160 results on '"Rawat DS"'
Search Results
2. Pandemic Influenza A (H1N1) 2009 in India: Duration of virus shedding in patients under antiviral treatment
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Gandhoke, I, Rawat, DS, Rai, A, Khare, S, and Ichhpujani, RL
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- 2011
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3. Seroprevalence of transfusion-transmissible infections among replacement and voluntary blood donors in a tertiary care hospital
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Arora, Disha, primary, Garg, Ketan, additional, and Rawat, DS, additional
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- 2017
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4. Levels of HCH residues in human milk samples from Delhi, India
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Pasha St, Basu Dev Banerjee, Q. Z. Hussain, Rawat Ds, B. C. Koner, and S. S. A. Zaidi
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Adult ,Insecticides ,Chromatography, Gas ,Milk, Human ,Health, Toxicology and Mutagenesis ,Pesticide Residues ,India ,General Medicine ,Environmental Exposure ,Toxicology ,World Health Organization ,Pollution ,Environmental protection ,Humans ,Female ,Socioeconomics ,Hexachlorocyclohexane - Abstract
Levels of HCH Residues in Human Milk Samples from Delhi, India B. D. Banerjee, S. S. A. Zaidi, S. T. Pasha, D. S. Rawak, 3 B. C. Koner, Q. Z. Hussain Department of Biochemistry, University College of Medical Sciences and G.T.B. Hospital, University of Delhi, Shahdara, Delhi, 110 095, India Department of Biochemistry, National Institute of Occupational Health, Ahmedabad, 380 016, India Division of Biochemistry and Biotechnology, National Institute of Communicable Diseases, Delhi, 110 054, India
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- 1997
5. Targeted detection of 65 kDa heat shock protein gene in endometrial biopsies for reliable diagnosis of genital tuberculosis.
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Prasad S, Singhal M, Negi SS, Gupta S, Singh S, Rawat DS, and Rai A
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- 2012
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6. Cleft Palate Outcomes and Prognostic Impact of Palatal Fistula on Subsequent Velopharyngeal Function-A Retrospective Cohort Study
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Alistair G Smyth, Jianhua Wu, and Rawat, DS
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Palate, Hard ,Velopharyngeal Insufficiency ,Fistula ,medicine.medical_treatment ,Dentistry ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,030223 otorhinolaryngology ,Retrospective Studies ,Soft palate ,business.industry ,Infant ,Retrospective cohort study ,030206 dentistry ,Prognosis ,United Kingdom ,Cleft Palate ,Palatoplasty ,medicine.anatomical_structure ,Treatment Outcome ,Otorhinolaryngology ,Child, Preschool ,Cleft palate repair ,Palatal fistula ,Oral Surgery ,business - Abstract
Objective: To assess outcomes from cleft palate repair and define the level of impact of palatal fistula on subsequent velopharyngeal function. Design: A retrospective cohort study. Setting: A regional specialist cleft lip and palate center within United Kingdom. Patients, Participants: Nonsyndromic infants born between 2002 and 2009 undergoing cleft palate primary surgery by a single surgeon with audited outcomes at 5 years of age. Four hundred ten infants underwent cleft palate surgery within this period and 271 infants met the inclusion criteria. Interventions: Cleft palate repair including levator palati muscle repositioning with or without lateral palatal release. Main Outcome Measures: Postoperative fistula development and velopharyngeal function at 5 years of age. Results: Lateral palatal incisions were required in 57% (156/271) of all cases. The fistula rate was 10.3% (28/271). Adequate palatal function with no significant velopharyngeal insufficiency (VPI) was achieved in 79% of patients (213/271) after primary surgery only. Palatal fistula was significantly associated with subsequent VPI (risk ratio = 3.03, 95% confidence interval: 1.95-4.69; P < .001). The rate of VPI increased from 18% to 54% when healing was complicated by fistula. Bilateral cleft lip and palate (BCLP) repair complicated by fistula had the highest incidence of VPI (71%). Conclusions: Cleft palate repair with levator muscle repositioning is an effective procedure with good outcomes. The prognostic impact of palatal fistula on subsequent velopharyngeal function is defined with a highly significant 3-fold increase in VPI. Early repair of palatal fistula should be considered, particularly for large fistula and in BCLP cases.
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- 2019
7. Harnessing the Phytochemistry Through Pesticidal Potential of Diverse Elsholtzia Species: A Path to Sustainable Agriculture.
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Kabdal T, Prakash O, Kumar R, Arya S, Rawat DS, and Kumar S
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This study investigates the phytochemical profiles and pesticidal activities of various Elsholtzia species, including E. ciliata, E. flava, E. fruticosa, and E. eriostachya, to discover their bioactive potential for sustainable pest management. Through comparative phytochemical analysis using GC-MS technique, key compounds in the essential oils were identified. The major components were thymoquinone (44.97%) in E. ciliata, shisofuran (28.66%) in E. flava, perillene (50.88%) in E. fruticosa, and pinocarvone (42.41%) in E. eriostachya. Despite variability in chemical composition, all species primarily contained oxygenated monoterpenes. The bioactivity of the oils was evaluated for their nematicidal and herbicidal bioassays. E. ciliata showed the highest egg hatching inhibition and juvenile mortality of M. incognita, while E. flava exhibited the lowest activity. For herbicidal activity, E. eriostachya achieved 96.70% seed germination inhibition, 100% root growth inhibition, and 95.56% shoot growth inhibition. E. flava showed the lowest inhibition in germination, root length, and shoot length at 66.70%, 81.56%, and 85.28%, respectively. The findings revealed significant variations in phytochemical composition and pesticidal efficacy, emphasizing the importance of species selection for pest management. This research highlights the bioactive potential of Elsholtzia species in sustainable pest management strategies., (© 2024 Wiley‐VCH GmbH.)
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- 2024
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8. Comparison of endoscopic tympanoplasty, cartilage vs. temporalis fascia in chronic suppurative otitis media with inactive mucosal disease: A prospective randomised study.
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Nagar A, Prajapati S, Rawat DS, and Aseri Y
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Background: The introduction of endoscopy into middle ear has open up new opportunities for minimal invasive temporal bone surgery. The present study was planned to compare anatomical and functional outcome in patients who underwent endoscope assisted tympanoplasty using cartilage and temporalis fascia graft., Methods: The present prospective observational randomized study was carried out in the Department of Otorhinolaryngology of a tertiary care teaching hospital of Rajasthan, India from September 2020 to July 2021. Fifty patients of age group 18-60 years, with diagnosis of chronic otitis media having inactive mucosal disease were enrolled in the study and divided into two groups viz. cartilage (group I) and temporalis fascia group (group II). Each patient postoperatively underwent otoscopic examination of ear and pure tone audiometery at 8 weeks and 3rd month. Local wound condition, graft uptake and healing and hearing were assessed and compared., Results: Graft uptake was 92% in cartilage group and 84% in temporalis fascia group. Air conduction and air-bone gap of patients in both the groups showed significant improvement after 3 months of surgery. (p˂0.05) Regarding bone conduction, both groups had shown non-significant changes. (p > 0.05) Hearing gain was comparable on both groups which was 6.71dB in cartilage group vs. 5.9 dB in other group., Conclusions: The present study showed that graft placement time for temporalis fascia graft was less than cartilage graft, but the difference was insignificant. Hearing improvement, graft uptake and clinical improvement were found to be statistically insignificant between both groups., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2024
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9. CBNAAT: An Emerging Xpert in Diagnosis of Head and Neck Tuberculosis.
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Sahu R, Prajapati S, Kumar A, Aseri Y, Rawat DS, Kuldeep R, and Baniya R
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Aims and Obctives: To compare FNAC, microscopy (ZN staining), histopathology and CBNAAT for diagnosis of head and neck tuberculosis, and to evaluate efficacy of CBNAAT in early diagnosis of tuberculosis in head and neck region., Materials and Methods: This prospective study was carried out in the department of otorhinolaryngology, JLN Medical College and attached hospital, Ajmer from August 2020 to September 2022. Thorough history and clinical examination of all patients presented with neck swelling was done. All relevant investigations including chest x-ray, mantoux test, ESR, FNAC, ZN staining, CBNAAT and histopathology were done and their efficacy was compared., Results: Sensitivity and specificity of CBNAAT in detecting extra pulmonary tuberculosis was 85.19% and 91.30% respectively, and diagnostic accuracy was consistent with findings of FNAC and ZN staining ( p < 0.001) for diagnosis of cervical lymphadenopathy., Conclusion: CBNAAT has a promising role in early diagnosis of head and neck tuberculosis as well as other cases of smear negative tuberculosis such as MDR TB and TB-HIV and is optimal for the diagnosis of lymph node tuberculosis and helps in early identification and initiation of treatment. Sensitivity of CBNAAT scored twice as high in comparison with microscopy thus doubling the proportion of rapid diagnoses with important effect on the patient's outcome., Competing Interests: Conflict of interestThe authors have no competing interest to declare that are relevant to the content of this article., (© Association of Otolaryngologists of India 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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10. Nano Encapsulation of An Essential Oil Transpire the Therapeutic Approach.
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Chhetri S, Arora S, Parcha V, Kumar D, and Rawat DS
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Essential oils are natural compounds extracted from plants that are volatile and sensitive to heat. Due to their therapeutic value, essential oils are now used in many industries, including the sanitary, cosmetic, agricultural, food, and pharmaceutical industries. These are complex mixtures of a wide range of volatile molecules, including phenol-derived aliphatic and aromatic compounds and terpenoids. Essential oils have been used medicinally since ancient times for their antibacterial, antifungal, antiviral, antiparasitic, insecticidal, sedative, antiinflammatory, and anaesthetic properties. However, essential oils come with inherent limitations; thus, nanoencapsulation is advocated as a remedy as it has the potential to enhance the stability, solubility, and effectiveness of formulations based on essential oils, all while preserving the therapeutic drug blood levels. It is not always viable to use essential oils independently in treatment due to several restrictions; however, nanodelivery technologies appear capable of overcoming these challenges. The therapeutic efficacy that is achieved can be affected by several factors, including the selection of the essential oil as well as the system of nanodelivery. Today, nanoencapsulation is capable of enabling the simultaneous delivery of multiple oils, providing synergistic effects, and facilitating the development of combinational therapies. Additionally, they may have potential applications in preserving food to prolong the shelf life of quickspoiling items and their fragrances. While there is already much research on the characterisation of EOs, this review evaluates the features of the nanoparticles employed for the delivery of essential oils and their impact on the functionality of nano-delivered essential oils and their beneficial uses., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2024
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11. Air Induced Phosphoryl Radical Mediated Stereoselective Hydrosulfonylation of Alkynes via Halogen Atom Transfer: Ingress of Z -Vinyl Sulfones.
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Tiwari S, Kumari M, and Rawat DS
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The phosphoryl radical is well-known to participate in addition reactions with alkenes/alkynes. Here, we report a novel reaction mode of the phosphoryl radical where it participates in halogen atom transfer (XAT) with electron deficient vinyl halides instead of a facile addition reaction. Nevertheless, in comparison with aryl and alkyl halides, the exploitation of vinyl halides into a carbon radical via XAT is quite rare. This protocol provides an opportunity for direct hydrosulfonylation of numerous internal as well as terminal alkynes to get various Z -vinyl sulfones under environmentally benign conditions. Generation of the phosphoryl radical in the open air, water as a solvent, excellent functional group compatibility, and exceptional chemoselectivity are the attractive features of the present methodology.
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- 2024
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12. A Comparative Study of Endoscopic Assisted Powered Adenoidectomy Versus Conventional Adenoidectomy.
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Beemrote DS, Aseri Y, Rawat DS, Mahich S, and Verma PC
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Adenoidectomy is one of the most common procedures performed in children today, either alone or in conjunction with tonsillectomy or insertion of ventilating tubes. The present study was planned to compare the endoscopic powered adenoidectomy versus conventional adenoidectomy. The present prospective observational randomized study was carried out in the Department of Otorhinolaryngology of a tertiary care teaching hospital of Rajasthan. Fifty patients with adenoid hypertrophy in the age group between 5-13 years were enrolled in the study and divided in to two groups viz. cases undergoing conventional adenoidectomy using curettage method (group A = 25) and cases undergoing endoscopic powered adenoidectomy (group B = 25). Intra operative time, primary bleeding, completeness of adenoid removal, depth of resection, and collateral damage were noted intra operatively in both the groups. Postoperative pain, recovery time, postoperative complications were also compared. Intra operative time taken in Group A was 25.6 ± 2.90 min while it was 35.04 ± 5.24 min in Group B. (p < 0.0001) Average blood loss in Group A was 18.4 ± 4.72 ml compared to an average blood loss of 29.32 ± 2.59 ml in Group B. (p < 0.0001) The postoperative recovery time in Group A was 4.93 days and it was 3.06 days in group B. (p = 0.00). The present study concluded that newer method of endoscopic powered adenoidectomy was found to be a safe and useful tool for adenoidectomy in terms of completeness of resection, better control of depth of resection and minimal collateral damage intra-operatively and less postoperative pain, complications and fast recovery period., Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-023-03633-4., Competing Interests: Conflicts of interest/Competing InterestsNone., (© Association of Otolaryngologists of India 2023. 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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- 2023
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13. Giloy: a potential anti-COVID-19 herb with propitious pharmacological attributes: a short review.
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Arora S, Goyal A, Rawat DS, and Samantha K
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Plant-based medicine actually restores the balance in the body instead of treating the source of the disease. The strain of coronavirus (SAR-CoV-2) going to be more serious due to the lack of a reliable treatment option. Holistic treatment for this disease is in the form of Ayurveda as traditional medicine. As the infection of coronavirus is spreading like a wildfire, so the one way to fight is 'immunity'. Building immunity is the only way to stay safe and healthy and prepared themselves for the ongoing pandemic. In the current scenario, good immunity safeguard us from disease progression and prevention from this deadly virus. Giloy herb came into the limelight after the start of the COVID-19 pandemic due to its immunomodulatory and antiviral activity. The genome sequencing of Giloy is proved to be a breakthrough for controlling the COVID-19.Communicated by Ramaswamy H. Sarma.
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- 2023
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14. An optimized Nurr1 agonist provides disease-modifying effects in Parkinson's disease models.
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Kim W, Tripathi M, Kim C, Vardhineni S, Cha Y, Kandi SK, Feitosa M, Kholiya R, Sah E, Thakur A, Kim Y, Ko S, Bhatia K, Manohar S, Kong YB, Sindhu G, Kim YS, Cohen B, Rawat DS, and Kim KS
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- Mice, Animals, Male, Dopaminergic Neurons metabolism, Mesencephalon metabolism, Brain metabolism, Disease Models, Animal, Nuclear Receptor Subfamily 4, Group A, Member 2 genetics, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism, Parkinson Disease drug therapy, Parkinson Disease pathology, Neuroprotective Agents pharmacology, Neuroprotective Agents therapeutic use
- Abstract
The nuclear receptor, Nurr1, is critical for both the development and maintenance of midbrain dopamine neurons, representing a promising molecular target for Parkinson's disease (PD). We previously identified three Nurr1 agonists (amodiaquine, chloroquine and glafenine) that share an identical chemical scaffold, 4-amino-7-chloroquinoline (4A7C), suggesting a structure-activity relationship. Herein we report a systematic medicinal chemistry search in which over 570 4A7C-derivatives were generated and characterized. Multiple compounds enhance Nurr1's transcriptional activity, leading to identification of an optimized, brain-penetrant agonist, 4A7C-301, that exhibits robust neuroprotective effects in vitro. In addition, 4A7C-301 protects midbrain dopamine neurons in the MPTP-induced male mouse model of PD and improves both motor and non-motor olfactory deficits without dyskinesia-like behaviors. Furthermore, 4A7C-301 significantly ameliorates neuropathological abnormalities and improves motor and olfactory dysfunctions in AAV2-mediated α-synuclein-overexpressing male mouse models. These disease-modifying properties of 4A7C-301 may warrant clinical evaluation of this or analogous compounds for the treatment of patients with PD., (© 2023. The Author(s).)
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- 2023
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15. Regiodivergent Synthesis of Densely Functionalized Indolizines via (2 + 2 + 1) Cycloaddition.
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Tiwari S and Rawat DS
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A novel metal and additive free, atom-economic method for the regiodivergent synthesis of crucial 6- or 8-substituted indolizine from meta -amide-substituted pyridine and alkyne via a [2 + 2 + 1] cycloaddition is developed. The reaction proceeds through the cleavage of the carbon-carbon triple bond. The synthesized product contains an important amide group that can be further functionalized to afford biologically active compounds.
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- 2023
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16. Mesoporous Copper-Magnesium Oxide Hybrid Nanocatalyzed Synthesis of 3-Substituted Isocoumarins from 2-Iodobenzoic Acid and Terminal Alkyne under Green Conditions.
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Rawat M and Rawat DS
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A 3-substituted isocoumarin scaffold has captivated extensive interest in synthetic and medicinal chemistry due to its presence in various natural products with diverse biological activities. Herein, we report a mesoporous CuO@MgO nanocomposite that was prepared via the sugar-blowing induced confined method with an E -factor of 12.2 and its catalytic potential in the facile synthesis of 3-substituted isocoumarin from 2-iodobenzoic acids and terminal alkynes. Powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller techniques were utilized for the characterization of the as-prepared nanocomposite. A broad substrate scope, mild reaction conditions, excellent yield in short reaction time, no usage of additives, and better green chemistry metrices such as a low E -factor (0.71), high reaction mass efficiency (58.28%), low process mass efficiency (1.71), and high turnover number (629) are the various advantages of the present synthetic route. The nanocatalyst was recycled and reused up to five runs without significant loss in its catalytic activity and a very low leaching of copper (3.20 ppm) and magnesium ions (0.72 ppm). Powder X-ray diffraction and high-resolution transmission electron microscopy techniques confirmed the structural integrity of the recycled CuO@MgO nanocomposite., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)
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- 2023
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17. Phytochemical Screening and Evaluation of Pesticidal Efficacy in the Oleoresins of Globba sessiliflora Sims and In Silico Study.
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Verma B, Karakoti H, Kumar R, Mahawer SK, Prakash O, Srivastava RM, Kumar S, Rawat S, Rawat DS, and de Oliveira MS
- Abstract
Globba sessiliflora Sims is an aromatic rhizomatous herb of family Zingiberaceae which is endemic to Peninsular India. This study first reports the phytochemical profile and pesticidal potential of oleoresins obtained from the aerial and rhizome parts of Globba sessiliflora Sims. The oleoresins were prepared by the cold percolation method and were analyzed by a gas chromatography-mass spectrometry (GC-MS) method. Both the oleoresins varied greatly in composition, the major compounds identified in aerial part oleoresin (GSAO) were methyl linoleate, methyl palmitate, and phytol, while the major compounds present in rhizome part oleoresin (GSRO) were γ -sitosterol, 8 (17),12-labdadiene-15, 16-dial, methyl linoleate, and methyl palmitate. In order to evaluate the biological activities, the oleoresins were tested under laboratory conditions for nematicidal action and inhibition of egg hatching potential against root knot nematode, where GSRO was more effective. Insecticidal activity was performed against mustard aphid, Lipaphis erysimi and castor hairy caterpillar, Selepa celtis . In case of mustard aphid, GSRO (LC
50 = 154.8 ppm) was more effective than GSAO (LC50 = 263.0 ppm), while GSAO (LC50 = 346.7.0 ppm) was more effective against castor hairy caterpillar than GSRO (LC50 = 398.1 ppm). The herbicidal activity was performed in the receptor species Raphanus raphanistrum subsp. sativus , and the oleoresins showed different intensities for seed germination inhibition and coleoptile and radical length inhibition. Molecular docking studies were conducted to screen the in vitro activities and through molecular docking, it was found that the major oleoresins components were able to interact with the binding pocket of HPPD and AChE with γ -sitosterol showing the best binding affinity., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2023 Bhawna Verma et al.)- Published
- 2023
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18. A Comprehensive Review on Phytochemistry, Ethnopharmacology, and Pharmacological Properties of Zingiber roseum (Roxb.) Roscoe.
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Mahawer SK, Kumar R, Prakash O, Arya S, Singh S, de Oliveira MS, and Rawat DS
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- Ethnopharmacology, Phytochemicals pharmacology, Phytochemicals chemistry, Phytotherapy, Plant Extracts chemistry, Plants, Medicinal, Zingiberaceae
- Abstract
Medicinal and aromatic plants are known to have a number of biologically active compounds. Since ancient times, such plants have been used in ethnopharmacology. A number of medicines have been developed from plant origin by researchers and researchers continue to be interested in plant-based medicines. Zingiberaceae is a well-known plant family for such types of medicinal and aromatic plants. Zingiber is the third largest genus of this family and Zingiber roseum (Roxb.) Roscoe is a medicinal and aromatic Z. roseum is a rhizomatous perennial herbaceous plant of this genus, popularly known as "Rosy Ginger" and "Jangli Adrak," utilized in the Siddha arrangement of medication, and its rhizomes have been used to treat injury, cough, asthma, skin illnesses, gastric ulcers, liver diseases, and heartburn in tradition. It also has ethnopharmacological uses, such as the rhizome of Z. roseum is used for digestion, relieving giddiness, and as a stimulant. Apart from this, it has been reported for several pharmacological activities such as antispasmodic, hepatoprotective, antimicrobial, and anticancer activities, etc. Z. roseum is a reservoir of several chemical constituents such as terpenes and terpenoids such as linalool, α-pinene, β-pinene, limonene, terpinen-4-ol, α- terpineol, etc., phenols, flavonoids, alkaloids, saponins, and ascorbic acid along with important unique constituents such as zerumbone which are responsible for its medicinal and other biological activities. In this review article, we discussed the thorough knowledge published by researchers regarding the phytochemistry, ethnopharmacological, and mediational properties of Z. roseum and its botanical descriptions., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2023
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19. NSC19723, a Thiacetazone-Like Benzaldehyde Thiosemicarbazone Improves the Efficacy of TB Drugs In Vitro and In Vivo .
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Singh P, Rawat S, Agrahari AK, Singh M, Chugh S, Gurcha S, Singh A, Abrahams K, Besra GS, Asthana S, Rawat DS, and Singh R
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- Humans, Animals, Mice, BCG Vaccine, Mycolic Acids pharmacology, Benzaldehydes pharmacology, Molecular Docking Simulation, Antitubercular Agents pharmacology, Antitubercular Agents therapeutic use, Thioacetazone pharmacology, Thiosemicarbazones pharmacology, Mycobacterium tuberculosis
- Abstract
The complexity and duration of tuberculosis (TB) treatment contributes to the emergence of drug resistant tuberculosis (DR-TB) and drug-associated side effects. Alternate chemotherapeutic agents are needed to shorten the time and improve efficacy of current treatment. In this study, we have assessed the antitubercular activity of NSC19723, a benzaldehyde thiosemicarbazone molecule. NSC19723 is structurally similar to thiacetazone (TAC), a second-line anti-TB drug used to treat individuals with DR-TB. NSC19723 displayed better MIC values than TAC against Mycobacterium tuberculosis and Mycobacterium bovis BCG. In our checkerboard experiments, NSC19723 displayed better profiles than TAC in combination with known first-line and recently approved drugs. Mechanistic studies revealed that NSC19723 inhibits mycolic acid biosynthesis by targeting the HadABC complex. Computational studies revealed that the binding pocket of HadAB is similarly occupied by NSC19723 and TAC. NSC19723 also improved the efficacy of isoniazid in macrophages and mouse models of infection. Cumulatively, we have identified a benzaldehyde thiosemicarbazone scaffold that improved the activity of TB drugs in liquid cultures, macrophages, and mice. IMPORTANCE Mycobacterium tuberculosis, the causative agent of TB is among the leading causes of death among infectious diseases in humans. This situation has worsened due to the failure of BCG vaccines and the increased number of cases with HIV-TB coinfections and drug-resistant strains. Another challenge in the field is the lengthy duration of therapy for drug-sensitive and -resistant TB. Here, we have deciphered the mechanism of action of NSC19723, benzaldehyde thiosemicarbazone. We show that NSC19723 targets HadABC complex and inhibits mycolic acid biosynthesis. We also show that NSC19723 enhances the activity of known drugs in liquid cultures, macrophages, and mice. We have also performed molecular docking studies to identify the interacting residues of HadAB with NSC19723. Taken together, we demonstrate that NSC19723, a benzaldehyde thiosemicarbazone, has better antitubercular activity than thiacetazone.
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- 2022
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20. Dissecting The role of Plasmodium metacaspase-2 in malaria gametogenesis and sporogony.
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Kumari V, Prasad KM, Kalia I, Sindhu G, Dixit R, Rawat DS, Singh OP, Singh AP, and Pandey KC
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- Animals, Gametogenesis, Humans, Plasmodium berghei genetics, Sporozoites metabolism, Malaria parasitology, Protozoan Proteins genetics, Protozoan Proteins metabolism
- Abstract
The family of apicomplexan specific proteins contains caspases-like proteins called "metacaspases". These enzymes are present in the malaria parasite but absent in human; therefore, these can be explored as potential drug targets. We deleted the MCA-2 gene from Plasmodium berghei genome using a gene knockout strategy to decipher its precise function. This study has identified that MCA-2 plays an important role in parasite transmission since it is critical for the formation of gametocytes and for maintaining an appropriate number of infectious sporozoites required for sporogony. It is noticeable that a significant reduction in gametocyte, oocysts, ookinete and sporozoites load along with a delay in hepatocytes invasion were observed in the MCA-2 knockout parasite. Furthermore, a study found the two MCA-2 inhibitory molecules known as C-532 and C-533, which remarkably inhibited the MCA-2 activity, abolished the in vitro parasite growth, and also impaired the transmission cycle of P. falciparum and P. berghei in An. stephensi . Our findings indicate that the deletion of MCA-2 hampers the Plasmodium development during erythrocytic and exo-erythrocytic stages, and its inhibition by C-532 and C-533 critically affects the malaria transmission biology.
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- 2022
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21. Encapsulated Follicular Variant of Papillary Thyroid Carcinoma: A review on Surgical Treatment.
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Sharma AK, Jain K, Singhal P, Rawat DS, Jain SK, and Sharma S
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Differentiated thyroid carcinoma is one of the commonest malignancies in head and neck region. Among differentiated thyroid carcinoma, papillary carcinoma is the commonest. Encapsulated follicular variant of papillary thyroid carcinoma tumors are very indolent tumors which behave like benign tumors. Many tumors have been over diagnosed and over treated in spite of their indolent nature. We aimed to find out if total thyroidectomy is really required for very low grade tumors like encapsulated FVPTC. We operated 672 patients of thyroid disease during 2012 to 2020 in SMS Medical College, Jaipur. Out of 256 patients, 199 patients (78%) had papillary carcinoma of thyroid. Classical variant was present in 40% and follicular variant was present in 35% ( N -69). Out of 69 patients with follicular variant of PTC, 59 patients had well encapsulated type of follicular variant of PTC while 10 patients had invasive type of follicular variant of PTC. Encapsulated FVPTC are less aggressive and indolent tumors. They should be treated more conservatively. Hemithyroidectomy is sufficient treatment for its complete cure. Out of 69 patients with Follicular variant of PTC, 59 patients had encapsulated disease. Out of 59 patients, 14 (24%) had bilateral nodular disease. 45 (77%) patients had unilateral disease; multicentric in one lobe in 9 (15%) patients and unicentric in 36 (61%) patients. However, encapsulated FVPTC was only found in predominant lobe and the non dominant lobe had benign disease., Competing Interests: Conflict of interestThere are no conflicts of interest among authors and others., (© Association of Otolaryngologists of India 2022.)
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- 2022
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22. C3 regioselectivity: a major constraint in the drug development with imidazo[1,2- a ]pyridines.
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Prasher P, Sharma M, Sharma M, and Rawat DS
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- Structure-Activity Relationship, Drug Development, Pyridines, Imidazoles
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- 2022
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23. A prospective longitudinal study of clinical outcome and quality of life assessment in patients with chronic rhinosinusitis after functional endoscopic sinus surgery using sino nasal outcome test-22.
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Verma P, Rawat DS, Aseri Y, Verma PC, and Singh BK
- Abstract
Chronic rhinosinusitis (CRS) significantly affect the quality of life (QoL) of patients. The study was conducted in CRS patients who were treated with functional endoscopic sinus surgery (FESS) after failure of medical treatment to analyze clinical outcome using prospectively collected data through a symptom-based rhinosinusitis outcome measure, the Sino-nasal Outcome Test-22 (SNOT-22). The aim of the study was to evaluate and compare the QoL in patients of chronic rhinosinusitis pre-operative and after FESS by SNOT-22. The prospective study was conducted on 40 patients of chronic rhinosinusitis with or without nasal polyposis. Demographic, clinical, diagnostic nasal endoscopy and radiological findings were recorded. Visual analogue scoring and SNOT-22 questionnaire scoring were done preoperatively and at 3rd and 6th months post-operatively. These scores were compared and a value of p < 0.01 was considered statistical significant. Nasal obstruction (80%) was the most commonly reported disabling condition followed by rhinorrhea (75%), facial pain-pressure (72.5%), headache and sneezing. The mean preoperative nasal endoscopy score was 8.08 ± 3.65. The mean preoperative Lund Mackay CT scan score was 11.725 ± 3.64. The mean preoperative SNOT-22 score was 46.25 ± 20.44. After FESS, nasal discharge was improved in 86% patients. Average VAS scores showed significant postoperative improvement at 6 months ( p < 0.01). The mean postoperative diagnostic nasal endoscopy score improved to 2.80 ± 1.64 at 6 months ( p < 0.01). The mean postoperative SNOT-22 scores decreased at postoperative follow up visits at 3 and 6 months to 14.58 ± 4.90 at 3 months and 22.38 ±7.93 at 6 months ( p < 0.01). CRS patient refractory to medical treatment showed statistical significant improvement after FESS. The SNOT-22 scoring was easy to use scoring used for QoL assessment showed significant improvement after FESS., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Otolaryngologists of India 2020.)
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- 2022
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24. Giant Pleomorphic Adenomas of Parotid Gland: a Case Series.
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Pareek YK, Gupta D, Aseri Y, Rawat DS, Singh BK, and Verma PC
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The parotid gland is the largest salivary gland in the body. Pleomorphic adenomas (PA) are most common benign tumors of parotid gland. If left untreated, they can gradually attain the size which can weigh several kilograms. This paper highlights a case series of 15 cases diagnosed as giant pleomorphic adenoma arising in the parotid gland along with their management. A hospital based, observational study of 15 patients of PA of the parotid gland, > 10 cm in its widest dimension considered as giant, done at tertiary care ENT hospital over period of 9 years. The age of the patients ranged from 30 to 81 years with mean age 50.33 ± 15.30 years. There were 5(33.33%) males and 10(66.67%) females. The time duration of having tumor ranged from 5 to 20 years with mean duration of 10.4 ± 4.17 years and the largest tumor was 25 cm in its largest diameter. Mean weight of tumors was 2.72 ± 0.52 kg. One out of fifteen cases was detected as malignant in nature. All cases were treated by surgical excision without any complications. Pleomorphic adenoma of parotid gland can assume a giant proportion when timely surgical intervention is not done. We can build up confidence and hope for life in patients after complete surgical excision of giant PA., Competing Interests: Conflict of interestThe authors declare that they have no competing interests., (© Association of Otolaryngologists of India 2020.)
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- 2022
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25. Phytochemical Profile, In Vitro Bioactivity Evaluation, In Silico Molecular Docking and ADMET Study of Essential Oils of Three Vitex Species Grown in Tarai Region of Uttarakhand.
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Karakoti H, Mahawer SK, Tewari M, Kumar R, Prakash O, de Oliveira MS, and Rawat DS
- Abstract
A comparative study of volatiles, antioxidant activity, phytotoxic activity, as well as in silico molecular docking and ADMET study, was conducted for essential oils from three Vitex species, viz., V. agnus-castus , V. negundo , and V. trifolia . Essential oils (OEs) extracted by hydrodistillation were subjected to compositional analysis using GC-MS. A total number of 37, 45, and 43 components were identified in V. agnus-castus , V. negundo , and V. trifolia , respectively. The antioxidant activity of EOs, assessed using different radical-scavenging (DPPH, H
2 O2 and NO), reducing power, and metal chelating assays, were found to be significant as compared with those of the standards. The phytotoxic potential of the EOs was performed in the receptor species Raphanus raphanistrum (wild radish) and the EOs showed different levels of intensity of seed germination inhibition and root and shoot length inhibition. The molecular docking study was conducted to screen the antioxidant and phytotoxic activity of the major and potent compounds against human protein target, peroxiredoxin 5, and 4-hydroxyphenylpyruvate dioxygenase protein (HPPD). Results showed good binding affinities and attributed the strongest inhibitory activity to 13- epi -manoyl oxide for both the target proteins.- Published
- 2022
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26. Design and synthesis of benzimidazole derivatives as antimycobacterial agents.
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Sindhu G, Kholiya R, Kidwai S, Singh P, Singh R, and Rawat DS
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- Antitubercular Agents pharmacology, Benzimidazoles pharmacology, Microbial Sensitivity Tests, Structure-Activity Relationship, Isoniazid pharmacology, Mycobacterium tuberculosis
- Abstract
A series of 2,5-disubstituted benzimidazole derivatives was synthesized with the aim to identify compounds with potent anti-TB activity. All the compounds were screened in vitro against cultured Mycobacterium tuberculosis H
37 Rv strain and found to be exhibiting MIC99 values in the range of 0.195-100 µM. Out of 43 synthesized compounds, two compounds 11h and 13e showed better anti-TB activity than the reference drug isoniazid., (© 2022 Wiley Periodicals LLC.)- Published
- 2022
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27. Comparative study on eucalyptol and camphor rich essential oils from rhizomes of Hedychium spicatum Sm. and their pharmacological, antioxidant and antifungal activities.
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Rawat A, Rawat M, Prakash OM, Kumar R, Punetha H, and Rawat DS
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- Animals, Antifungal Agents pharmacology, Antioxidants analysis, Camphor analysis, Camphor pharmacology, Eucalyptol analysis, Ibuprofen analysis, Ibuprofen pharmacology, Inflammation, Mice, Plant Oils chemistry, Rhizome chemistry, Ibuprofen chemistry, Oils, Volatile chemistry, Zingiberaceae chemistry
- Abstract
The aim of present study was to evaluate chemical composition and different biological activities viz., pharmacological and antioxidant activities of essential oils. The chemical composition of essential oils was determined by gas chromatography/mass spectrometry while biological activities were evaluated by standard protocols. Essential oils of Hedychium spicatum Sm. from two different ecological niches viz; Nainital (Site-I) and Himachal Pradesh (Site-II) of India revealed the qualitative and quantitative chemo-diversity. Both the oils were dominated by oxygenated terpenoids. Major marker compounds identified were eucalyptol, camphor, linalool, α-eudesmol, 10-epi-γ-eudesmol, and iso-borneol. Both the oils exhibited anti-inflammatory activity suppressing 17.60 % to 33.57 % inflammation at 100mg/kg b. wt. dose levels compared to ibuprofen-treated group (40.06 %). The sub-acute inflammation in oils-treated mice groups (50 and 100 mg/kg b. wt.) increased on day 2 but showed a gradual decrease from day 3 onwards and then recovered to normal by day 10. The antinociception percentage for doses (50 and 100 mg/kg b. wt.) ranged from 33.70-40.46 % in Site-I and 30.34-42.39 % in Site-II compared to standard drug, ibuprofen (43.08 %). The oils also showed a good antipyretic effect by suppressing Brewer's yeast (Saccharomyces cerevisiae) induced pyrexia after oil dose injection. The oils also exhibited good antioxidant activity.
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- 2022
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28. A Prospective Randomized Study to Compare Surgical Outcome Using Wet and Dry Temporalis Fascia Graft in Type I Tympanoplasty.
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Sharma S, Rawat DS, Aseri Y, Trivedi GP, Verma PC, and Singh BK
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Temporalis fascia is being used as graft material for tympanic membrane repair for over six decades. Though cartilage with or without perichondrium is also being used for different situations, still temporalis fascia graft is being considered as an ideal graft for tympanoplasty. Earlier the dried temporalis fascia was used as a graft but now freshly taken wet temporalis fascia is increasingly being used as a more 'physiological/ live' graft. The present study was planned to compare the results of use of wet and dry temporalis fascia in chronic otitis media mucosal disease. The prospective study was conducted on 100 patients of chronic suppurative otitis media mucosal disease. Chronic ear survey questionnaire were filled to note the impact on quality of life. Otoscopic, oto-endoscopic and examination under microscope performed. Patients were allocated into two groups alternately. Freshly taken wet temporalis graft was used in group I whereas dry temporalis fascia was used in group II. Hearing evaluation by pure tone audiogram was done preoperatively and at 6th months post-operatively. Pre-operative and post-operative hearings in both the groups were compared. Air bone gap closures after surgery in between both the groups were compared to see for any statistical difference. We found similar graft uptake in both the groups after 6 months of surgery. The air bone gap closure in group I was 10.80 ± 5.74 and group II was 9.28 ± 4.81, there was no significant difference. However senior authors noted that in some of the cases in group I with fresh wet graft placement neo-tympanum formation was noticed early showing good circumferential leash of blood vessels all around signifying early vascularisation., Competing Interests: Conflict of interestAuthors declare no conflict of interest., (© Association of Otolaryngologists of India 2020.)
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- 2022
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29. A Prospective Longitudinal Study to Evaluate the Patency of the Aditus ad Antrum in Chronic Otitis Media Mucosal Type.
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Lakhawat R, Rawat DS, Aseri Y, Verma PC, and Singh BK
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Chronic otitis media is defined as the chronic inflammation of the mucoperiosteal lining lining of the middle ear cleft which presents with recurrent ear discharge through tympanic membrane perforation. The study was planned to evaluate the patency of the aditus ad antrum in cases of chronic otitis media mucosal type, and its correlation with various direct and indirect indicators of blocked aditus. The prospective longitudinal study was conducted on 100 patients with chronic otitis media mucosal type. The commonest complaint of patients was ear discharge (100%) followed by hearing impairment in 72% patients.Tympanoplasty with antrotomy was performed. The patency and dimensions of the aditus ad antrum were assessed by saline water test. In 41% cases saline test showed blockade, on further drilling patency achieved in 27 cases with minimal drilling and dissection of mucosa with or without fibrotic mucosal bands. In rest 14 cases widening of aditus and atticotomy was required to achieve patency. Out of these nine were having associated tympanosclerosis and five were having edematous mucosa. Ossicular necrosis was seen on 18 cases. Presence of myringosclerosis and polypoidal edematous mucosa increases the probability of an obstructed aditus ad antrum. Mastoid antrostomy and water test for patency can be performed without additional cost and risk to the patient in minimal time and can be considered as the surest indicator of patency of aditus ad antrum., Competing Interests: Conflict of interestAuthors declare that they have no conflict of interest., (© Association of Otolaryngologists of India 2020.)
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- 2022
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30. A Prospective Longitudinal Study to Evaluate the Outcomes of Success of Endoscopic DCR in Pediatric Age Group.
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Poonia R, Aseri Y, Rawat DS, and Singh BK
- Abstract
Children with nasolacrimal duct obstruction (NLDO) have different therapeutic approach from that used in adults. Dacryocystorhinostomy (DCR) is the most common procedure in adults but it is less frequently carried out in children, indicated in children which are refractory to probing. The objective of the study is to report a series of 30 cases of paediatric epiphora who underwent endoscopic endonasal dacryocystorhinostomy surgery, for primary obstruction of nasolacrimal duct and results, outcomes of success are evaluated. This is a prospective and non-comparative review of 30 cases of epiphora aged between 3 and 9 years from April 2018 to March 2019. The main outcome measures assessed were determined by the resolution of symptoms and the patency of the lacrimal anatomy confirmed by syringing or irrigating the nasolacrimal duct. Secondary outcomes included the presence of such complications as bleeding, scarring, and/or persistent epiphora and infection. In our study 30 patients underwent unilateral DCR surgery in NLDO. Out of 30 patients males were 17 and females were 13. The overall success rate of endoscopic DCR was 90%, and failed cases were mainly due to pre-saccal obstruction. No major complications were reported, minor complications occurred in about 60% of cases. Analysis of the results indicated that EDCR was safe and an effective therapeutic approach for treating nasolacrimal duct obstruction in pediatric age group patients having NLDO. It's considered as an alternative procedure to external dacryocystorhinostomy after a failed conservative treatment., Competing Interests: Conflicts of interestAuthors involved in this trial have no conflict of interest., (© Association of Otolaryngologists of India 2020.)
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- 2022
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31. Evaluation of Recurrence and Hearing Outcome for Inactive Squamosal Disease after Cartilage Strengthening Tympanoplasty.
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Gupta P, Rawat DS, Aseri Y, Verma PC, and Singh BK
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Introduction Inactive squamosal disease is unique for having a conflicting treatment protocol, with an age-old debate between early surgical intervention or keeping patients in a long-term follow-up. The shifting paradigm is early intervention to prevent further progress into active disease and improve hearing outcome in its nascent stage. Objective To evaluate recurrence and hearing outcome in cases of inactive squamosal disease after cartilage strengthening tympanoplasty. Methods The study was conducted on 50 patients with inactive squamosal disease. Detailed examination was done to grade the retraction. All patients underwent autologous conchal cartilage tympanomastoidectomy with temporalis fascia grafting. Recurrence and hearing evaluations were done by pure tone audiogram at regular intervals for one year. Results Hearing loss was the most common presenting symptom. Isolated pars tensa retractions were more common (54%) than pars flaccida (12%), or those involving both (34%). Ossicular status was normal in only 14% of the cases, and the most common ossicular damage was to the lenticular process of the incus (52%). Three of the patients (6%) had residual perforation at the 3
rd month of follow-up. Subjective improvement in hearing was reported by 42% patients. Hearing improvement greater than 10 dB was found in 24 patients (48%). Air-bone gap reduced from 25.16 ± 8.15 dB preoperatively to 12.90 ± 6.20 at 1 year of follow-up. Recurrence was seen in three patients (6%). Conclusion Early intervention by cartilage strengthening of weakened tympanic membrane and ossicular reconstruction not only offers better hearing results, but also prevents progress to active disease., Competing Interests: Conflict of Interests The authors have no conflict of interests to declare., (Fundação Otorrinolaringologia. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commecial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)- Published
- 2022
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32. QcrB in Mycobacterium tuberculosis: The new drug target of antitubercular agents.
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Bahuguna A, Rawat S, and Rawat DS
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- Antitubercular Agents pharmacology, Drug Discovery, Humans, Mycobacterium tuberculosis, Pharmaceutical Preparations, Tuberculosis drug therapy
- Abstract
Drug-resistance in mycobacterial infections is a major global health problem that leads to high mortality and socioeconomic pressure in developing countries around the world. From finding new targets to discovering novel chemical scaffolds, there is an urgent need for the development of better approaches for the cure of tuberculosis. Recently, energy metabolism in mycobacteria, particularly the oxidative phosphorylation pathway of cellular respiration, has emerged as a novel target pathway in drug discovery. New classes of antibacterials which target oxidative phosphorylation pathway either by interacting with a protein or any step in the pathway of oxidative phosphorylation can combat dormant mycobacterial infections leading to shortening of tuberculosis chemotherapy. Adenosine triphosphate synthase is one such recently discovered target of the newly approved antitubercular drug bedaquiline. Cytochrome bcc is another new target of the antitubercular drug candidate Q203, currently in phase II clinical trial. Research suggests that b subunit of cytochrome bcc, QcrB, is the target of Q203. The review article describes the structure, function, and importance of targeting QcrB throwing light on all chemical classes of QcrB inhibitors discovered to date. An understanding of the structure and function of validated targets and their inhibitors would enable the development of new chemical entities., (© 2021 Wiley Periodicals LLC.)
- Published
- 2021
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33. Monocarbonyl curcuminoids as antituberculosis agents with their moderate in-vitro metabolic stability on human liver microsomes.
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Gagandeep, Singh M, Kidawi S, Das US, Velpandian T, Singh R, and Rawat DS
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- Humans, Microbial Sensitivity Tests, Antitubercular Agents pharmacokinetics, Antitubercular Agents pharmacology, Diarylheptanoids pharmacokinetics, Diarylheptanoids pharmacology, Microsomes, Liver metabolism, Mycobacterium tuberculosis growth & development
- Abstract
Tuberculosis, an airborne infectious disease, results in a high morbidity and mortality rate. The continuous emergence of TB resistance strains including MDR (multidrug-resistant tuberculosis), XDR (extensive drug-resistant tuberculosis), and especially TDR (totally drug-resistant tuberculosis) is a major public health threat and has intensified the need to develop new antitubercular agents. A natural product, curcumin, possesses diverse biological activities but suffers due to a lack of water solubility and bioavailability. To overcome these limitations, a series of 17 water-soluble monocarbonyl curcuminoids was synthesized and evaluated for antimycobacterial activity. All compounds exhibited good to moderate anti-TB activity with MIC
99 in the range of 3.12-25.0 µM, out of which 7c and 7p were found the most potent compounds with MIC99 in the range of 3.12-6.25 µM. Furthermore, these compounds were observed to be nonhaemolytic, nontoxic, and stable under both physiological as well as reducing conditions. In-vitro metabolic stability data of the representative compound 7p with the human liver microsome revealed that these compounds possess a moderate metabolism with a half-life of 1.2 h and an intrinsic clearance of 1.12 ml/h/mg., (© 2021 Wiley Periodicals LLC.)- Published
- 2021
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34. Barbiturate derivatives for managing multifaceted oncogenic pathways: A mini review.
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Prasher P, Sharma M, Singh SP, and Rawat DS
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- Aminopeptidases metabolism, Apoptosis drug effects, Histone Deacetylases metabolism, Humans, Matrix Metalloproteinases metabolism, Neoplasms enzymology, Xanthine Oxidase metabolism, Antineoplastic Agents pharmacology, Barbiturates pharmacology, Neoplasms drug therapy
- Abstract
Development and progression of metastasis comprises synchronized erroneous expressions of several composite pathways, which are difficult to manage simultaneously with the representative anticancer molecules. The emergence of the drug resistance and the complex interplay between these pathways further potentiates cancer related complexities. Barbiturates and their derivatives present a commendable anticancer profile by attenuating the cancer manifesting metabolic and enzymatic pathways including, but not limited to matrix metalloproteinases, xanthine oxidase, amino peptidases, histone deacetylases, and Ras/mitogen-activated protein kinase. The derivatization and conjugation of barbiturates with pharmacophores delivers a suitable hybrid profile in containing the anomalous expression of these pathways. The present report presents a succinct collation of the barbiturates and their derivatives in managing the various cancer causing pathways., (© 2020 Wiley Periodicals LLC.)
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- 2021
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35. Site-directed mutagenesis in the P-domain of calreticulin transacylase identifies Lys-207 as the active site residue.
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Joshi R, Singh P, Sharma NK, Ponnan P, Saluja D, Gambhir JK, Rawat DS, Parmar VS, Dwarakanath BS, Prasad AK, and Raj HG
- Abstract
In silico-docking studies from previous work have suggested that Lys-206 and lys-207 of calreticulin (CR) play a pivotal key role in its well-established transacetylation activity. To experimentally validate this prediction, we introduced three mutations at lysine residues of P-domain of CR: K → A, P
mu t-1 (K -206, -209), Pmut -2 (K -206, -207) and Pmu t-3 (K -207, -209) and analyzed their immunoreactivity and acetylation potential. The clones of wild-type P-domain ( Pwt ) and three mutated P-domain ( Pmut -1 , Pmu t-2 and Pmut -3 ) were expressed in pTrcHis C vector and the recombinant Pwt , Pmut-1 , Pmut-2 and Pmut-3 proteins were purified by Ni-NTA affinity chromatography. Screening of the transacylase activity (TAase) by the Glutathione S Transferase (GST) assay revealed that the TAase activity was associated with the Pwt and Pmut-1 while Pmut-2 and Pmut-3 did not show any activity. The immune-reactivity to anti-lysine antibody was also retained only by the Pmut-1 in which the Lys-207 was intact. Retention of the TAase activity and immunoreactivity of Pmut -1 with mutations introduced at Lys-206, Lys-209, while its loss with a mutation at Lys-207 residue indicated that lysine-207 of P-domain constitutes the active site residue controlling TAase activity., Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-021-02659-1., Competing Interests: Conflicts of interestAll authors consent to this submission and declare no conflicts of interest., (© King Abdulaziz City for Science and Technology 2021.)- Published
- 2021
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36. 3D QSAR studies on amphiphilic indoles for antimycobacterial activity.
- Author
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Bahuguna A, Bharatam PV, and Rawat DS
- Subjects
- Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Indoles chemistry, Indoles pharmacology, Mycobacterium bovis growth & development
- Abstract
A persistent infection prolongs treatment duration and also enhances the chance of resistance development against antibiotics. Recently, a class of amphiphilic indole derivatives was discovered exhibiting bactericidal activity against both growing and nongrowing Mycobacterium bovis BCG (M. bovis BCG). These antibacterials are suggested to disturb the integrity and functioning of the cell membrane, a property that can help eradicate persistent organisms. This study article describes field-based three-dimensional quantitative structure-activity relationship (3D-QSAR) studies of 79 amphiphilic indole derivatives. The aim of this QSAR study is to optimize this class of compounds for the development of more potent antimycobacterial agents. The results obtained indicate that steric interactions are crucial for antimycobacterial activity, while hydrogen bond donor groups participate negligibly in activity. The derived 3D-QSAR models showed acceptable r
2 (0.91) and q2 (0.91) with a root mean squared error (RMSE) of 0.08. The models were cross-validated using the leave-one-out method. Applying the same QSAR model to another congeneric series of amphiphilic indoles externally validated the QSAR model. The model could appreciably predict the activity (pMIC50 ) of this congeneric series of amphiphilic indoles, with an RMSE of 0.49, indicating the robustness of the model and its efficiency in predicting the potentially active compounds., (© 2020 Wiley Periodicals LLC.)- Published
- 2021
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37. Synthesis of novel monocarbonyl curcuminoids, evaluation of their efficacy against MRSA, including ex vivo infection model and their mechanistic studies.
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Gagandeep, Kumar P, Kandi SK, Mukhopadhyay K, and Rawat DS
- Subjects
- 3T3 Cells, Animals, Anti-Bacterial Agents chemistry, Chemistry Techniques, Synthetic, Diarylheptanoids chemistry, Methicillin-Resistant Staphylococcus aureus physiology, Mice, Microbial Viability drug effects, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents pharmacology, Diarylheptanoids chemical synthesis, Diarylheptanoids pharmacology, Methicillin-Resistant Staphylococcus aureus drug effects
- Abstract
In continuation of our effort to improve the physiological stability and the antibacterial activity of curcuminoids against drug-resistant bacteria, a series of novel monocarbonyl curcuminoids were synthesized and screened for antibacterial activity against S. aureus and E. coli strains. These curcuminoids showed potent antibacterial activity against both methicillin-sensitive and methicillin-resistant strains of S. aureus with MIC values 2-8 and 4-16 μg/mL, respectively. They also exhibited moderate potency against E. coli strains. The four most active curcuminoids (7d, 7i, 7m, and 7p) were on further investigation found to be very stable under physiological conditions, non-hemolytic, and non-toxic toward mammalian cells up to 150 μg/mL concentration. Mechanistic studies revealed that these curcuminoids displayed potent bactericidal activity by targeting cell membranes. Further, in an ex vivo mammalian co-culture infection model study, remarkably, the curcuminoids 7i and 7p were able to clear the internalized bacteria in mammalian cells and the activity was found to be superior to conventional antibiotics such as vancomycin and linezolid. Therefore, the present study affords us water-soluble, stable, non-toxic curcuminoids that may serve as lead molecules for development as antibacterial agents against MRSA infections., Competing Interests: Declaration of competing interest Authors declare no conflict of interest., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)
- Published
- 2020
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38. Development of Magnesium Oxide-Silver Hybrid Nanocatalysts for Synergistic Carbon Dioxide Activation to Afford Esters and Heterocycles at Ambient Pressure.
- Author
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Gulati U, Rajesh UC, Rawat DS, and Zaleski JM
- Abstract
Multi-metallic hybrid nancatalysts consisting of a porous metal oxide host and metal satellite guests serve as a scaffold for multi-step transformations of divergent and energy-challenging substrates. Here we have developed a 3D porous MgO framework (Lewis basic host) with Ag
0 nanoparticles (noble metal guest) for ambient pressure activation and insertion of CO2 into unsaturated alkyne substrates. The hybrid MgO@Ag-x (x = 2, 5, 7, 8 at % Ag) catalysts are synthesized by impregnating Ag+ ions in porous MgO cubes followed by reduction using NaBH4 . Morphological (SEM, TEM, EDX mapping) and structural (PXRD, XPS) characterization reveal that the micron-sized hybrid cubes derive from self-assembly of ~100 nm (edge length) MgO cubes decorated with ~ 5 to 25 nm Ag0 NPs. Detailed XPS analysis illustrates Ag0 is present in two forms, <10 nm NPs and ~25 nm aggregates. The MgO@Ag-7 catalyst is effective for inserting CO2 into aryl alkynes followed by SN 2 coupling with allylic chlorides to afford a wide range of ester and lactone heterocycles in excellent yields (61-93%) and with low E-factor (2.8). The proposed mechanism suggests a CO2 capture and substrate assembly role for 3D porous MgO while Ag0 performs the key activation of alkyne and CO2 insertion steps. The catalyst is recyclable (5x) with no significant loss of product yield. Overall, these results demonstrate viable approaches to hybrid catalyst development for challenging conversions such as CO2 utilization in a green and sustainable manner., Competing Interests: Conflicts of interest The authors declare no competing financial interests.- Published
- 2020
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39. NSC 18725, a Pyrazole Derivative Inhibits Growth of Intracellular Mycobacterium tuberculosis by Induction of Autophagy.
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Arora G, Gagandeep, Behura A, Gosain TP, Shaliwal RP, Kidwai S, Singh P, Kandi SK, Dhiman R, Rawat DS, and Singh R
- Abstract
The increasing incident rates of drug-resistant tuberculosis (DR-TB) is a global health concern and has been further complicated by the emergence of extensive and total drug-resistant strains. Identification of new chemical entities which are compatible with first-line TB drugs, possess activity against DR-, and metabolically less active bacteria is required to tackle this epidemic. Here, we have performed phenotypic screening of a small molecule library against Mycobacterium bovis BCG and identified 24 scaffolds that exhibited MIC
99 values of at least 2.5 μM. The most potent small molecule identified in our study was a nitroso containing pyrazole derivative, NSC 18725. We observed a significant reduction in viable bacilli load of starved Mycobacterium tuberculosis upon exposure to NSC 18725. The action of NSC 18725 was "synergistic" with isoniazid (INH) and "additive" with other drugs in our checkerboard assays. Structure-activity relationship (SAR) studies of the parent compound revealed that pyrazole derivatives without a functional group at fourth position lacked anti-mycobacterial activity in vitro . The derivative with para -chlorophenyl substitution at the first position of the pyrazole ring was the most active scaffold. We also demonstrate that NSC 18725 is able to induce autophagy in differentiated THP-1 macrophages. The induction of autophagy by NSC 18725 is the major mechanism for the killing of intracellular slow and fast-growing mycobacteria. Taken together, these observations support the identification of NSC 18725 as an antimycobacterial compound, which synergizes with INH, is active against non-replicative mycobacteria and induces autophagy in macrophages., (Copyright © 2020 Arora, Gagandeep, Behura, Gosain, Shaliwal, Kidwai, Singh, Kandi, Dhiman, Rawat and Singh.)- Published
- 2020
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40. An overview of new antitubercular drugs, drug candidates, and their targets.
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Bahuguna A and Rawat DS
- Subjects
- Animals, Antitubercular Agents chemistry, Clinical Trials as Topic, Drug Approval, Humans, Structure-Activity Relationship, Antitubercular Agents pharmacology, Drug Evaluation, Preclinical, Molecular Targeted Therapy
- Abstract
The causative agent of tuberculosis (TB), Mycobacterium tuberculosis and more recently totally drug-resistant strains of M. tuberculosis, display unique mechanisms to survive in the host. A four-drug treatment regimen was introduced 40 years ago but the emergence of multidrug-resistance and more recently TDR necessitates the identification of new targets and drugs for the cure of M. tuberculosis infection. The current efforts in the drug development process are insufficient to completely eradicate the TB epidemic. For almost five decades the TB drug development process remained stagnant. The last 10 years have made sudden progress giving some new and highly promising drugs including bedaquiline, delamanid, and pretomanid. Many of the candidates are repurposed compounds, which were developed to treat other infections but later, exhibited anti-TB properties also. Each class of drug has a specific target and a definite mode of action. These targets are either involved in cell wall biosynthesis, protein synthesis, DNA/RNA synthesis, or metabolism. This review discusses recent progress in the discovery of newly developed and Food and Drug Administration approved drugs as well as repurposed drugs, their targets, mode of action, drug-target interactions, and their structure-activity relationship., (© 2019 Wiley Periodicals, Inc.)
- Published
- 2020
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41. Post-operative Sensorineural Hearing Loss After Middle Ear Surgery.
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Sehra R, Rawat DS, Aseri Y, Tailor M, Chaudhary VK, Singh BK, and Verma PC
- Abstract
Chronic suppurative otitis media is managed by tympanomastoid surgery often requires mastoid drilling. Sometimes patients develop sensorineural hearing loss after middle ear surgery. Objective of the study was to compare pre and post operative bone conduction thresholds after middle ear surgeries. The study was conducted on 90 patients who had undergone middle ear surgeries, 30 patients of tympanoplasty (group I), modified intact canal wall mastoidectomy and tympanoplasty type-I (group II) and modified radical mastoidectomy (group III) each ware included. Demographic and clinical data were reviewed. Duration of surgery, ossicular and middle ear status and drilling time noted. Pre operative and post operative (after 3-4 months) bone conduction thresholds were compared statistically. A value of p < 0.05 was considered statistical significant. The average pre-operative hearing loss of study group was 43.78 ± 14.22 dB. Though postoperatively mean air conduction threshold improved to 36.07 ± 13.05 dB, six patients presented with deterioration of hearing. Mastoidectomy has been performed in all six. Post-operative worsening of bone conduction was seen in three patients (13.75-21.5 dB), one patient of group II and two patients of group III developed postoperative worsening of bone conduction thresholds. Significant hearing losses may occur after tympanomastoid surgery in few patients. While we are evaluating the results besides reporting average results such individual patient should be identified., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interests., (© Association of Otolaryngologists of India 2018.)
- Published
- 2019
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42. Post Parotidectomy Quality of Life in Patients with Benign Parotid Neoplasm: A Prospective Study.
- Author
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Chaudhary VK, Rawat DS, Tailor M, Verma PC, Aseri Y, and Singh BK
- Abstract
Parotid tumours are not uncommon. The management is surgical for benign and malignant parotid neoplasm. Due to the location of parotid gland and its intricate relationship with facial nerve, cosmetic and functional outcomes after parotid surgery are extremely important. Objectives of the study were to analyse facial nerve functions with emphasis on the quality of life of patients undergoing surgery for parotid neoplasm. A prospective study was conducted on patients presented with parotid neoplasm and undergone parotid surgery. Patient with malignant neoplasm were excluded. 30 patients with benign parotid neoplasm in final histopathology were included in the study. Post operative assessment of facial nerve was done using postparotidectomy facial nerve grading system. Symptom-specific QOL was assessed with the parotidectomy outcome inventory-8. Aesthetic outcome was evaluated with an ordinal scale. Posterior belly of digastric muscle and tragal pointer were the commonest landmark used for facial nerve identification. Temporary facial nerve dysfunction was present in six (20%) patients with marginal mandibular branch most commonly involved. 96% of the female patients and 91% of the male patients rated the cosmetic result as good or very good. A statistically significant difference is noted between superficial parotidectomy and total Parotidectomy for cosmetic outcome and sensory impairment. We noted that changed appearance due to resection of the parotid gland and scar and sensory impairment in the area affect the quality of life of patients and such affect are more after total conservative parotidectomy., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Otolaryngologists of India 2018.)
- Published
- 2019
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43. Numerical Investigation of Turbulence in Abdominal Aortic Aneurysms.
- Author
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Rawat DS, Pourquie M, and Poelma C
- Abstract
Computational fluid dynamics (CFD) is a powerful method to investigate aneurysms. The primary focus of most investigations has been to compute various hemodynamic parameters to assess the risk posed by an aneurysm. Despite the occurrence of transitional flow in aneurysms, turbulence has not received much attention. In this article, we investigate turbulence in the context of abdominal aortic aneurysms (AAA). Since the clinical practice is to diagnose an AAA on the basis of its size, hypothetical axisymmetric geometries of various sizes are constructed. In general, just after the peak systole, a vortex ring is shed from the expansion region of an AAA. As the ring advects downstream, an azimuthal instability sets in and grows in amplitude thereby destabilizing the ring. The eventual breakdown of the vortex ring into smaller vortices leads to turbulent fluctuations. A residence time study is also done to identify blood recirculation zones, as a recirculation region can lead to degradation of the arterial wall. In some of the geometries simulated, the enhanced local mixing due to turbulence does not allow a recirculation zone to form, whereas in other geometries, turbulence had no effect on them. The location and consequence of a recirculation zone suggest that it could develop into an intraluminal thrombus (ILT). Finally, the possible impact of turbulence on the oscillatory shear index (OSI), a hemodynamic parameter, is explored. To conclude, this study highlights how a small change in the geometric aspects of an AAA can lead to a vastly different flow field., (Copyright © 2019 by ASME.)
- Published
- 2019
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44. Hybridization of Fluoro-amodiaquine (FAQ) with Pyrimidines: Synthesis and Antimalarial Efficacy of FAQ-Pyrimidines.
- Author
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Tripathi M, Taylor D, Khan SI, Tekwani BL, Ponnan P, Das US, Velpandian T, and Rawat DS
- Abstract
To evade the possible toxicity associated with the formation of quinone-imine metabolite in amodiaquine (AQ), the para -hydroxyl group was replaced with a -F atom, and the resulting 4'-fluoro-amodiaquine (FAQ) was hybridized with substituted pyrimidines. The synthesized FAQ-pyrimidines displayed better in vitro potency than chloroquine (CQ) against the resistant P. falciparum strain (Dd2), exhibiting up to 47.3-fold better activity (IC
50 : 4.69 nM) than CQ (IC50 : 222 nM) and 2.8-fold better potency than artesunate (IC50 : 13.0 nM). Twelve compounds exhibited better antiplasmodial activity than CQ against the CQ-sensitive (NF54) strain. Two compounds were evaluated in vivo against a P. berghei -mouse malaria model. Mechanistic heme-binding studies, computational docking studies against Pf -DHFR and in vitro microsomal stability studies were performed for the representative molecules of the series to assess their antimalarial efficacy., Competing Interests: The authors declare no competing financial interest.- Published
- 2019
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45. N-Substituted aminoquinoline-pyrimidine hybrids: Synthesis, in vitro antimalarial activity evaluation and docking studies.
- Author
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Maurya SS, Bahuguna A, Khan SI, Kumar D, Kholiya R, and Rawat DS
- Subjects
- Aminoquinolines chemistry, Animals, Antimalarials pharmacology, Chlorocebus aethiops, Heme metabolism, Molecular Docking Simulation, Plasmodium falciparum drug effects, Pyrimidines chemistry, Vero Cells, Aminoquinolines pharmacology, Antimalarials chemical synthesis, Pyrimidines pharmacology
- Abstract
A series of novel molecular hybrids based on 4-aminoquinoline-pyrimidine were synthesized and examined for their antimalarial activity. Most of the compounds were found to have potent in vitro antimalarial activity against both CQ-sensitive D6 and CQ-resistant W2 strains of P. falciparum. The active compounds have no considerable cytotoxicity against the mammalian VERO cell lines. Twenty three compounds displayed better antimalarial activity against CQ-resistant strain W2 with IC
50 values in the range 0.0189-0.945 μM, when compared with standard drug chloroquine. The best active compound 7d was studied for heme binding so as to find the primary mode of action of these hybrid molecules. Compound 7d was found to form a stable 1:1 complex with hematin as determined by its Job's plot which suggests that heme may be a probable target of these molecules. Docking studies performed with Pf-DHFR exhibited good binding interactions in the active site. The pharmacokinetic properties of some active compounds were also analysed using ADMET prediction., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)- Published
- 2019
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46. Synthesis, antiamoebic activity and docking studies of metronidazole-triazole-styryl hybrids.
- Author
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Negi B, Poonan P, Ansari MF, Kumar D, Aggarwal S, Singh R, Azam A, and Rawat DS
- Subjects
- Antiprotozoal Agents chemical synthesis, Antiprotozoal Agents chemistry, Dose-Response Relationship, Drug, Entamoeba histolytica enzymology, Enzyme Inhibitors chemical synthesis, Enzyme Inhibitors chemistry, Metronidazole chemistry, Molecular Docking Simulation, Molecular Structure, Parasitic Sensitivity Tests, Structure-Activity Relationship, Styrene chemistry, Thioredoxin-Disulfide Reductase antagonists & inhibitors, Thioredoxin-Disulfide Reductase metabolism, Triazoles chemistry, Antiprotozoal Agents pharmacology, Entamoeba histolytica drug effects, Enzyme Inhibitors pharmacology, Metronidazole pharmacology, Styrene pharmacology, Triazoles pharmacology
- Abstract
A series of 22 novel metronidazole-triazole-styryl hybrids were synthesized and evaluated for their in vitro antiamoebic activity against HM1: IMSS strain of Entamoeba histolytica. Some of the hybrids were found to be more active (IC
50 = 0.12-0.35 μM) than the reference drug metronidazole (IC50 = 1.79 μM). The most active compounds were found to be non-toxic (up to 50 μM) against the Vero cells showing a good safety profile of these hybrids. The docking and ADMET studies were also conducted to investigate the probable mode of action. Docking studies showed significant binding affinity in the active site of E. histolytica thioredoxin reductase (EhTrR) protein., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)- Published
- 2018
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47. Expression of p53, epidermal growth factor receptor, c-erbB2 in oral leukoplakias and oral squamous cell carcinomas.
- Author
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Singla S, Singla G, Zaheer S, Rawat DS, and Mandal AK
- Subjects
- Adult, Carcinoma, Squamous Cell pathology, Case-Control Studies, Female, Humans, Immunohistochemistry, Leukoplakia, Oral pathology, Male, Middle Aged, Mouth Neoplasms pathology, Biomarkers, Tumor, Carcinoma, Squamous Cell metabolism, ErbB Receptors metabolism, Gene Expression, Leukoplakia, Oral metabolism, Mouth Neoplasms metabolism, Receptor, ErbB-2 metabolism, Tumor Suppressor Protein p53 metabolism
- Abstract
Background: Oral cancer is a leading cause of cancer in India and contributes to 12% deaths worldwide. The identification of high-risk oral premalignant lesions such as leukoplakia and intervention at premalignant stages could result in significant loss of mortality and morbidity among these patients. The most frequently observed genetic aberrations in these lesions are of mutations in p53, c-erbB2, and epidermal growth factor receptor (EGFR). No specific tumor markers have been identified consistently in oral leukoplakias and the available studies show wide variations in their expression., Materials and Methods: A total of eighty cases were taken up for study which included forty cases of leukoplakia and forty cases of squamous cell carcinomas (SCCs)., Results: There was a significant correlation between the expression of markers p53 and EGFR in leukoplakia and SCC. The expression of p53 was correlated between leukoplakia, SCC, and control and was found to be significant (P ≤ 0.001). Similarly, EGFR expression was significant (P ≤ 0.001) between cases of leukoplakia, SCCs, and controls. c-erbB2 was found to be negative though cytoplasmic positivity was observed in a few cases. Similarly, in SCCs, it was observed that lesser the differentiation, more is the expression of both p53 and EGFR. Similarly, a definite correlation was observed between p53 and EGFR (P ≤ 0.001) but not with c-erbB2 (P ≤ 1.000)., Conclusion: Thus, the author concludes that p53 and EGFR are useful biomarkers for the diagnosis of leukoplakia and their risk of malignant transformation., Competing Interests: There are no conflicts of interest.
- Published
- 2018
- Full Text
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48. N-Piperonyl substitution on aminoquinoline-pyrimidine hybrids: Effect on the antiplasmodial potency.
- Author
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Kholiya R, Khan SI, Bahuguna A, Tripathi M, and Rawat DS
- Subjects
- Aminoquinolines chemistry, Animals, Antimalarials chemical synthesis, Antimalarials chemistry, Chlorocebus aethiops, Dose-Response Relationship, Drug, Models, Molecular, Molecular Structure, Parasitic Sensitivity Tests, Pyrimidines chemistry, Structure-Activity Relationship, Vero Cells, Aminoquinolines pharmacology, Antimalarials pharmacology, Plasmodium falciparum drug effects, Pyrimidines pharmacology
- Abstract
A series of 4-aminoquinoline-piperonyl-pyrimidine hybrids were synthesized with the aim of identifying compounds with enhanced antimalarial activity. All the synthesized molecules were evaluated in vitro against cultured Plasmodium falciparum W2 and D6 strains and exhibited potent antiplasmodial activities with IC
50 values in the range of 0.02-5.16 μM. Out of the 22 synthesised hybrids, 12 were found to be better (up to eight-fold more active) than chloroquine (CQ), particularly against the CQ-resistant W2 strain of P. falciparum with no significant cytotoxicity towards the mammalian cells. Mechanistic studies reveal that these compounds bind with heme and computational docking studies showed good docking interactions within the active site of Pf-DHFR., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)- Published
- 2017
- Full Text
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49. Chemoselective Hydrazine-mediated Transfer Hydrogenation of Nitroarenes by Co 3 O 4 Nanoparticles Immobilized on an Al/Si-mixed Oxide Support.
- Author
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Reddy PL, Tripathi M, Arundhathi R, and Rawat DS
- Abstract
Cobalt oxide nanoparticles (size 2 to 3.5 nm) were successfully impregnated on an alumina-silica (mixed oxide) support through an experimentally viable and easily reproducible protocol. The prepared material was well characterized by XRD, HR-TEM, BET surface area, EDX and XPS analyses. Porous alumina-silica having a high surface area served as a protective heterogeneous support on which the well-dispersed Co
3 O4 nanoparticles served as an active catalytic species for the hydrazine-mediated transfer hydrogenation of nitroarenes. About 2 mol % of the active catalyst in ethanol at 60 °C was adequate for a successful conversion. Moreover, transfer hydrogenation of nitroarenes by the catalyst was found to take place chemoselectively in the presence of other labile functional groups such as halide, alkene, nitrile, carbonyl, and ester. This inexpensive catalyst was also able to catalyze the reaction on a gram scale reaction and found to be robust and recyclable up to eight runs., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2017
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50. Synthesis, antimalarial activity, heme binding and docking studies of N-substituted 4-aminoquinoline-pyrimidine molecular hybrids.
- Author
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Maurya SS, Khan SI, Bahuguna A, Kumar D, and Rawat DS
- Subjects
- Aminoquinolines pharmacology, Animals, Antimalarials chemical synthesis, Antimalarials metabolism, Binding Sites, Cell Line, Humans, Molecular Docking Simulation, Multienzyme Complexes metabolism, Pyrimidines pharmacology, Structure-Activity Relationship, Tetrahydrofolate Dehydrogenase metabolism, Thymidylate Synthase metabolism, Aminoquinolines chemistry, Antimalarials pharmacology, Heme metabolism, Plasmodium falciparum drug effects, Pyrimidines chemistry
- Abstract
A series of novel N-substituted 4-aminoquinoline-pyrimidine hybrids have been synthesized via simple and economic route and evaluated for their antimalarial activity. Most compounds showed potent antimalarial activity against both CQ-sensitive and CQ-resistant strains with high selectivity index. All the compounds were found to be non-toxic to the mammalian cell lines. The most active compound 7b was analysed for heme binding activity using UV-spectrophotometer. Compound was found to interact with heme and a complex formation between compound and heme in a 1:1 stoichiometry ratio was determined using job plots. The interaction of these hybrids was also investigated by the molecular docking studies in the binding site of wild type Pf-DHFR-TS and quadruple mutant Pf-DHFR-TS. The pharmacokinetic property analysis of best active compounds was also studied by ADMET prediction., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
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