridine-Based Ru(II) Photocatalysts(American Chemical Society, 2024) Mandal A.A.; Singh V.; Saha S.; Peters S.; Sadhukhan T.; Kushwaha R.; Yadav A.K.; Mandal A.; Upadhyay A.; Bera A.; Dutta A.; Koch B.; Banerjee S.The relentless increase in drug resistance of platinum-based chemotherapeutics has opened the scope for other new cancer therapies with novel mechanisms of action (MoA). Recently, photocatalytic cancer therapy, an intrusive catalytic treatment, is receiving significant interest due to its multitargeting cell death mechanism with high selectivity. Here, we report the synthesis and characterization of three photoresponsive Ru(II) complexes, viz., [Ru(ph-tpy)(bpy)Cl]PF6 (Ru1), [Ru(ph-tpy)(phen)Cl]PF6 (Ru2), and [Ru(ph-tpy)(aip)Cl]PF6 (Ru3), where, ph-tpy = 4?-phenyl-2,2?:6?,2?-terpyridine, bpy = 2,2?-bipyridine, phen = 1,10-phenanthroline, and aip = 2-(anthracen-9-yl)-1H-imidazo[4,5-f][1,10] phenanthroline, showing photocatalytic anticancer activity. The X-ray crystal structures of Ru1 and Ru2 revealed a distorted octahedral geometry with a RuN5Cl core. The complexes showed an intense absorption band in the 440-600 nm range corresponding to the metal-to-ligand charge transfer (MLCT) that was further used to achieve the green light-induced photocatalytic anticancer effect. The mitochondria-targeting photostable complex Ru3 induced phototoxicity with IC50 and PI values of ca. 0.7 ?M and 88, respectively, under white light irradiation and ca. 1.9 ?M and 35 under green light irradiation against HeLa cells. The complexes (Ru1-Ru3) showed negligible dark cytotoxicity toward normal splenocytes (IC50s > 50 ?M). The cell death mechanistic study revealed that Ru3 induced ROS-mediated apoptosis in HeLa cells via mitochondrial depolarization under white or green light exposure. Interestingly, Ru3 also acted as a highly potent catalyst for NADH photo-oxidation under green light. This NADH photo-oxidation process also contributed to the photocytotoxicity of the complexes. Overall, Ru3 presented multitargeting synergistic type I and type II photochemotherapeutic effects. � 2024 American Chemical Society.Item Metal-Free ?-Sulfonylation of ?-Ketothioamides: Access to ?-Sulfonyl-?-Ketoamides and their Photophysical Studies(John Wiley and Sons Inc, 2024) Kumar V.; Ansari M.A.; Yadav A.K.; Singh S.; Bandyopadhyay K.; Saha S.; Singh M.S.Herein, we report a metal and additive-free unprecedented reactivity of ?-ketothioamides with sulfonyl chlorides for the synthesis of previously unreported 2-sulfonyl-3-oxo-N,3-diarylpropanamides via in situ thioamide to amide conversion followed by dehydrohalogenative C?S cross-coupling at room temperature under an open air for the first time. The protocol demonstrates not only its operational simplicity, efficiency, mild condition, and scalability, but also easy to get the diverse a-sulfonyl-?-ketoamides in good to high yields. Additionally, the DFT and photophysical studies supported the proposed mechanism, and revealed unique excitation-dependent emission coupled with ESPT for the synthesized sulfones. � 2024 Wiley-VCH GmbH.Item Metal-Free [2+3] Dipolar Cycloaddition/Denitration Cascade between Nitroalkenes and ?-Diazoesters: Regioselective Access to Functionalized NH?Pyrazoles(John Wiley and Sons Inc, 2024) Kumar G.; Ray S.; Saha S.; Shankar Singh M.An efficient one-pot synthesis of 1H-pyrazoles has been realized via cascade cyclocondensation of ?-nitroalkenes as C2 synthon with ?-diazoesters as C1N2 unit. The reaction proceeds via concomitant formation of two new (C?N & C?C) bonds in one stretch leading to ethyl-5-nitro-4-phenyl-4,5-dihydro-3H-pyrazole-3-carboxylate intermediate, which undergoes base mediated denitration enabling the formation of NH?pyrazoles. This protocol not only features easy operation, catalyst?free conditions, good to high yields, wide scope and late-stage functionalization, but also opens up a new avenue for synthetically demanding and structurally non-traditional pyrazoles. A combination of experimental and DFT studies provide evidence for the proposed mechanism. � 2024 Wiley-VCH GmbH.Item Observation of the multiple magnetic phases in double perovskite Pr1.8La0.2CoFeO6(Elsevier B.V., 2024) Kumar D.; Singh P.; Alam M.; Kumar S.V.; Dixit S.; Bandyopadhyay K.; Dwivedi G.D.; Saha S.; Ghosh A.K.; Chatterjee S.The structural and magnetic properties of the double perovskite Pr1.8La0.2CoFeO6 have been investigated. The X-ray diffraction study shows that the system acquires room-temperature orthorhombic phase with the Pnma space group. The X-ray photoemission spectroscopy (XPS) measurement confirmed that the B-site ions are present in mixed valence states i.e. Co has been found in Co2+ and Co3+ valance states whereas Fe has been found in Fe3+/Fe4+. Magnetic measurements of the system confirm the existence of several fascinating magnetic behaviors, such as long-range canted antiferromagnetism withTN ? 271 K, giant exchange bias, and re-entrant cluster glass phase (TG ? 33 K). Field-dependent magnetization shows a large spontaneous exchange bias; HSEB? 1.8 kOe and giant conventional exchange bias, HCEB? 2.4 kOe at 5 K. Antiferromagnetic materials with large exchange bias can be utilized in high-density spintronic devices. Temperature-dependent Raman study demonstrates that the observed phonon mode exhibits anomalous behavior close to the magnetic transition temperature. Analysis of anomalous softening of phonon mode below TN, clarifies the presence of significant spin-phonon coupling while the magnetostriction effect does not play any significant role in the observed phonon anomaly. � 2024Item Reproductive Biology, Genetics, Evolution, and Diversity in Finger Millet (Eleusine coracana (L.) Gaertn.)(Springer Nature, 2024) Shamkuwar S.; Srivastava K.; Tirkey A.E.; Prakash D.; Madankar K.; Saha S.Finger millet (Eleusine coracana (L.) Gaertn.) is a nutrient-dense climate-resil-ient major grain crop in Asian and African subcontinents. Being future smart food crop, its production will help in improving the livelihood of people by improving nutritional status. Thus, it is essential to understand its floral biology, genetics, origin, evolution, and genetic diversity to achieve the goal of nutritional security in the developing countries. The origin of finger millet traced back to 5000 years, and Africa and India were recognized as the primary and secondary centers of diversity. Finger millet is a highly self-pollinated allotetraploid crop with as low as 1% cross-pollination aided by wind; thus, artificial hybridization techniques can permit its further improvement immensely. Identification of modern emascu-lation techniques like chemically hybridizing agent (ethrel), hot water emascula-tion, cold water, and plastic bag method transformed from traditional to modern production system due to complex architecture and tiny nature of florets of finger millet. Study of genetic diversity for identification of resistance against various biotic and abiotic stresses as well as high calcium, zinc, and iron-containing species helps in classification and improving the overall production aspect of finger millet. Thus, it is vital to preserve the germplasm for the conservation of genetic diversity and understanding the crop in-depth. This chapter discusses the details about finger millet origin, evolution, floral biology, and cytogenetics, and genetic diversity also highlights the germplasm for overall improvement of finger millet. � The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.Item Sonodynamic Cancer Therapy by Mn(I)-tricarbonyl Complexes via Ultrasound-triggered CO Release and ROS Generation(John Wiley and Sons Inc, 2024) Kumar Yadav A.; Singh V.; Acharjee S.; Saha S.; Kushwaha R.; Dutta A.; Koch B.; Banerjee S.A novel ferrocene conjugated Mn(I)-tricarbonyl complex viz [Mn(Fc-tpy)(CO)3Br] (Mn2) where, Fc-tpy=4?-ferrocenyl-2,2?:6?,2??-terpyridine was synthesized and fully characterized along with its non-ferrocene analog [Mn(Ph-tpy)(CO)3Br] Ph-tpy=4?-phenyl-2,2?:6?,2??-terpyridine (Mn1) for ultrasound (US) activated anticancer applications. The X-ray structure of Mn2 confirmed its distorted octahedral geometry. Mn1 and Mn2, for the first time, showed US-triggered release of CO and ROS generation (1O2 and ?OH) in an aqueous solution from any Mn(I)-tricarbonyl complexes, indicating its potential for synergetic CO gas therapy and sonodynamic therapy. The above-mentioned in-solution chemistry was successfully translated into in vitro cellular models. These complexes showed unprecedented US-triggered toxicity against T-cell lymphoma and human breast cancer cells (IC50 for Mn2<1 ?M) while were minimally toxic without US or against normal spleen and human embryonic kidney cells. Mn2 was ca. 12 fold more anticancer active than Mn1, indicating that the ferrocene conjugation augmented the US sensitivity. The apoptotic sonotoxicity of Mn2 was due to US-promoted mitochondrial depolarization via ROS generation and CO release. The apoptosis was triggered by caspase 3 activation. This is the first report of Mn(I)-tricarbonyl-based sonosensitizers for cancer SDT. Overall, this study, for the first time, establishes the effectiveness of 3d metal carbonyls in SDT. � 2024 Wiley-VCH GmbH.Item TBHP-Mediated Intermolecular Radical Coupling and Intramolecular Cyclization Cascade: Access to Furo[2,3-b]quinoxalines and Their Photophysical Study(John Wiley and Sons Inc, 2024) Ray S.; Kumar V.; Singh S.; Bandyopadhyay K.; Saha S.; Shankar Singh M.A cascade one-pot strategy to construct 31 examples of furo-fused quinoxalines in up to 88% yields has been devised from readily accessible ?-ketothioamides and quinoxalin-2-ones in open flask at room temperature under TBHP mediated conditions. Mechanistic studies revealed that the overall reactivity relies on the seamless integration of intermolecular radical coupling and intramolecular cyclization via desulfhydration of C=S bond cleavage. Generation of H2S as the only by-product makes this process highly attractive. Furthermore, the photophysical behavior of the furo-fused quinoxalines has also been studied. � 2023 Wiley-VCH GmbH.Item The crucial role of stability of intercalating agent for DNA binding studies in DMSO/water system(Elsevier B.V., 2024) Bandyopadhyay K.; Verma A.; Pandey A.; Walia R.; Saha S.In recent years, extensive research has been directed towards understanding the interactions between various zinc complexes with DNA, specifically delving into their intercalation and binding behaviors. The binding of zinc complexes to DNA is particularly intriguing due to their distinctive intercalating capabilities. This study unveils a remarkable phenomenon observed with a specific Zn complex, ([B-Zn-N3], where B is a Schiff base ligand), during DNA intercalation investigations in the popular DMSO-Water binary solvent mixture. An unanticipated observation revealed time-dependent changes in the UV�visible absorption spectroscopic studies, coupled with the existence of an isosbestic point. This observation questions the stability of the intercalating agent itself during the intercalation process. The emergence of a decomposed product during the intercalation study has been confirmed through various analytical techniques, including CHN analysis, MALDI mass, XPS, Raman spectroscopy, and Powder XRD. The change in the chemical species on intercalation is further substantiated by theoretical studies, adding depth to our understanding of the intricate dynamics at play during DNA intercalation with the [B-Zn-N3] complex in the DMSO-Water system. � 2024 Elsevier B.V.Item Unravelling structural insights into ligand-induced photoluminescence mechanisms of sulfur dots(Royal Society of Chemistry, 2024) Sahoo S.R.; Mukhopadhyay A.; Mahata S.; Kumari K.; Praneeth N.V.S.; Baksi A.; Khatua S.; Saha S.; Rakshit S.; Goswami N.Sulfur dots (S-QDs) hold promise as a new category of metal-free, luminescent nanomaterials, yet their practical application faces challenges primarily due to a limited understanding of their structure and its impact on their optical properties. Herein, by employing a spectrum of aliphatic and aromatic ligands, we identify the surface structure and composition of S-QDs while delineating the pivotal role of ligands in inducing photoluminescence. Thiol-functionalized ligands, such as 4-mercapto benzoic acid and glutathione, notably promote the formation of both green and blue luminescent S-QDs, boosting a high quantum yield of up to 56%. Further investigation on the synthesis of S-QDs with 4-mercapto benzoic acid unveils the dual role of H2O2: etching sulfur powder and oxidizing the -SH group to -SO2H. These oxidized ligands passivate the S-QD surface through hydrogen bonding. Electrospray ionization mass spectrometry analysis unveils the presence of distinct sulfur species such as [S4(C6H5SO2H)4(H2O)2H]+ and [S6(C6H5SO2H)6(H2O)3H]+, while XPS analysis confirms the existence of zerovalent sulfur and oxidized sulfur species including SO32? and SO42?. Further detailed spectroscopic examination demonstrates that S-QDs predominantly exist as aggregated entities, with the emission wavelength correlating with the degree of aggregation. The absence of photoluminescence in aggregations devoid of ligands underscores the critical role of ligands in the photoluminescence genesis of S-QDs. � 2024 The Royal Society of Chemistry.
