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1.
Article in English | MEDLINE | ID: mdl-38874192

ABSTRACT

INTRODUCTION: Locally advanced carcinoma cervix (LACC) is a heterogeneous disease with variable combinations of primary tumour extensions with or without nodal involvement. Metabolic information from 18 fluro-deoxyglucose positron emission tomography combined with contrast-enhanced computerized tomography (FDG PET-CT) may potentially augment treatment decision-making for LACC. This study ascertained FDG-PET CT influence on chemoradiation therapy (CTRT) decisions in LACC. We report oncologic and patient-reported outcome measures (PROMs). METHODS: FDG PET-CT scans were reviewed independently by two nuclear medicine specialists and two radiation oncologists. Pelvic CTRT plan digressions were documented and therapy was adapted accordingly. Pelvis radiation (50 Gy/25#/5 weeks) using tomotherapy with weekly cisplatin was used in node-negative disease. Dose-escalated simultaneous integrated boost (SIB) 60 Gy/25#/5 weeks was delivered to involved pelvic nodes. All received brachytherapy. Post-treatment PET-CT scans were at 6 months. Functional assessment of cancer therapy scores were calculated at baseline, treatment completion, 3 months, 1 year and 3 years. RESULTS: Between November 2015 and January 2018, 85 patients were screened, and 77 consented. Extrapelvic disease was seen in 12 (16%) patients (9 para-aortic nodes, 2 distant metastases and 1 synchronous carcinoma breast); 60 patients were included in the final analysis. Decision changes were seen in 10/77 (13%) screened, 8/60 (13%) included and 32 (53.3%) received SIB. Post-treatment, 27 (45%) had grade 2 GI/GU/GYN toxicity, one (2%) had grade 3 GI and five (8.3%) had grade 3 neutropenia. At median overall survival of 54.2 months (95% CI 52.8-58.3), 5-year local failure, pelvic nodal and para-aortic nodal-free survival were 86.8% (95% CI 78.0-96.6), 85.2% (95% CI 76.1-95.3) and 85.2% (95% CI 76.2-95.4). Functional assessment of cancer therapy trial outcome index (FACT TOI) improved by 10.43 at 3 months with no further decline. Grade 3 toxicity was noted for abdominal pain in one (1.7%), cystitis in four (6.7%) and lymphoedema in one (1.7%) at 5 years. CONCLUSION: PET-CT resulted in major decision changes in 13%. PET-adapted CTRT was associated with acceptable toxicity, encouraging long-term survival and improvement in PROMS.

2.
ACS Appl Mater Interfaces ; 14(48): 54073-54080, 2022 Dec 07.
Article in English | MEDLINE | ID: mdl-36401833

ABSTRACT

The development of nanoscale composites with hierarchical architecture and complex anisotropies enables the fabrication of new classes of devices. Stretchable strain sensors have been developed in the past for applications in various fields such as wearable electronics and soft robotics, yet the sensing capacities of most of these sensors are independent of the direction of deformation. In the present work, we report on the preparation of a direction-sensitive strain sensor using the anisotropic optical properties of a monolayer of oriented plasmonic 1D nano-objects. Grazing incidence spraying (GIS) is used for depositing a monolayer of in-plane aligned silver nanowires with a controlled density on a deformable and transparent substrate. Using the selective excitation of transverse and longitudinal localized plasmon resonance modes of silver nanowires by polarized UV-visible-NIR spectroscopy, we show that the macroscopic anisotropic properties of the monolayer upon stretching are highly dependent on the stretching direction and light polarization. Measuring the polarized optical properties of the anisotropic thin films upon stretching thus allow for retrieving both the local strain and the direction of the deformation using a simple model.

3.
Mater Horiz ; 9(5): 1468-1478, 2022 05 10.
Article in English | MEDLINE | ID: mdl-35244665

ABSTRACT

Self-powered tactile module-based electronic skins incorporating triboelectric nanogenerator (TENG) appears to be a worthwhile alternative for smart monitoring devices in terms of sustainable energy harvesting. On top of it, ultra-stretchability and detection sensitivity are imperative to mimic human skin. We report, for the first time, a metal-free single electrode TENG-based self-powered tactile module comprising of microwells (diameters 2 µm and 200 nm, respectively) on fluoroelastomer (FKM) and laser induced graphene (LIG) electrodes by in situ simultaneous transfer printing method. Direct imprinting of both the active surface and LIG electrode on a tribonegative FKM has not been attempted before. The resulting triboelectric module exhibits impressive maximum power density of 715 mW m-2, open circuit voltage and maximum output current of 148 V and 9.6 µA respectively for a matching load of 10 MΩ. Moreover, the TENG unit is very robust and sustained high electrical output even at 200% elongation. A dielectric-to-dielectric TENG-based tactile sensor is also constructed using FKM (negative tribolayer) and TiO2 deposited micropatterned PDMS. Resulting tribo-sensor demonstrates remarkable motion and force sensitivity. It can also distinguish subtle human contact force that can simulate skin with high sensitivity and therefore, can be utilized for potential e-skin/bionic skin applications in health and human-machine interfaces.


Subject(s)
Nanotechnology , Wearable Electronic Devices , Elasticity , Electrodes , Humans , Printing, Three-Dimensional
5.
Ecancermedicalscience ; 15: 1290, 2021.
Article in English | MEDLINE | ID: mdl-34824613

ABSTRACT

BACKGROUND: Ovarian germ cell tumours constitute a heterogeneous group of neoplasm with malignant potential being seen in 5% of cases. There is limited data on treatment outcomes of patients with malignant ovarian germ cell tumours (MOGCT). Here, we present our hospital audit of patients with MOGCT. MATERIAL AND METHODS: This is a retrospective data review of patients with MOGCT treated between May 2011 and December 2019. Patients were treated with staging laparotomy and adjuvant chemotherapy, wherever applicable. Surveillance was allowed for those at low risk for recurrence. Clinicopathologic features and treatment details were recorded, and survival analysis was performed. RESULTS: Sixty-five patients with a median age of 25 years (range: 11-52 years) were treated during the study period. The most common histology was immature teratoma in 35.3% of cases. International Federation of Gynecology and Obstetrics stage IC was the most common stage of presentation (47%). Surveillance was advised for 12.3% of cases. Systemic therapy was given in 51 (78%) patients. At a median follow-up of 46 months (range: 1-109 months), the median progression-free survival (PFS) was not reached. Five-year PFS was 79.3% (95% CI: 65.8-88). The most common toxicity was febrile neutropenia (22%) among those who received systemic therapy. CONCLUSION: Immature teratoma was the most common histology in our series. The majority presented in the early stage. MOGCT is a highly curable disease with surgery and systemic therapy.

6.
Pleura Peritoneum ; 6(3): 99-111, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34676283

ABSTRACT

OBJECTIVES: Enhanced recovery after surgery (ERAS) protocols have been questioned in patients undergoing cytoreductive surgery (CRS) with/without hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal malignancies. This survey was performed to study clinicians' practice about ERAS in patients undergoing CRS-HIPEC. METHODS: An online survey, comprising 76 questions on elements of prehabilitation (n=11), preoperative (n=8), intraoperative (n=16) and postoperative (n=32) management, was conducted. The respondents included surgeons, anesthesiologists, and critical care specialists. RESULTS: The response rate was 66% (136/206 clinicians contacted). Ninety-one percent of respondents reported implementing ERAS practices. There was encouraging adherence to implement the prehabilitation (76-95%), preoperative (50-94%), and intraoperative (55-90%) ERAS practices. Mechanical bowel preparation was being used by 84.5%. Intra-abdominal drains usage was 94.7%, intercostal drains by 77.9% respondents. Nasogastric drainage was used by 84% of practitioners. The average hospital stay was 10 days as reported by 50% of respondents. A working protocol and ERAS checklist have been designed, based on the results of our study, following recent ERAS-CRS-HIPEC guidelines. This protocol will be prospectively validated. CONCLUSIONS: Most respondents were implementing ERAS practices for patients undergoing CRS-HIPEC, though as an extrapolation of colorectal and gynecological guidelines. The adoption of postoperative practices was relatively low compared to other perioperative practices.

7.
Appl Opt ; 60(28): 8728-8736, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34613098

ABSTRACT

The accuracy of particle detection and size estimation is limited by the physical size of the digital sensor used to record the hologram in a digital in-line holographic imaging system. In this paper, we propose to utilize the autoregressive (AR) interpolation of the hologram to increase pixel density and, effectively, the quality of hologram reconstruction. Simulation studies are conducted to evaluate the influence of AR interpolation of a hologram on the accuracy of detection and size estimation of single and multiple particles of varying sizes. A comparative study on the performance of different interpolation techniques indicates the advantage of the proposed AR hologram interpolation approach. An experimental result is provided to validate the suitability of the proposed algorithm in practical applications.

8.
Appl Opt ; 60(4): 1031-1040, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33690417

ABSTRACT

A new autofocusing algorithm for digital holography is proposed based on the eigenvalues of the images reconstructed at different distances in the measurement volume. An image quality metric evaluated based on the distribution of its eigenvalues is compared in function of the reconstruction distance to identify the location of the focal plane. The proposed automatic focal plane detection algorithm is capable of working with amplitude objects, phase objects, and mixed type objects. A performance comparison of the proposed algorithm with some previously reported representative algorithms is provided. The simulation and experimental results demonstrate the practical applicability of the proposed algorithm.

9.
ACS Appl Mater Interfaces ; 13(13): 15610-15620, 2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33780228

ABSTRACT

Functional elastomers with incredible toughness and stretchability are indispensable for applications in soft robotics and wearable electronics. Furthermore, coupled with excellent electrical and thermal properties, these materials are at the forefront of recent efforts toward widespread use in cutting-edge electronics and devices. Herein, we introduce a highly deformable eutectic-GaIn liquid metal alloy-embedded natural rubber (NR) architecture employing, for the first time, industrially viable solid-state mixing and vulcanization. Standard methods of rubber processing and vulcanization allow us to fragment and disperse liquid metals into submicron-sized droplets in cross-linked NR without compromising the elastic properties of the base matrix. In addition to substantial boosts in mechanical (strain at failure of up to ∼650%) and elastic (negligible hysteresis loss) performances, the tearing energy of the composite was enhanced up to 6 times, and a fourfold reduction in the crack growth rate was achieved over a control vulcanizate. Moreover, we demonstrate improved thermal conductivity and dielectric properties for the resulting composites. Therefore, this work provides a facile and scalable pathway to develop liquid metal-embedded soft elastomeric composites that could be instrumental toward potential applications in soft-matter engineering.

10.
Heliyon ; 6(8): e04659, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32904204

ABSTRACT

The major controlling factors that determine the various mechanical properties of an elastomer system are type of chemical crosslinking and crosslink density of the polymer network. In this study, a catalytic amount of acrylonitrile butadiene copolymer (NBR) was used as a co-accelerator for the curing of polybutadiene (BR) elastomer. After the addition of this copolymer along with other conventional sulphur ingredients in polybutadiene compounds, a clear and distinct effect on the curing and other physical characteristics was noticed. The crosslinking density of BR was increased, as evidenced by rheometric properties, solid-state NMR and swelling studies. The vulcanization kinetics study revealed a substantial lowering of the activation energy of the sulphur crosslinking process when acrylonitrile butadiene copolymer was used in the formulation. The compounds were also prepared in the presence of carbon black and silica, and it was found that in the carbon black filled system the catalytic effect of the NBR was eminent. The effect was not only reflected in the mechanical performance but also the low-temperature crystallization behavior of BR systems was altered.

11.
J Obstet Gynaecol India ; 70(4): 289-294, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32764850

ABSTRACT

BACKGROUND: Women with response to primary treatment for advanced ovarian cancer are said to have progression if CA125 increases more than double the upper normal limit (70 IU/L) on follow-up. It was, however, noted that large section of women with CA125 > 35 IU/L had disease on imaging. OBJECTIVE: To compare values of CA125 rise at which radiological recurrence can be detected. METHODS: This is a retrospective observational study where women with advanced epithelial ovarian cancer who underwent interval debulking surgery and completed treatment at Tata Medical Center, Kolkata, India, from 2012 to 2016, and were followed up with Ca125. If CA125 doubled or exceeded 35 IU/L or increased to ≥ 70 IU/L, women were subjected to imaging. RESULTS: Among 142 women who underwent treatment, 64 women with response to primary treatment had recurrence. Recurrence was noted in two (3%) patients with doubling of Ca125 but ≤ 35 IU/, 18 (24%) patients with CA125 > 35 IU/L and 41 (64%) patients when CA125 was ≥ 70 IU/L. Three patients (5%) with normal CA125 had recurrence. Among the recurrence group, 45 women had R0 during surgery of which 27 (60%) had CA125 ≥ 70 IU/L and 14 (31%) had CA125 > 35 IU/L during recurrence. Sensitivity and specificity of value > 35 IU/L were 30.51% and 33.33%, respectively, with accuracy of 32.03%, while sensitivity and specificity at > 70 IU/L were 69.49% and 66.67%, respectively, with accuracy of 67.97%. CONCLUSION: CA125 value of ≥ 70 IU/L is a better predictor of recurrence; however, imaging done when value rises > 35 IU/L would be able to detect significant recurrences early thus allowing early treatment.

12.
ACS Appl Bio Mater ; 3(11): 7898-7907, 2020 Nov 16.
Article in English | MEDLINE | ID: mdl-35019530

ABSTRACT

A scalable method for the assembly of oriented bacterial cellulose (BC) films is presented based on using wrinkled thin silicone substrates of meter-square size as templates during biotechnological syntheses of BC. Control samples, including flat templated and template-free bacterial cellulose, along with the oriented BC, are morphologically characterized using scanning electron microscopy (SEM). Multiple functional properties including wettability, birefringence, mechanical strength, crystallinity, water retention, thermal stability, etc., are being characterized for the BC samples, where the wrinkling-induced in situ BC alignment not only significantly improved material mechanical properties (both strength and toughness) but also endowed unique material surface characteristics such as wettability, crystallinity, and thermal stability. Owing to the enhanced properties observed, potential applications of wrinkle templated BC in printing and cell culture are being demonstrated as a proof of concept, which renders their approach promising for various biomedical and packaging applications.

13.
ACS Omega ; 4(18): 17623-17633, 2019 Oct 29.
Article in English | MEDLINE | ID: mdl-31681869

ABSTRACT

Each year, hundreds of millions of tires are produced and ultimately disposed into nature. To address this serious environmental issue, devulcanization could be one of the sustainable solutions that still remains as one of the biggest challenges across the globe. In this work, sulfur-vulcanized natural rubber (NR) is mechanochemically devulcanized utilizing a silane-based tetrasulfide as a devulcanizing agent, and subsequently, silica (SiO2)-based rubber composites are prepared. This method not only breaks the sulfur-sulfur cross-links but also produces reactive poly(isoprene) chains to interact with silica. The silica natural rubber composites are prepared by replacing 30% fresh NR by devulcanized NR with varying contents of silica. The composites exhibit excellent mechanical properties, tear strength, abrasion resistance, and dynamic mechanical properties as compared with the fresh natural rubber silica composites. The tensile strength of devulcanized rubber-based silica composites is ∼20 MPa, and the maximum elongation strain is ∼921%. The devulcanized composites are studied in detail by chemical, mechanical, and morphological analyses. Thus, the value added by the devulcanized rubber could attract the attention of recycling community for its sustainable applications.

14.
Langmuir ; 35(22): 7155-7160, 2019 Jun 04.
Article in English | MEDLINE | ID: mdl-31050434

ABSTRACT

High-resolution inkjet printing of a hydrophobic polymer surface (polystyrene, PS) was accomplished using a patterned coating of cellulose nanocrystals (CNCs) that prevents the ink from bleeding. A periodically crack-free, wrinkled (wavelength of around 850 nm) stamp was prepared by surface oxidation of an uniaxially stretched poly(dimethylsiloxane) elastomeric substrate and was used as a template to transfer aligned patterns of cellulose nanocrystals (CNCs) onto PS surfaces by wet stamping. The morphology of the aligned CNC coatings on PS was then compared with randomly deposited CNCs on PS using atomic force microscopy. The wettability of the CNCs and polymer surfaces with water and ink was measured and analyzed in the context of inkjet printing. This biomaterial coating technique enables high-resolution printing of modern water-based inks onto hydrophobic surfaces for applications in renewable packaging and printing of biomolecules for high throughput diagnostics. Further, with suitable modifications, the technology is scalable to roll-to-roll manufacturing for industrial flexo printing.

16.
ACS Appl Mater Interfaces ; 10(18): 16148-16159, 2018 May 09.
Article in English | MEDLINE | ID: mdl-29676569

ABSTRACT

A mechanically adaptable elastomer composite is prepared with reversible soft-stiff properties that can be easily controlled. By the exploitation of different morphological structures of calcium sulfate, which acts as the active filler in a soft elastomer matrix, the magnitude of filler reinforcement can be reversibly altered, which will be reflected in changes of the final stiffness of the material. The higher stiffness, in other words, the higher modulus of the composites, is realized by the in situ development of fine nanostructured calcium sulfate dihydrate crystals, which are formed during exposure to water and, further, these highly reinforcing crystals can be transformed to a nonreinforcing hemihydrate mesocrystalline structure by simply heating the system in a controlled way. The Young's modulus of the developed material can be reversibly altered from ∼6 to ∼17 MPa, and the dynamic stiffness (storage modulus at room temperature and 10 Hz frequency) alters its value in the order of 1000%. As the transformation is related to the presence of water molecules in the crystallites, a hydrophilic elastomer matrix was selected, which is a blend of two hydrophilic polymers, namely, epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer and a terpolymer of ethylene oxide-propylene oxide-allyl glycidyl ether. For the first time, this method also provides a route to regulate the morphology and structure of calcium sulfate nanocrystals in a confined ambient of cross-linked polymer chains.

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