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1.
Heliyon ; 9(6): e16600, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484332

RESUMO

A rhodamine-derived receptor was synthesized and comprehensively characterized for structural confirmation. The receptor was able to distinguish the copper ions (Cu2+) from other competing cations. The yellow color of the receptor changed to pink upon adding Cu2+ ions, however, other competing cations ions were impotent towards any color variation. The UV-visible titration studies revealed the binding stoichiometry of a 1:1 ratio with a detection limit of 9.663 × 10-8 M. Additionally, a novel idea of the work resides in the use of diatom for the practical application, where the receptor has been tethered on nanoporous diatomaceous earth microparticles (P2D) to remove Cu2+ ions. The results confirmed that 50 mg receptor functionalized DE could adsorb 10 mL of 1 ppm Cu2+ ions from water. Furthermore, a proof-of-concept device that is inexpensive, simple to operate, and continuously removes Cu2+ ions from water has been developed. The efficiency of the device in Cu2+ ion removal could be realized through the naked eye by observing the color change of P2D particles, which has excellent potential for application in remote locations where water contamination is a significant issue.

2.
Anal Methods ; 15(26): 3259-3267, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37366572

RESUMO

A Schiff base receptor with an active -NH group was designed and synthesized for the selective and sensitive colorimetric detection of inorganic fluoride (F-) ions in an aqueous medium. The sensitivity of the receptor for F- ions was enhanced by the influence of two electron-withdrawing -NO2 groups at ortho and para positions which result in a vivid color change. The receptor underwent a remarkable color change from light yellow to violet, enabling naked-eye detection of F- ions without the need for spectroscopic equipment. To ensure the structural integrity of the synthesized receptors, prominent spectroscopic techniques such as 1H NMR, FTIR, and GCMS analysis were used for characterization. With a limit of detection (LoD) of 0.0996 ppm, a 1 : 2 stoichiometric binding ratio was observed for receptor and F- ions. The binding mechanism confirmed the deprotonation of the -NH group followed by the formation of -HF2, resulting in an intramolecular charge transfer (ICT) transition, which correlates with UV-vis and 1H NMR titration results. In addition, the proposed binding mechanism of F- ion interaction with the receptor was theoretically validated using DFT and TDDFT calculations. Furthermore, as a real-life implementation of the receptor, quantification of the F- ions present in a commercially available mouthwash was demonstrated. To assess the sensitivity performance, a paper-based dip sensor and a solid substrate sensor by functionalizing the receptor on diatomaceous earth were demonstrated. Finally, sensors were built into smartphones that could recognize the red, green, and blue percentages (RGB%) where each parameter defines the intensity of the color, which could also be used as a supplement to the colorimetric investigations.

3.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 2): 1973-1978, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36452640

RESUMO

Laryngopharyngeal cancers are one of the most commonly diagnosed head and neck malignancies frequently presenting primarily with change in voice. Radiotherapy being the main modality of treatment for early cancers continues to affect voice. Hence, acoustic analysis of the voice offers quantifiable values of several parameters delineating the obvious effect of the therapy. A total number of 60 patients, diagnosed with laryngopharyngeal cancers undergoing radiotherapy underwent acoustic voice assessment using Dr. speech software pre-treatment and at 1 and 3 months post radiotherapy. Data analysis was done using Mann-Whitney test and Wilcoxon signed rank test and a significant p value was obtained. The results of the study showed fundamental frequency (F0) and noise to harmonic ratio (NHR) to be the most affected in comparison to Jitter and Shimmer. The F0 and NHR values across baseline evaluation, first month and third month follow up showed a steady deterioration which was significant. The deterioration noted from the first to third month was not statistically significant. Across genders both F0 and NHR deterioration is more in males than in females. Radiotherapy causes definitive alterations in some acoustic measures of voice, which make the voice disharmonic and hoarse with contribution of harshness and breathiness. The effect is more pronounced on vocal parameters that are structure and projection based as evidenced by deterioration in values noted in F0 and NHR. Persistent deteriorated acoustic parameters for a longer duration of time are more likely which emphasizes the need for early voice rehabilitation.

4.
Biosensors (Basel) ; 12(4)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35448280

RESUMO

CTCs (circulating tumor cells) are well-known for their use in clinical trials for tumor diagnosis. Capturing and isolating these CTCs from whole blood samples has enormous benefits in cancer diagnosis and treatment. In general, various approaches are being used to separate malignant cells, including immunomagnets, macroscale filters, centrifuges, dielectrophoresis, and immunological approaches. These procedures, on the other hand, are time-consuming and necessitate multiple high-level operational protocols. In addition, considering their low efficiency and throughput, the processes of capturing and isolating CTCs face tremendous challenges. Meanwhile, recent advances in microfluidic devices promise unprecedented advantages for capturing and isolating CTCs with greater efficiency, sensitivity, selectivity and accuracy. In this regard, this review article focuses primarily on the various fabrication methodologies involved in microfluidic devices and techniques specifically used to capture and isolate CTCs using various physical and biological methods as well as their conceptual ideas, advantages and disadvantages.


Assuntos
Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes , Linhagem Celular Tumoral , Separação Celular , Humanos , Dispositivos Lab-On-A-Chip , Microfluídica/métodos
5.
Anal Chim Acta ; 1159: 338439, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33867030

RESUMO

A PDMS (Polydimethylsiloxane) microfluidic channel coupled with UV-vis fibre-optic spectrometer and new synthesized colorimetric probe was integrated into an optofluidic based Lab-on-a-chip device for highly sensitive and real-time quantitative measurements of fluoride ions (F¯). An 'S' shaped microchannel in a microfluidic device was designed to act as microreactor to facilitate the continuous reaction between synthetized colorimetric probe (sensor) and F¯ ions. Following this reaction, the UV-vis optical probe in the downstream detection zone of the microfluidic device was used to capture their spectrum and present as F¯ concentration in real-time conditions. An initial study of the developed colorimetric probe with multi-colour change with several binding and chromophore groups such as -OH, -NH and -NO2 groups confirmed its high sensitivity and selectivity for F¯ ions with a detection limit of 0.79 ppm. The performance of the developed optofluidic device was evaluated for the selective, sensitive detection of F¯ ions including real samples out-performing conventional methods. The technology has advantages such as low sample consumption, rapid analysis, high sensitivity and portability. Presented new Lab-on-a-chip device provides many competitive advantages for the real-time analysis of F¯ ions needed across broad sectors.


Assuntos
Fluoretos , Dispositivos Lab-On-A-Chip , Colorimetria , Microfluídica
6.
Anticancer Agents Med Chem ; 21(11): 1431-1440, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32664844

RESUMO

BACKGROUND: Coumarin and benzophenone possess a vast sphere of biological activities, whereas thiazoles display various pharmacological properties. Hence, present study focused on the incorporation of coumarin and thiazole core to the benzophenone skeleton to enhance the bioactivity, anticipating their interesting biological properties. OBJECTIVE: The objective of the current work is the synthesis and biological evaluation of a novel series of coumarin fused thiazole derivatives. METHODS: A novel series of coumarin conjugated thiazolyl acetamide hybrid derivatives were synthesized by a multistep reaction sequence and were characterized by the FT-IR, LCMS, and NMR spectral techniques. The newly synthesized compounds were screened for anti-cancer activity by in silico and in vitro methods. The cytotoxicity of the synthesized unique compounds was executed for two different cancer cell lines, MCF-7 (Breast cancer) and KB (Oral cancer), in comparison with standard paclitaxel by MTT assay. RESULTS: The compound 7f is a potent motif with an acceptable range of IC50 values, for anti-cancer activity, i.e., 63.54µg/ml and 55.67µg/ml, against the MCF-7 and KB cell lines, respectively. Molecule docking model revealed that this compound formed three conventional hydrogen bonds with the active sites of the amino acids, MET 769, ARG 817, and LYS 721. CONCLUSION: Compound 7f with two methyl groups on the phenoxy ring and one 4-position methoxy group on the benzoyl ring, showed a significant cytotoxic effect. An advantageous level of low toxicity against normal cell line (L292) by MTT assay was determined.


Assuntos
Acetamidas/farmacologia , Antineoplásicos/farmacologia , Cumarínicos/farmacologia , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Acetamidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cumarínicos/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
7.
ACS Nano ; 14(11): 15595-15604, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33119255

RESUMO

In this work, an approach to upcycling plastic waste (PW) products is presented. The method relies on flash Joule heating (FJH) to convert PW into flash graphene (FG). In addition to FG, the process results in the formation of carbon oligomers, hydrogen, and light hydrocarbons. In order to make high-quality graphene, a sequential alternating current (AC) and direct current (DC) flash is used. The FJH process requires no catalyst and works for PW mixtures, which makes the process suitable for handling landfill PW. The energy required to convert PW to FG is ∼23 kJ/g or ∼$125 in electricity per ton of PW, potentially making this process economically attractive for scale-up. The FG was characterized by Raman spectroscopy and had an I2D/IG peak ratio up to 6 with a low-intensity D band. Moreover, transmission electron microscopy and X-ray diffraction analysis show that the FG is turbostratic with an interlayer spacing of 3.45 Å. The large interlayer spacing will facilitate its dispersion in liquids and composites. Analysis of FG dispersions in 1% Pluronic aqueous solution shows that concentrations up to 1.2 mg/mL can be achieved. The carbon oligomers that distilled from the process were characterized by Fourier transform infrared spectroscopy and have chemical structures similar to the starting PW. Initial analysis of gas-phase products shows the formation of considerable amounts of hydrogen along with other light hydrocarbons. As graphene is naturally occurring and shows a low toxicity profile, this could be an environmentally beneficial method to upcycle PW.

8.
Childs Nerv Syst ; 36(5): 1049-1054, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31848723

RESUMO

PURPOSE: Discitis in the paediatric population poses diagnostic challenges due to non-specific presenting symptoms and difficulty with expressing pain in non-communicating children. Discitis remains a relatively rare condition in the paediatric population and previous reports are limited to small cohorts. In this article, we report our experience in management of discitis over a 10-year period and review the literature on this topic. METHODS: We retrospectively reviewed cases of paediatric discitis/spondylodiscitis over a 10-year period between 2008 and 2018 managed in our regional paediatric neurosurgery unit. Relevant demographic information, microbiological data, blood investigation profile, antibiotic treatment duration and clinical outcomes were interrogated from clinical notes and electronic databases and further analysed. RESULTS: Overall, 21 cases of paediatric discitis were identified from year 2008 to 2018 with a female to male ratio of 1.3:1. The mean age at presentation was 4.3 years (range 1 to 15 years). Overall, there were 19 cases of lumbosacral/lumbar, 1 thoracic and 1 cervical discitis. The mean duration of follow-up was 20 months (range 6 to 69 months). The most common presenting features were back pain and refusal to walk/sit or weight bear. Erythrocyte sedimentation rate (ESR) was found to be more sensitive than C-reactive protein (CRP) (sensitivity 78% versus 38%) in our cohort. Computer tomography (CT)-guided biopsy was performed in five cases and only one of these was positive (20%). All patients were treated with intravenous antibiotics with resolution of discitis. CONCLUSIONS: Presentation of discitis in children can be non-specific and requires high index of suspicion. CT-guided biopsy in our cohort revealed a low rate of positive cultures. Despite negative blood cultures and CT-guided biopsy results, empirical intravenous antibiotics were effective in treating discitis successfully. In our cohort, low yield of CT-guided biopsy does not support its use on each case and this may be reserved for cases resistant to antimicrobial therapy or concerns regarding other pathology mimicking infection. Better understanding and awareness of this condition and its pathophysiology can lead to timely imaging, diagnosis and treatment.


Assuntos
Discite , Adolescente , Antibacterianos/uso terapêutico , Biópsia , Criança , Pré-Escolar , Discite/diagnóstico , Discite/tratamento farmacológico , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 2): 1567-1571, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31750218

RESUMO

Worldwide, over 275 million people are estimated to have moderate to profound hearing loss in both ears. Children with hearing impairment often experience delayed development of speech and cognitive skills, which may result in slower learning and difficulty in progressing at school. Adequate hearing is one of the main factors for good psychosocial development, by which individuals may express their thoughts, feelings, and wishes, and acquire life experience and knowledge. Therefore, hearing impairment needs to be diagnosed early for prompt therapy. Primary objectives of this study was to know prevalence of hearing impairment amongst primary school children and secondary objective was to identify the common causes of hearing impairment amongst primary school children. The cross sectional study was conducted in the government and private schools of our rural field practice area in 2013-2014 for the duration of 4 months from November 2013 to February 2014. Prevalence of Hearing loss was 8.8%. Most common cause of Hearing loss was Impacted wax and Retracted Tympanic membrane. Otological conditions-Wax followed by otitis media with effusion and chronic suppurative otitis media were the common ear problems found in our study.

10.
Future Med Chem ; 10(1): 71-87, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29235357

RESUMO

AIM: Benzothiazole and pyrazoles are two important pharmacophores, the activity can be enhanced by conjugating them. Here, two novel series of the pyrazole-conjugated benzothiazole derivatives were synthesized. RESULTS: Synthesized compounds were characterized by Fourier-transform infrared, LC-MS, 1H NMR and 13C NMR spectroscopic techniques. Synthesized compounds exhibited moderate antimicrobial, antioxidant and excellent anti-TB activities. In in vitro anti-TB activity, 4d and 4e exhibited 1.6 µg/ml minimum inhibitory concentration value. In order to rationalize the anti-TB activity, molecular docking studies were carried out and they were correlated with the in vitro results. CONCLUSION: Compounds containing electron donating groups show the promising antimicrobial and antioxidant activities, compounds with CH3 and Cl substitution show excellent anti-TB activity. Synthesized molecules may become potential candidates for the clinical trials.


Assuntos
Antioxidantes/farmacologia , Antituberculosos/farmacologia , Benzotiazóis/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazóis/farmacologia , Tuberculose/tratamento farmacológico , Antioxidantes/síntese química , Antioxidantes/química , Antituberculosos/síntese química , Antituberculosos/química , Benzotiazóis/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazóis/química , Relação Estrutura-Atividade
11.
Chemistry ; 22(18): 6148-78, 2016 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-26890404

RESUMO

Computers have become smarter, smaller, and more efficient due to the downscaling of silicon-based components. Top-down miniaturisation of silicon-based computer components is fast reaching its limitations because of physical constraints and economical non-feasibility. Therefore, the possibility of a bottom-up approach that uses molecules to build nano-sized devices has been initiated. As a result, molecular logic gates based on chemical inputs and measurable optical outputs have captured significant attention very recently. In addition, it would be interesting if such molecular logic gates could be developed by making use of ion sensors, which can give significantly sensitive output information. This review provides a brief introduction to anion receptors, molecular logic gates, a comprehensive review on describing recent advances and progress on development of ion receptors for molecular logic gates, and a brief idea about the application of molecular logic gates.

12.
Asian Pac J Cancer Prev ; 15(10): 4147-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24935361

RESUMO

Standard therapy for advanced head and neck cancer consists of a combination of surgery and radiation. However, survival of this patient population has not improved during the past 20 years. Many different multimodality treatment schedules have been proposed, and chemotherapy is often used with the intent of organ preservation. The present study was intended to establish the efficacy of concomitant chemoradiation with a single agent carboplatin in advanced head and neck cancers.The objectives were to investigate the feasibility of concomitant administration of carboplatin, monitor acute toxicity during radiotherapy, and determine subacute side effects, such as wound healing following surgery after chemoradiotherapy. A prospective study was conducted wherein a total of 40 patients with stage III and IV squamous cell carcinomas of oral cavity, oropharynx, hypopharynx and larynx were enrolled. All patients were treated with external beam radiotherapy and weekly carboplatin area under curve (AUC of 5). Radiotherapy was given in single daily fractions of 1.8-2 grays (Gy) to a total dose of 66-72 Gy. Salvage surgery was performed for any residual or recurrent locoregional disease. Neck dissection was recommended for all patients with neck disease showing less than a complete response after chemoradiation. A total of 40 patients were enrolled of whom 32 were males and 8 were females. Highest incidence of cancer was seen in the 5th-6th decades of life with a median age of 47.7 years. Oropharyngeal tumours constituted a maximum of 21 patients followed by hypopharynx in 10, larynx in 7 and oral cavity in 2. 80% of the patients had a neck node on presentation of which 40% had N2-N3 nodal status. TNM staging revealed that 58% of patients were in stage III and 43% in stage IV. Evaluation of acute toxicity revealed that 50% had grade II mucositis, 25% grade III mucositis, 2.5% grade IV mucositis. 50% of patients had grade I skin reactions, 65% of patients had grade I thrombocytopenia, and 24% of patients had grade I anaemia. After completion of treatment 65% of patients had complete response at the primary and regional sites, and 35% of patients had a partial response of whom 23% underwent neck dissection and 5% of them underwent salvage surgery at the primary site. At the end of one year there were six deaths and four recurrences and 70% were free of disease. Concurrent chemoradiation with carboplatin provided good locoregional control for locally advanced head and neck cancers. This regimen, although toxic, is tolerable with appropriate supportive intervention. Primary site conservation is possible in many patients. Chemoradiotherapy appears to have an emerging role in the primary management of head and neck cancers.


Assuntos
Carboplatina/uso terapêutico , Carcinoma de Células Escamosas , Quimiorradioterapia/métodos , Terapia Combinada/métodos , Neoplasias de Cabeça e Pescoço , Adulto , Idoso , Anemia/patologia , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carboplatina/efeitos adversos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Intervalo Livre de Doença , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Hipofaríngeas/radioterapia , Neoplasias Hipofaríngeas/cirurgia , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/radioterapia , Neoplasias Bucais/cirurgia , Mucosite/patologia , Pescoço/patologia , Pescoço/cirurgia , Recidiva Local de Neoplasia/patologia , Neoplasias Orofaríngeas/tratamento farmacológico , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/cirurgia , Estudos Prospectivos , Dosagem Radioterapêutica , Terapia de Salvação , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida , Trombocitopenia/patologia , Cicatrização
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