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1.
Environ Sci Pollut Res Int ; 30(30): 74628-74670, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37231136

RESUMO

Radioactive iodine is a hazardous fission product and a major concern for public health. Special attention is paid to iodine out of 80 fission products because of its short half-life of 8.02 days, high activity, and potential health hazards like its irreversible accumulation in thyroid gland and ability to cause thyroid cancer locally. Radioactive iodine can get released in the form of aerosols (cesium iodide), elemental iodine, and organic iodide after a nuclear accident and can cause off-site and on-site contamination. Filtered containment venting system (FCVS) is a safety system whose main objective is mitigation of severe accidents via controlled venting and removal of different forms of iodine to ensure safety of people and environment. After nuclear accidents like Fukushima, extensive research has been done on the removal of iodine by using dry scrubbers. This review paper presents research status of iodine removal by dry adsorbents especially after 10 years of Fukushima to assess the progress, research gap, and challenges that require more attention. A good adsorbent should be cost-effective; it should have high selective adsorption towards iodine, high thermal and chemical stability, and good loading capacity; and its adsorption should remain unaffected by aging and the presence of inhibitors like CO, NO2, CH3Cl, H2O, and Cl2 and radiation. Research on different dry adsorbents was discussed, and their capability as a potential filter for FCVS was reviewed on the basis of all the above-mentioned features. Metal fiber filters have been widely used for removal of aerosols especially micro- and nanoscale aerosols. For designing a metal fiber filter, optimal size or combination of sizes of fibers, number of layers, and loading capacity of filter should be decided according to feasibility and requirement. Balance between flow resistance and removal efficiency is also very important. Sand bed filters were successful in retention of aerosols, but they showed low trapping of iodine and no trapping of methyl iodide at all. For iodine and methyl iodide removal, many adsorbents like activated carbon, zeolites, metal organic frameworks (MOFs), porous organic frameworks (POPs), silica, aerogels, titanosilicates, etc. have been used. Impregnated activated carbon showed good results but low auto-ignition temperature and decline in adsorption due to aging and inhibitors like NOx made them less suitable. Silver zeolites have been very successful in methyl iodide and iodine removal, but they are expensive and affected by presence of CO. Titanosilicates, macroreticular resins, and chalcogels were also studied and they showed good adsorption capacities, but their thermal stability was low. Other adsorbents like silica, MOFs, aerogels, and POPs also showed promising results for iodine adsorption and good thermal stability, but very limited or no research is available on their performance in severe accident conditions. This review will be very helpful for researchers to understand the merits and demerits of different types of dry adsorbents, the important operating parameters that need optimization for designing an efficient scrubber, margin of research, and foreseeable challenges in removal of different forms of iodine.


Assuntos
Acidente Nuclear de Fukushima , Iodo , Neoplasias da Glândula Tireoide , Zeolitas , Humanos , Radioisótopos do Iodo , Carvão Vegetal , Adsorção
2.
Natl J Maxillofac Surg ; 10(2): 134-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798246

RESUMO

INTRODUCTION: Health-related quality of life (HRQoL) is a more specific area of QoL that deals with the evaluation and assessment of the impact of the disease and its treatment-related morbidities on a patient's physical, psychological, and social aspects. The aim of the present study was to assess the HRQoL of patients with head-and-neck cancer (HNCs) during and at 3 months after completion of radiotherapy (RT) by intensity-modulated RT. MATERIALS AND METHODS: This study was a prospective, longitudinal, observational, and self-completed questionnaire-based study that included 120 patients with HNC who underwent intensity-modulated RT. The questionnaire had adequate internal consistency. The questionnaires were given to each patient at the beginning of treatment (pretreatment), weekly visits during the course of RT (at the end of 1st, 2nd, 3rd, 4th, 5th, and 6th week), on the day of completion of RT, and then finally at 3 months after completion of RT. Thus, a total of successive nine time points were assessed. RESULTS AND CONCLUSIONS: One hundred and eleven patients completed the questionnaires at all nine time points. HRQoL usually decreases during treatment and then increases to pretreatment levels by 3 months after treatment. The Quality of Life Questionnaire, Core Module and Quality of Life Questionnaire, Head and Neck Module were found to be both valid and reliable. There was a significant QoL reduction for the patients throughout treatment in relation to functions and symptoms in the treatment of HNC. However, all the functions and most of the symptoms returned to baseline at the 3-month follow-up.

3.
Autophagy ; 15(10): 1810-1828, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30894052

RESUMO

Imbalance in production and clearance of amyloid beta (Aß) is the primary reason for its deposition in Alzheimer disease. Macroautophagy/autophagy is one of the important mechanisms for clearance of both intracellular and extracellular Aß. Here, through screening, we identified alborixin, an ionophore, as a potent inducer of autophagy. We found that autophagy induced by alborixin substantially cleared Aß in microglia and primary neuronal cells. Induction of autophagy was accompanied by up regulation of autophagy proteins BECN1/Beclin 1, ATG5, ATG7 and increased lysosomal activities. Autophagy induced by alborixin was associated with inhibition of the phosphoinositide 3-kinase (PI3K)-AKT pathway. A knock down of PTEN and consistent, constitutive activation of AKT inhibited alborixin-induced autophagy and consequent clearance of Aß. Furthermore, clearance of Aß by alborixin led to significant reduction of Aß-mediated cytotoxicity in primary neurons and differentiated N2a cells. Thus, our findings put forward alborixin as a potential anti-Alzheimer therapeutic lead. Abbreviations: Aß: amyloid beta; ALB: alborixin; ATG: autophagy-related; BECN1: beclin 1; DAPI: 4, 6-diamidino-2-phenylindole; DCFH-DA: 2,7-dichlorodihydrofluorescein diacetate; fAß: fibrillary form of amyloid beta; GFAP: glial fibrillary acidic protein; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MAP2: microtubule-associated protein 2; MTOR: mechanistic target of rapamycin kinase; PTEN: phosphatase and tensin homolog; ROS: reactive oxygen species; SQSTM1: sequestosome 1; TMRE: tetramethylrhodamine, ethyl ester.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Autofagia/efeitos dos fármacos , PTEN Fosfo-Hidrolase/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Autofagia/fisiologia , Células Cultivadas , Embrião de Mamíferos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , PTEN Fosfo-Hidrolase/genética , Proteólise/efeitos dos fármacos , Piranos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
4.
Head Neck ; 41(6): 1632-1637, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30582238

RESUMO

BACKGROUND: Labeling locoregional failures in head and neck cancer (HNC) as "local" and "regional" becomes incomplete when treating with intensity modulated radiotherapy (IMRT). Target delineation and delivery errors, dose in-homogeneity complicate the assessment of failures. A combination of focal point and dosimetric method might attempt at simplifying failure analysis. METHODS: One hundred eleven patients with locally advanced HNC treated with chemoradiation using IMRT were enrolled. Patients with documented failure had their recurrence volume assessed using focal point and dosimetric method. RESULTS: With a median follow-up of 20 (range 0-39) months and median locoregional control (LRC) of 30 (range 24.8-34.5) months, the patients had a 3-year overall survival and LRC of 70.6% and 48.9%, respectively. Of 39 failures, there were 69.2%, 7.6%, 5.1%, 12.8%, and 5.1% type A, B, C, D, and E, respectively using the focal point and dosimetric method. CONCLUSION: With the current classification, majority of the recurrences were high dose failures suggesting inherent radioresistance. While minority of failures were potentially preventable and needed modifying existing IMRT workflow.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Radiometria/métodos , Radioterapia de Intensidade Modulada , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/mortalidade , Quimiorradioterapia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Prospectivos , Falha de Tratamento , Adulto Jovem
5.
Lung India ; 35(1): 54-57, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29319036

RESUMO

This is a case report of a 60-year-old diabetic, hypertensive male with a good performance status and a history of bilateral interstitial lung disease with a left upper lobe lung mass diagnosed to be a Stage IIB mixed small-cell/squamous cell carcinoma which was refractory to carboplatin- and etoposide-based chemotherapy. The patient was then taken up for adaptive intensity-modulated radiotherapy with tighter margin under image guidance with a mid-treatment replanning done at 25#. Acute toxicities were assessed weekly and showed no Grade 3 or more reactions. Pulmonary function test showed no detrimental changes during or after radiation. Response assessment at 12 and 20 weeks showed a partial response with decrease in metabolic activity on serial scans.

6.
Sci Rep ; 6: 33146, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27680387

RESUMO

In this study, we investigated the role of autophagy induced by boswellic acid analog BA145 on cell cycle progression in pancreatic cancer cells. BA145 induced robust autophagy in pancreatic cancer cell line PANC-1 and exhibited cell proliferation inhibition by inducing cells to undergo G2/M arrest. Inhibition of G2/M progression was associated with decreased expression of cyclin A, cyclin B, cyclin E, cdc2, cdc25c and CDK-1. Pre-treatment of cells with autophagy inhibitors or silencing the expression of key autophagy genes abrogated BA145 induced G2/M arrest and downregulation of cell cycle regulatory proteins. It was further observed that BA145 induced autophagy by targeting mTOR kinase (IC50 1 µM), leading to reduced expression of p-mTOR, p-p70S6K (T389), p-4EBP (T37/46) and p-S6 (S240/244). Notably, inhibition of mTOR signalling by BA145 was followed by attendant activation of AKT and its membrane translocation. Inhibition of Akt through pharmacological inhibitors or siRNAs enhanced BA145 mediated autophagy, G2/M arrest and reduced expression of G2/M regulators. Further studies revealed that BA145 arbitrated inhibition of mTOR led to the activation of Akt through IGFR/PI3k/Akt feedback loop. Intervention in IGFR/PI3k/Akt loop further depreciated Akt phosphorylation and its membrane translocation that culminates in augmented autophagy with concomitant G2/M arrest and cell death.

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