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1.
Vaccine ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38981743

ABSTRACT

Numerous vaccine candidates have emerged in the fight against SARS-CoV-2, yet the challenges posed by viral evolution and the evasion of vaccine-induced immunity persist. The development of broadly protective vaccines is essential in countering the threat posed by variants of concern (VoC) capable of eluding existing vaccine defenses. Among the diverse SARS-CoV-2 vaccine candidates, detailed characterization of those based on the expression of the entire spike protein in mammalian cells have been limited. In our study, we engineered a recombinant prefusion-stabilized trimeric spike protein antigen, IMT-CVAX, encoded by the IMT-C20 gene. This antigen was expressed utilizing a suspension mammalian cell line (CHO-S). The establishment of a stable cell line expressing IMT-CVAX involved the integration of the gene into the CHO genome, followed by the expression, purification, and characterization of the protein. To gauge the vaccine potential of adjuvanted IMT-CVAX, we conducted assessments in small animals. Analyses of blood collected from immunized animals included measurements of anti-spike IgG, SARS-CoV-2 neutralization, and responses from GC-B and Tfh cells. Furthermore, the protective efficacy of IMT-CVAX was evaluated using a Hamster challenge model. Our findings indicate that adjuvanted IMT-CVAX elicits an excellent immune response in both mice and hamsters. Notably, sera from animals immunized with IMT-CVAX effectively neutralize a diverse range of SARS-CoV-2 variants. Moreover, IMT-CVAX immunization conferred complete protection to hamsters against SARS-CoV-2 infection. In hACE2 transgenic mice, IMT-CVAX vaccination induced a robust response from GC-B and Tfh cells. Based on our preclinical model assessments, adjuvanted IMT-CVAX emerges as a highly efficacious vaccine candidate. This protein-subunit-based vaccine exhibits promise for clinical development, offering an affordable solution for both primary and heterologous immunization against SARS-CoV-2 variants.

2.
J Org Chem ; 89(4): 2272-2282, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38305185

ABSTRACT

Synthesis of imidazo-fused polyheterocyclic molecular frameworks, viz. imidazo[1,2-a]pyrrolo[3,4-e]pyridines, imidazo[2,1-a]pyrrolo[3,4-c]isoquinolines, and benzo[g]imidazo[1,2-a]quinoline-6,11-diones, has been achieved by the ruthenium(II)-catalyzed [4 + 2] C-H/N-H annulation of 2-alkenyl/2-arylimidazoles with N-substituted maleimides and 1,4-naphthoquinones. The developed protocol is operationally simple, exhibits broad substrate scope with excellent functional group tolerance, and provides the desired products in moderate to good yields. The mechanistic studies suggest that the reaction involves the formation of a C-C bond through Ru-catalyzed C(sp2)-H bond activation followed by intramolecular cyclization.

3.
Chem Commun (Camb) ; 60(3): 344-347, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38078491

ABSTRACT

Synthesis of functionalized benzo[a]phenazines and indazolo[2,3-a]quinolines has been developed through Rh(III)-catalyzed oxidative annulation of 2-arylquinoxalines and 2-aryl-2H-indazoles with allyl alcohols, respectively. The method features a broad substrate scope, excellent functional group tolerance, good to high yields of annulated products, and scaled-up synthesis capability. Based on a preliminary mechanistic investigation, a tentative mechanism of annulation reaction has been proposed.

4.
Org Lett ; 25(8): 1315-1319, 2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36809005

ABSTRACT

A copper(II)-catalyzed cascade synthesis of 1H-pyrrolo[3,4-b]quinoline-1,3(2H)-diones has been achieved from readily available o-amino carbonyl compounds and maleimides. This one-pot cascade strategy involves a copper-catalyzed aza-Michael addition followed by condensation and oxidation to deliver the target molecules. The protocol features a broad substrate scope and excellent functional group tolerance and affords products in moderate to good (44-88%) yields.

5.
Ann Surg ; 277(1): 9-17, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-35170538

ABSTRACT

OBJECTIVE: The aim of this study was to demonstrate the ability of the Versius Surgical System to successfully and safely complete cholecystectomy. BACKGROUND: The system has been developed in-line with surgeon feedback to overcome limitations of conventional laparoscopy to enhance surgeon experience and patient outcomes. Here we present results from the cholecystectomy cohort from a completed early clinical trial, which was designed to broadly align with Stage 2b of the Idea, Development, Exploration, Assessment, Long-term follow-up framework for surgical innovation. METHODS: Procedures were performed between March 2019 and September 2020 by surgical teams consisting of a lead surgeon and operating room (OR) assistants. Male or female patients aged 18 years and over and requiring cholecystectomy were enrolled. The primary endpoint was the rate of unplanned conversion from robot-assisted surgery to conventional laparoscopic or open surgery. Adverse events (AEs) and serious AEs were adjudicated by video review of the surgery and patient study reports by an independent Clinical Expert Committee. RESULTS: Overall, 134/143 (93.7%) cholecystectomies were successfully completed using the device. Of the 9 (6.3%) conversions to another surgical modality, 7 were deemed to be related to the device. A total of 6 serious AEs and 3 AEs occurred in 8 patients (5.6%), resulting in 4 (2.8%) readmissions to hospital within 30 days of surgery and 1 death. CONCLUSIONS: This study demonstrates cholecystectomy performed using the device is as safe and effective as conventional laparoscopy and supports the implementation of the device on a wider scale, pending instrument modifications, in alignment with Idea, Development, Exploration, Assessment, Long-term follow-up Stage 3 (Assessment).


Subject(s)
Cholecystectomy, Laparoscopic , Laparoscopy , Robotics , Adolescent , Adult , Female , Humans , Male , Cholecystectomy/methods , Cholecystectomy, Laparoscopic/methods , Laparoscopy/methods , Prospective Studies , Robotics/methods
6.
Methods Mol Biol ; 2393: 179-206, 2022.
Article in English | MEDLINE | ID: mdl-34837180

ABSTRACT

Tumor development can be indirectly evaluated using features of the tumor microenvironment (TME), such as hemoglobin saturation (HbSat), blood vessel dilation, and formation of new vessels. High values of HbSat and other features of the TME could indicate high metabolic activity and could precede the formation of angiogenic tumors; therefore, changes in HbSat profile can be used as a biomarker for tumor progression. One methodology to evaluate HbSat profile over time, and correlate it with tumor development in vivo in a preclinical model, is through a dorsal skin-fold window chamber. In this chapter, we provide a detailed description of this methodology to evaluate hemoglobin saturation profile and to predict tumor development. We will cover the surgical preparation of the mouse, the installation/maintenance of the dorsal window chamber, and the imaging processing and evaluation to the HbSat profile to predict new development of new tumor areas over time. We included, in this chapter, step by step examples of the imaging processing method to obtain pixel level HbSat values from raw pixels data, the computational method to determine the HbSat profile, and the steps for the classification of the areas into tumor and no-tumor.


Subject(s)
Neoplasms , Animals , Diagnostic Imaging , Hemoglobins , Mice , Oximetry , Rodentia , Tumor Microenvironment
7.
J Org Chem ; 86(23): 17090-17100, 2021 Dec 03.
Article in English | MEDLINE | ID: mdl-34762443

ABSTRACT

A series of indolyl or imidazo[1,2-a]pyridinyl-substituted para-quinone methides (p-QMs) is prepared by a metal-free, TEMPO-mediated cross-dehydrogenative coupling of butylated hydroxytoluene (BHT) with indoles or imidazo[1,2-a]pyridines in good to high yields. Broad substrate scope with respect to indoles and imidazo[1,2-a]pyridines, good functional group tolerance, and acid/base-free conditions are advantageous feature of the developed protocol. The method was amenable for scale-up on the gram scale. Based on control experiments, a reaction mechanism is proposed to describe this transformation.

8.
Org Biomol Chem ; 19(22): 4910-4921, 2021 06 09.
Article in English | MEDLINE | ID: mdl-34008673

ABSTRACT

A condition-based switchable regioselective hydroalkylation of 2-arylindoles with maleimides has been developed. The reaction in the presence of a Ru(ii)-catalyst resulted in hydroalkylation at the ortho-position of the C2-aryl ring via C-H activation whereas the reaction in the absence of the catalyst in TFE resulted in C3-hydroalkylation. Various functional groups both on the indole ring and on the 2-phenyl ring were tolerated and a wide range of hydroalkylated products were obtained in moderate to high (37-88%) yields.

9.
Org Lett ; 23(4): 1373-1377, 2021 Feb 19.
Article in English | MEDLINE | ID: mdl-33539101

ABSTRACT

A simple and highly efficient metal-free method has been developed for hydroxyfluoroalkylation of indoles and imidazo[1,2-a]pyridines via TEMPO-mediated C(sp3)-H and C(sp2)-H bond cross-dehydrogenative coupling of fluorinated alcohols and indoles. The protocol showed broad substrate scope, afforded good yields of hydroxyfluoroalkylated products, and was amenable for scale-up. Mechanistic investigation indicated involvement of the radical pathway.

10.
Org Biomol Chem ; 18(44): 9072-9080, 2020 11 28.
Article in English | MEDLINE | ID: mdl-33125028

ABSTRACT

A simple and straightforward approach has been realized for the direct benzoylation of imidazoheterocycles by oxidative decarboxylation of arylglyoxylic acids in the presence of K2S2O8 as an oxidant. Various functional groups were tolerated on both imidazoheterocycles and arylglyoxylic acids and a wide range of C5-benzoyl-imidazoheterocycles were obtained in good to high yields (50-84%). Radical trapping experiments confirmed the involvement of the radical pathway. The developed protocol is amenable for a scale-up reaction.

11.
Indian J Crit Care Med ; 22(9): 629-631, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30294127

ABSTRACT

OBJECTIVE: The present study was aimed to establish a threshold value for cardiac troponin I (cTnI) for nonacute coronary syndrome (ACS) participants from the local population and also to determine the importance of serial time point estimation of cTnI in acute myocardial infarction (AMI), non-ST-elevated MI (NSTEMI), and unstable angina cases. METHODS: The present study included 194 cases, admitted in ICCU with the complaint of anginal pain; 31 were diagnosed with AMI with typical electrocardiography (ECG) changes; whereas, 48 cases were diagnosed with NSTEMI. The latter group of cases was selected for the time point study of cTnI release at 0-4 h, 6-12 h, 72 h, and 144 h of admission. cTnI levels were assessed using the Abbott ARCHITECT i1000SR system. RESULTS: ACS was clinically ruled out in 98 cases, and cTnI level for them was used to decide cTnI threshold for the non-ACS group. cTnI level was checked in 17 cases of unstable angina. The threshold value of cTnI for non-ACS participants was 0.1 ng/ml and can be considered as cut-off value for the regional population. The data suggested that the peak of cTnI levels in most of the AMI cases reached during 6-12 h. The cTnI levels were lower than 0.1 ng/ml, and no significant change in ECG was noticed in 17 cases of unstable angina. CONCLUSION: The present study suggested that the repeat of cTnI assay after 4-6 h of admission is required if the initial value is <3 ng/ml.

12.
Int J Nanomedicine ; 12: 6437-6459, 2017.
Article in English | MEDLINE | ID: mdl-28919746

ABSTRACT

Bacterial cellulose (BC) is a naturally occurring nanofibrous biomaterial which exhibits unique physical properties and is amenable to chemical modifications. To explore whether this versatile material can be used in the treatment of osteochondral defects (OCD), we developed and characterized novel BC-based nanocomposite scaffolds, for example, BC-hydroxyapatite (BC-HA) and BC-glycosaminoglycans (BC-GAG) that mimic bone and cartilage, respectively. In vitro biocompatibility of BC-HA and BC-GAG scaffolds was established using osteosarcoma cells, human articular chondrocytes, and human adipose-derived mesenchymal stem cells. On subcutaneous implantation, the scaffolds allowed tissue ingrowth and induced no adverse immunological reactions suggesting excellent in vivo biocompatibility. Implantation of acellular bilayered scaffolds in OCD created in rat knees induced progressive regeneration of cartilage tissue, deposition of extracellular matrix, and regeneration of subchondral bone by the host cells. The results of micro-CT revealed that bone mineral density and ratio of bone volume to tissue volume were significantly higher in animals receiving bilayered scaffold as compared to the control animals. To the best of our knowledge, this study proves for the first time, the functional performance of acellular BC-based bilayered scaffolds. Thus, this strategy has great potential for clinical translation and can be used in repair of OCD.


Subject(s)
Biocompatible Materials/chemistry , Chondrocytes/cytology , Nanocomposites/chemistry , Tissue Scaffolds , Acetobacteraceae/chemistry , Animals , Bone Regeneration/physiology , Cartilage/cytology , Cellulose/chemistry , Chondrocytes/chemistry , Disease Models, Animal , Durapatite/chemistry , Glycosaminoglycans/chemistry , Humans , Materials Testing , Mesenchymal Stem Cells/cytology , Rats , Rats, Wistar , Tissue Engineering/methods , Tissue Scaffolds/chemistry
13.
South Asian J Cancer ; 6(2): 47-50, 2017.
Article in English | MEDLINE | ID: mdl-28702403

ABSTRACT

BACKGROUND: The adjuvant short course 9-week trastuzumab combination therapy for human epidermal receptor 2 positive breast cancer patients may often be considered as a cost-effective and safe option and has important implications for the Indian subcontinent as well as other developing countries. However, such regimens of shorter duration trastuzumab therapy like FinHer, offered in view of economic constraints, may not be able to achieve globally comparable cure rates in early breast cancer especially with high-risk women with more than 3 lymph node positive. METHODS AND MATERIAL: Outcome of 21 patients with HER2 positive breast cancer was treated with short course trastuzumab combination chemotherapy in the adjuvant setting was studied. RESULTS: Out of 21 patients 15 are alive and disease free with a follow up of up to 73 months (median follow up 42 months).

14.
Phytother Res ; 30(3): 412-7, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26648323

ABSTRACT

The present study was carried out to evaluate anti-Helicobacter pylori and its associated urease activity of labdane diterpenoids isolated from Andrographis paniculata. A molecular docking analysis was performed by using ArgusLab 4.0.1 software. The results obtained indicate that compound A possesses strong inhibition to H. pylori, 28 ± 2.98 (minimum inhibitory concentration, 9 µg/mL), and its urease, 85.54 ± 2.62% (IC50 , 20.2 µg/mL). Compounds B, C, and D also showed moderate inhibition to H. pylori and its urease. The obtained results were in agreement with the molecular docking analysis of compounds. The phytochemicals under investigation were found to be promising antibacterial agents. Moreover, the isolated compounds can be considered as a resource for searching novel anti-H. pylori agents possessing urease inhibition.


Subject(s)
Andrographis/chemistry , Anti-Bacterial Agents/pharmacology , Diterpenes/pharmacology , Helicobacter pylori/drug effects , Plant Extracts/pharmacology , Urease/antagonists & inhibitors , Anti-Bacterial Agents/isolation & purification , Bacterial Proteins/antagonists & inhibitors , Diterpenes/isolation & purification , Helicobacter pylori/enzymology , Helicobacter pylori/growth & development , Microbial Sensitivity Tests , Molecular Docking Simulation , Plant Extracts/chemistry
15.
Indian J Plast Surg ; 49(3): 406-409, 2016.
Article in English | MEDLINE | ID: mdl-28216824

ABSTRACT

Myocardial infarction (MI) following high voltage electric burn is very rare, and its pathogenesis remains controversial. Electrical burns represent only 4% of all burns. Hence, clinical managements have taken a slow pace in developing. The recent guidelines laid down by the cardiology societies include cardiac troponin I (cTnI) as the gold standard marker for the assessment of myocardial damage assessment. Two patients were admitted to our hospital at the different time with the same kind of high voltage electric burn. Both patients had complained with chest discomfort during admission, and cardiac parameter assessment was done for both the patients. cTnI was also measured for both patients, and marked increase in the values was seen within 5 h of onset of myocardial damage and got into normal range within 72 h. Myocardial damage following electric burn needs to be suspected and assessed as early as possible. Hence, cTnI should be the valuable tool to detect the severity of myocardial damage incurred in the electric burn cases.

16.
Asian J Transfus Sci ; 9(2): 129-32, 2015.
Article in English | MEDLINE | ID: mdl-26420929

ABSTRACT

CONTEXT: Bombay blood group although rare is found to be more prevalent in the Western and Southern states of India, believed to be associated with consanguineous marriage. AIMS: To estimate the prevalence of the Bombay blood group (Oh) in the urban population of Puducherry. To find the effect of urbanization on consanguineous marriage and to establish whether consanguinity plays a part in the prevalence of Oh group. To compare Oh group prevalence with that of other neighboring states, where population is not predominantly urban. SETTINGS AND DESIGN: This is a descriptive study in a tertiary care hospital in Puducherry, over a period of 6 years. MATERIALS AND METHODS: All blood samples showing 'O' group were tested with anti-H lectin. Specialized tests like Adsorption Elution Technique, inhibition assay for determination of secretor status were performed on Oh positive cases. Any history of consanguineous marriage was recorded. STATISTICAL ANALYSIS USED: All variables were categorical variable and percentage and proportions were calculated manually. RESULTS: Analysis of the results of 35,497 study subjects showed that the most common group was 'O' group constituting 14,164 (39.90%) of subjects. Only three "Oh" that is, Bombay phenotype (0.008%) were detected. Consanguinity was observed in two cases (66.66%). CONCLUSIONS: This study shows the prevalence of Bombay blood group representing the urban population of Puducherry, to be high (0.008%) and associated with consanguineous marriage (66.66%). Thus, consanguinity is still an important risk factor present, even in an urban population in Southern India.

17.
Colloids Surf B Biointerfaces ; 130: 84-92, 2015 Jun 01.
Article in English | MEDLINE | ID: mdl-25909183

ABSTRACT

Recombinant expression of Capsicum annuum proteinase inhibitors (CanPI-13) and its application via synthetic carrier for the crop protection is the prime objective of our study. Herein, we explored proteinase inhibitor peptide immobilization on silica based nanospheres and rods followed by its pH mediated release in vitro and in vivo. Initial studies suggested silica nanospheres to be a suitable candidate for peptide immobilization. Furthermore, the interactions were characterized biophysically to ascertain their conformational stability and biological activity. Interestingly, bioactive peptide loading at acidic pH on nanospheres was found to be 62% and showed 56% of peptide release at pH 10, simulating gut milieu of the target pest Helicoverpa armigera. Additionally, in vivo study demonstrated significant reduction in insect body mass (158 mg) as compared to the control insects (265 mg) on 8th day after feeding with CanPI-13 based silica nanospheres. The study confirms that peptide immobilized silica nanosphere is capable of affecting overall growth and development of the feeding insects, which is known to hamper fecundity and fertility of the insects. Our study illustrates the utility and development of peptide-nanocarrier based platform in delivering diverse biologically active complexes specific to gut pH of H. armigera.


Subject(s)
Drug Delivery Systems/methods , Glycoproteins/administration & dosage , Nanospheres/chemistry , Plant Proteins/administration & dosage , Silicon Dioxide/chemistry , Amino Acid Sequence , Animals , Biophysical Phenomena , Digestive System/metabolism , Glycoproteins/chemistry , Glycoproteins/metabolism , Hydrogen-Ion Concentration , Immobilized Proteins/administration & dosage , Immobilized Proteins/chemistry , Immobilized Proteins/metabolism , Kinetics , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Molecular Sequence Data , Moths/metabolism , Nanospheres/ultrastructure , Plant Proteins/chemistry , Plant Proteins/metabolism , Sequence Homology, Amino Acid
18.
Chem Commun (Camb) ; 51(40): 8496-9, 2015 May 18.
Article in English | MEDLINE | ID: mdl-25891032

ABSTRACT

We report the synthesis of a trifunctional catalyst containing amine, sulphonic acid and Pd nanoparticle catalytic groups anchored on the pore walls of SBA-15. The catalyst efficiently catalyzes one-pot three-step cascade reactions comprising deacetylation, Henry reaction and hydrogenation, giving up to ∼100% conversion and 92% selectivity to the final product.


Subject(s)
Amines/chemistry , Metal Nanoparticles/chemistry , Palladium/chemistry , Silicon Dioxide/chemistry , Sulfonic Acids/chemistry , Catalysis , Hydrogenation , Metal Nanoparticles/ultrastructure , Microscopy, Electron, Transmission , Porosity
19.
Indian J Pediatr ; 82(7): 629-36, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25257964

ABSTRACT

Acute respiratory distress is one of the most common reason for emergency visits in children under 5 y of age. An accurate understanding of the epidemiology of these diseases, identification of risk factors and etiology is critical for successful treatment and prevention of related mortality. The cause of acute respiratory distress varies in etiology, and hence is amenable to different treatment modalities. Depending on the predominant symptoms and signs, a child presenting to the clinician can be divided into six groups, viz., stridor; cough, fever and difficulty in breathing or fast breathing; wheezing; mediastinal shift with severe respiratory distress; slow or irregular breathing in absence of any pulmonary sign; and respiratory distress with cardiac findings. A detailed history followed by a thorough clinical examination and laboratory evaluation assisted by imaging modalities if indicated, helps to establish the exact cause of respiratory distress in the child. Early recognition and prompt institution of appropriate management or referral can significantly improve the outcome of this illness. This article offers clinicians a brief update on the general management guidelines of respiratory distress in pediatric patients. Specific treatment depends on the exact cause, however croup and acute severe asthma have been discussed in this article.


Subject(s)
Airway Obstruction/diagnosis , Asthma/diagnosis , Croup/diagnosis , Respiratory Distress Syndrome/diagnosis , Adolescent , Airway Obstruction/therapy , Asthma/therapy , Child , Child, Preschool , Croup/therapy , Diagnosis, Differential , Humans , Respiratory Distress Syndrome/therapy
20.
J Med Imaging (Bellingham) ; 1(1): 014503, 2014 Apr.
Article in English | MEDLINE | ID: mdl-26158025

ABSTRACT

Features of the tumor microenvironment (TME), such as hemoglobin saturation (HbSat), can provide valuable information on early development and progression of tumors. HbSat correlates with high metabolism and precedes the formation of angiogenic tumors; therefore, changes in HbSat profile can be used as a biomarker for early cancer detection. In this project, we develop a methodology to evaluate HbSat for forecasting early tumor development in a mouse model. We built a delta ([Formula: see text]) cumulative feature that includes spatial and temporal distribution of HbSat for classifying tumor/normal areas. Using a two-class (normal and tumor) logistic regression, the [Formula: see text] feature successfully forecasts tumor areas in two window chamber mice ([Formula: see text] and 0.85). To assess the performance of the logistic regression-based classifier utilizing the [Formula: see text] feature of each region, we conduct a 10-fold cross-validation analysis (AUC of the [Formula: see text]). These results show that the TME features based on HbSat can be used to evaluate tumor progression and forecast new occurrences of tumor areas.

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