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1.
Adv Biomed Res ; 13: 4, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525391

RESUMO

Background: To determine the superiority of the combination of endoscopic retrograde cholangiopancreatography (ERCP) and digital single-operator cholangioscopy (DSOC) in the same sitting over the individual modality alone in patients with indeterminate biliary strictures. Materials and Methods: A randomized study enrolled 60 adult patients with biliary strictures who were randomized into two groups: ERCP + DSOC and ERCP/DSOC. Histopathologic or cytologic assessment was performed in terms of benign, indeterminate, or malignant nature of the strictures. Procedural adverse events were documented. Accuracy in terms of sensitivity (Sn), specificity (Sp), and predictive value [positive (PPV) and negative (NPV)] were noted. Results: As per final diagnosis, in ERCP/DSOC group, there were 12 (40%) benign cases and 18 (60%) malignant cases, and in group ERCP + DSOC, there were 8 (26.67%) benign cases and 22 (73.33%) malignant cases. ERCP/DSOC labeled 16 (53.33%) patients as benign, 8 (26.67%) as malignant, and 6 (20%) as indeterminate, while ERCP + DSOC labeled 8 (26.67%) as benign, 17 (56.67%) as malignant, and 5 (16.67%) as indeterminate. The Sn, Sp, PPV, and NPV of ERCP/DSOC were 44.4%, 75%, 100%, and 56.25%, and for ERCP + DSOC was 77.27%, 62.50%, 100%, and 62.5%, respectively (P = 0.033). Side effects were statistically similar in both the groups (P > 0.05). Conclusion: To conclude, the combination of ERCP with DSOC is safe and effective with higher diagnostic sensitivity (77.27%) in comparison to standard ERCP or DSOC alone (44.4%) for the diagnosis of biliary strictures.

2.
J Org Chem ; 88(21): 15085-15096, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37847075

RESUMO

In the quest to synthesize high-performing insensitive high-energy density materials (HEDMs), the main challenge is establishing an equilibrium between energy and stability. For this purpose, we explored 4-hydroxy-3,5-dinitropyrazole- and tetrazole-based energetic scaffolds connected via a N-methylene-C bridge. The hydroxy functionality between nitro groups on the pyrazole ring promotes physical stability via inter- and intramolecular hydrogen bonding and contributes to oxygen balance, supporting better energetic performance. Due to two acidic sites (OH and NH) with different reactivities, a series of monocationic and dicationic salts were synthesized, and their overall performance was compared. All compounds synthesized in this study have high physical stability with impact sensitivity >40 J and friction sensitivity >360 N. Monocationic salts were generally found to have better thermal stability with respect to their corresponding dicationic energetic salts, which showed better energetic performance. The salt formation strategy effectively improved the thermal stability of 2 (Td = 168 °C), where most energetic salts have decomposition temperatures higher than 220 °C. All of the compounds were characterized through IR, multinuclear NMR spectroscopy, high-resolution mass spectrometry (HRMS), and elemental analysis. The structure-property relationship was studied using Hirshfeld surface analysis, noncovalent interaction (NCI) analysis, and electrostatic potential studies.

3.
Environ Res ; 228: 115928, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37076032

RESUMO

Heavy metals and plastic pollutants are the two most disastrous challenges to the environment requiring immediate actions. In this work, a techno-commercially feasible approach to address both challenges is presented, where a waste polypropylene (PP) based reversible sensor is produced to selectively detect copper ions (Cu2+) in blood and water from different sources. The waste PP-based sensor was fabricated in the form of an emulsion-templated porous scaffold decorated with benzothiazolinium spiropyran (BTS), which produced a reddish colour upon exposure to Cu2+. The presence of Cu2+ was checked by naked eye, UV-Vis spectroscopy, and DC (Direct Current) probe station by measuring the current where the sensor's performance remained unaffected while analysing blood, water from different sources, and acidic or basic environment. The sensor exhibited 1.3 ppm as the limit of detection value in agreement with the WHO recommendations. The reversible nature of the sensor was determined by cyclic exposure of the sensor towards visible light turning it from coloured to colourless within 5 min and regenerated the sensor for the subsequent analysis. The reversibility of the sensor through exchange between Cu2+- Cu+ was confirmed by XPS analysis. A resettable and multi-readout INHIBIT logic gate was proposed for the sensor using Cu2+ and visible light as the inputs and colour change, reflectance band and current as the output. The cost-effective sensor enabled rapid detection of the presence of Cu2+ in both water and complex biological samples such as blood. While the approach developed in this study provides a unique opportunity to address the environmental burden of plastic waste management, it also allows for the possible valorization of plastics for use in enormous value-added applications.


Assuntos
Sangue , Cobre , Metais Pesados , Polipropilenos , Cobre/química , Íons/análise , Água
4.
Bioorg Med Chem Lett ; 86: 129240, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36931350

RESUMO

Folate receptors (FRs) are known to be over-expressed in several human malignancies and therefore serve as an important target for small radiolabeled folate derivatives for non-invasive imaging of tumor, which is an important tool for future treatment recourse. In the present article, we report the synthesis of a new 99mTc-labeled radiotracer for the aforementioned application following the well-established 99mTc-'4+1' chemistry. Formation of the desired [99mTc]Tc-complex with >95% radiochemical purity was confirmed by radio-HPLC and its structure was ascertained by characterizing a natural rhenium analogue of the said complex. Although the ligand exhibited a weaker affinity towards FRs compared to native folic acid (IC50 8.09 µM vs 29.46 nM), the 99mTc-labeled complex was found to bind folate receptor-positive KB cells with high specificity (∼90%). Similar studies in a folate receptor negative cell line viz. A549 further corroborated the receptor-specificity of the synthesized complex. In vivo studies in KB tumor xenograft showed moderate uptake of ∼2.6% upto 3 h post-injection with high specificity (∼80%). The favorable features observed warrant further screening of the current design towards achieving an improved molecular probe for the said application.


Assuntos
Ácido Fólico , Neoplasias , Humanos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Compostos Radiofarmacêuticos , Proteínas de Transporte/metabolismo , Tecnécio/química
5.
Indian J Otolaryngol Head Neck Surg ; 75(2): 292-298, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36373124

RESUMO

Introduction: The incidence of acquired laryngotracheal stenosis is on rise, being caused usually due to prolonged intubation or trauma. Its management has thus become a common clinical challenge for Otolaryngologists and Head and Neck surgeons. Further, with advances in Critical care medicine, Cardiopulmonary surgery and Neurosurgery, the number of intubation-related laryngotracheal injuries is increasing. Objectives: To assess the outcome of patients who underwent Partial Cricotracheal Resection (PCTR) for subglottic stenosis on basis of pre-defined parameters. Design of Study: This is a prospective study. Materials and Methods: Four patients who came to Ear Nose Throat (ENT) department, All India Institute of Medical Sciences (AIIMS) Patna with complaints of either difficult decannulation or stridor, for which PCTR was planned, were included in the study. Surgical resection was done and all patients were followed up for a minimum of 6 months. Postoperatively certain parameters, such as respiration, voice, difficulty in swallowing, feeding and personal satisfaction, were used to evaluate the patients and analyse the efficacy of the surgery. Results: Three out of four cases came up with complete cure with no dyspnoea, dysphagia, hoarseness of voice. Only one patient could not be extubated and was continued on Ryle's tube for longer duration compared to other patients. Conclusion: PCTR is an effective and reliable procedure for management of laryngotracheal stenosis caused due to trauma.

6.
Materials (Basel) ; 15(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35268954

RESUMO

As a promising candidate in the construction industry, iron-based shape memory alloy (Fe-SMA) has attracted lots of attention in the engineering and metallography communities because of its foreseeable benefits including corrosion resistance, shape recovery capability, excellent plastic deformability, and outstanding fatigue resistance. Pilot applications have proved the feasibility of Fe-SMA as a highly efficient functional material in the construction sector. This paper provides a review of recent developments in research and design practice related to Fe-SMA. The basic mechanical properties are presented and compared with conventional structural steel, and some necessary explanations are given on the metallographic transformation mechanism. Newly emerged applications, such as Fe-SMA-based prestressing/strengthening techniques and seismic-resistant components/devices, are discussed. It is believed that Fe-SMA offers a wide range of applications in the construction industry but there still remains problems to be addressed and areas to be further explored. Some research needs at material-level, component-level, and system-level are highlighted in this paper. With the systematic information provided, this paper not only benefits professionals and researchers who have been working in this area for a long time and wanting to gain an in-depth understanding of the state-of-the-art, but also helps enlighten a wider audience intending to get acquainted with this exciting topic.

7.
Nucl Med Biol ; 93: 1-10, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33212346

RESUMO

INTRODUCTION: Strategic design and synthesis of nanoparticle based preparations could improve diagnostic screening of several cancer types, thereby facilitating better clinical management of the disease. Towards this, the present work aims to develop and evaluate a radioactive technetium-99m (99mTc) labeled gold nanoparticle (NP) preparation modified with folic acid, so as to diagnose folate receptor positive cancers viz. ovarian, breast, etc. METHODS: 11-Bromoundecanoic acid (UA) was synthetically modified both with folic acid and Hydrazinonicotinic acid (HYNIC) chelate at the carboxylic acid end and subsequently converted to thiol functionality at the bromo terminal to yield folic acid-UA-SH and HYNIC-UA-SH ligands respectively. Gold NPs modified with folic acid and HYNIC chelator were obtained on direct addition of folic acid-UA-SH and HYNIC-UA-SH to chloroauric acid in polysorbate 80 solution under reducing conditions. These NPs were then radiolabeled with 99mTc following HYNIC labeling approach. Both the inactive and 99mTc-labeled gold NPs were then tested for their biological efficacy in folate receptor (FR) positive KB cancer cell lines. Also, biodistribution studies of 99mTc-labeled gold NPs were carried in KB tumor xenografts to ascertain the efficacy towards FR in in vivo system. RESULTS: Polysorbate 80 could stabilize the gold NP preparation with average size <10 nm as determined by TEM. Inhibition of [3H]folic acid with functionalized gold nanoparticle revealed affinity towards FR positive KB cell lines with an IC50 ~ 9 µM. Biodistribution studies of 99mTc-labeled gold NP preparation in SCID mice bearing KB tumor showed an uptake of 1.39 ± 0.18%ID/g in tumor and 5.48 ± 0.72%ID/g in kidneys at 3 h post-injection. In vivo distribution in folic acid pre-treated animals could not establish the specificity towards folate receptors. CONCLUSIONS: Biological evaluation of functionalized gold NP showed affinity towards FR positive cancer cell lines. 99mTc-labeled NP exhibited target uptake in both in vitro and in vivo models, but folic acid inhibition could not establish the target specificity. Nevertheless, in vivo pharmacokinetics envisaged in the present design was achieved using the present gold functionalized NP preparation.


Assuntos
Receptores de Folato com Âncoras de GPI/metabolismo , Ouro/química , Imagem Molecular/métodos , Nanoestruturas/química , Tecnécio/química , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Marcação por Isótopo , Camundongos , Tecnécio/farmacocinética , Distribuição Tecidual
8.
J Midlife Health ; 11(4): 200-209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33767560

RESUMO

BACKGROUND: To compare the prevalence of anxiety and depression levels in patients with benign breast disease (BBD) and healthy individuals using Hospital Anxiety and Depression Scale (HADS) and Brief Patient Health Questionnaire (BPHQ). METHODS: This study includes 100 patients who were clinically suspected of having BBDs and were matched against 100 healthy age-matched controls from June 2016 and July 2018. The diagnosis of BBD was established on the basis of ultrasonography, fine needle aspiration cytology, and/or histopathology. For the diagnosis of anxiety and depression, BPHQ was used and the level of anxiety and depression was measured using the HADS. The questionnaire at both prediagnosis and at follow-up assessment after 3 months was done. RESULTS: On comparing anxiety and depression using BPHQ score among cases and controls, both were significantly associated with cases than controls (P < 0.001 and P = 0.0016, respectively). On comparing anxiety and depression using HADS score, there was a significant difference (median) in both anxiety and depression level between cases and controls (P < 0.001 and P < 0.001, respectively). After 3 months of follow-up, there was a significant improvement in anxiety and depression scores by both BPHQ (P = 0.007 and P = 0.0016) and HADS (P < 0.001 and P < 0.001). The 3-month follow-up data showed a significant improvement in BPHQ (depression) score in patients with breast lump and mastalgia (P = 0.001 and P = 0.008). The HADS (anxiety score) showed significant improvement in patients presenting with diseases/aberrations other than fibroadenoma while the HADS (depression) score showed a significant improvement in all except fibroadenosis present either alone or along with fibroadenoma. The HADS (depression) score showed a significant improvement in fibroadenoma, others group, breast lump, and mastalgia (P = 0.040, P = 0.005, P < 0.001, and P = 0.025, respectively). CONCLUSION: Indian female patients who present with BBDs are also affected by anxiety and depression.

9.
Chemistry ; 23(66): 16753-16757, 2017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-29047175

RESUMO

Sodium salts of iodine-rich pyrazole and imidazole with 1-(2-bromoethyl)-5-aminotetrazole are useful precursors for energetic N,N'-ethylene-bridged polyiodoazoles. Compounds 1-3 were characterized with IR, and 1 H and 13 C NMR spectroscopy as well as elemental analyses. The molecular structures of 1 and 2 were confirmed by using single crystal X-ray diffraction. Heats of formation were calculated using Gaussian 03 and detonation properties and biocidal efficiency were calculated with CHEETAH 7. The decomposition products of 1-3 destroy microbes more effectively than some previously reported biocides since the thermal decomposition occurs at below 400 °C without addition of oxidizer or combustion adjuvant.


Assuntos
Etilenos/química , Tetrazóis/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalografia por Raios X , Iodo/química , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho
10.
Natl J Maxillofac Surg ; 4(1): 46-51, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24163552

RESUMO

INTRODUCTION: The replacement of missing anterior teeth presents peculiar challenges to the Prosthodontist. Implants are increasingly gaining favour for the same. The morphology of existing bone in the premaxilla often dictates that implants are placed at angles that are difficult to restore with conventional abutments. However, the angulated abutments might transfer unfavourable forces to the implant or bone, thereby compromising the prognosis of the treatment. Because, it is difficult to assess the generated forces clinically, a finite element analysis was chosen for the present study as it is useful tool in estimating stress distribution in the contact area of the implant with the bone. MATERIALS AND METHODS: In this study, the frontal region of the maxilla was modelled with a cortical layer 1.5 mm thick containing an inner cancellous core. The implant was cylindrical, round ended, with length 13 mm and diameter 4.1 mm. The abutment was modelled as 7 mm in height with a 5 degree occlusal taper. The different abutment angulations used were 0°, 10°, 15° and 20°. The amount of loads used were 100, 125, 150, 175 and 200 N axially, and 50 N in oblique direction, to approximate the kind of loads seen in clinical situations. RESULT: It was seen that, as the abutment angulation changes from 0° to 20° both the compressive as well as tensile stresses increased; but, it is within the tolerance limit of the bone. CONCLUSION: It seems reasonably safe to use angled abutments in anterior implant supported prostheses, in the maxillary arch.

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