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1.
Dermatol Ther ; 33(6): e14242, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32860351

RESUMO

This is the first study to evaluate the topical application of Lobelia alsinoides Lam (LT) ethanolic extract on burns in rats. A deep third-degree burn wound was inflicted in adult male Wistar rats and the burns were dressed daily with a topical ointment formulation (Patent filed) comprising of Lobelia alsinoides Lam (5% and 10% w/w). The wound had noteworthy contraction and quicker eschar removal in 10% w/w LT-treated groups followed by 5% w/w treated groups on comparing with the commonly prescribed ointment (SilverexTM containing 1% w/w Silver sulfadiazine). Histopathological analysis showed that ointment containing 10% w/w LT ethanolic extract significantly increased fibroblast growth, which plays a major role in anatomic integrity, collagen synthesis, and accelerated the rate of the healing process. This study shows that the ethanolic extract of Lobelia alsinoides Lam, a previously pharmacologically unreported traditional medicinal plant, possesses wound contraction and eschar removal properties on burn wounds.


Assuntos
Queimaduras , Lobelia , Animais , Queimaduras/tratamento farmacológico , Masculino , Extratos Vegetais , Ratos , Ratos Wistar , Cicatrização
2.
Appl Radiat Isot ; 173: 109721, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33895528

RESUMO

In-vivo lung monitoring is an important technique for the assessment of internal dose of radiation workers handling actinides. At BARC, counting efficiencies (CEs) of detection systems used for estimation of natural uranium in the lungs are evaluated using realistic thorax physical phantoms or computational voxel phantoms. The quantification of 238U and 235U in lungs is done using CEs determined at 63.3 keV and 185.7 keV photon energies respectively. These CEs can also be used for assessment of enriched uranium in the lungs of the workers. In this study, spectra are generated for HPGe array detectors using Monte Carlo simulations of various enriched uranium compositions distributed in the lungs of thorax voxel phantom. A methodology is developed to predict the 235U enrichment from lung spectrum analysis using the ratio of net counts in 185.7 keV and 63.3 keV energy regions. It is possible to estimate enrichments in the range of 2%-30% using the developed method with less than ±9% error. Finally, effect of 235U enrichment on dose assessment using lung monitoring method is studied.


Assuntos
Pulmão/efeitos da radiação , Imagens de Fantasmas , Monitoramento de Radiação/métodos , Urânio/metabolismo , Humanos , Pulmão/metabolismo , Método de Monte Carlo , Doses de Radiação , Urânio/administração & dosagem
3.
Food Funct ; 12(11): 5038-5050, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33960359

RESUMO

Rheumatoid Arthritis (RA) is an autoimmune disease that commences as inflammation and progressively destroys the articular joint. In this study, we assess the anti-rheumatic potential of the monoterpenoid class of thymol conjugated with Carbon Dots (CDs). Waste biomass in the form of dried rose petals was chosen as a precursor for the synthesis of CDs via a one-step hydrothermal bottom-up methodology. The prepared CDs exhibited absorption in the near-visible region, and unique excitation-dependent emission behaviour was confirmed from UV-Visible and fluorescence measurements. The surface morphology of CDs was confirmed by SEM and HR-TEM analysis to be quasi-spherical particles with an average size of ∼5-6 nm. The presence of various functional moieties (hydroxyl, carbonyl, and amino) was confirmed via FT-IR measurement. The graphitization of CDs was confirmed by the D and G bands for sp2 and sp3 hybridization, respectively, through Raman analysis. Esterification methodology was adopted to prepare the CDs-thymol conjugate and confirmed via FT-IR analysis. CDs play the role of a nanocarrier for thymol, an anti-arthritic agent. The bioactive compound of thymol showed potent anti-arthritic activity against RA targets through in silico docking studies. Further, the in vivo studies revealed that CDs-thymol conjugates (10 mg per kg body weight) showed a significant reduction in rat paw volume along with reduced levels of RF and CRP (2.23 ± 0.42 IU ml-1 and 16.96 ± 0.22 mg ml-1) when compared to the disease control rats. X-ray radiography and ultrasonic imaging revealed less bone destruction, joint derangement, and swelling in arthritis-induced Wistar rats. They could also potentially improve the Hb (14.14 ± 0.19), RBC (6.01 ± 0.11), PCV (6.01 ± 0.11) levels and elevate the status of antioxidant enzymes (GPx, SOD, MDA), and the activity was comparable to the standard drug, ibuprofen (10 mg kg-1), suggesting that the CDs-thymol conjugate at 10 mg kg-1 could act as a strong anti-arthritic agent. This work is evidence for the utilization of waste biomass as a value-added product such as a nanocarrier for biomedical applications.


Assuntos
Antirreumáticos/química , Antirreumáticos/farmacologia , Carbono/química , Pontos Quânticos , Timol/química , Animais , Antioxidantes , Artrite Reumatoide/tratamento farmacológico , Feminino , Interleucinas/química , Metaloproteinase 1 da Matriz/química , Metaloproteinase 3 da Matriz/química , Simulação de Acoplamento Molecular , Ratos , Ratos Wistar , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fator de Crescimento Transformador beta/química
4.
Appl Radiat Isot ; 143: 67-71, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30390502

RESUMO

Counting statistics is an important parameter that can introduce uncertainties in the lung activity measurements of actinides in radiation workers. Evaluation of uncertainties due to counting statistics is practically difficult as it requires monitoring various radiation workers having different levels of lung actinide content, multiple times, each for 50 min of monitoring period. However, different activities in lungs can be simulated by combining uncontaminated male data with LLNL phantom data acquired with 241Am and natural uranium lung sets at various short periods. Therefore, multiple measurements were carried out on realistic thorax LLNL phantom with 241Am and natural uranium lung sets for 15-600 s. The mean counts with the phantom at various time intervals, corresponds to different actinide activities in lungs, assuming they are obtained for 50 min of monitoring interval. Using propagation of error, standard deviations were evaluated for combined phantom and uncontaminated adult male data. The combined standard deviations and mean phantom counts are used to evaluate scattering factors (SFs) for uncertainties due to counting statistics for Phoswich and HPGe array detectors. The SFs due to counting statistics are found to be the function of lung activities of radionuclides as well as energies and yields of the photons emitted by radionuclides. SFs are found to increase with decrease in lung activity. For similar yields photons, SFs are found to be lower for higher energy photons compared to lower energy photons. For photons of similar energies, the SFs are lower when yield is higher compared to lower yield photons.


Assuntos
Elementos da Série Actinoide/análise , Elementos da Série Actinoide/toxicidade , Pulmão/química , Pulmão/efeitos da radiação , Monitoramento de Radiação/métodos , Adulto , Amerício/análise , Humanos , Masculino , Exposição Ocupacional/análise , Imagens de Fantasmas , Exposição à Radiação/análise , Monitoramento de Radiação/estatística & dados numéricos , Incerteza , Urânio/análise
5.
3 Biotech ; 8(8): 343, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30073128

RESUMO

This study investigated the wound healing properties of the aqueous extract of Morinda tinctoria Roxb leaves in rats. The study also provides information on the purification, qualitative, and quantitative analysis of phytochemical components present in M. tinctoria Roxb. Wound contraction and period of epithelialization was determined and topical application of M. tinctoria Roxb aqueous leaf extract showed better healing than orally treated and control groups. The results suggest that the efficacy of M. tinctoria Roxb aqueous leaf extract as a wound healing agent and can also be used as a therapeutic agent for internal as well as external wounds.

6.
Radiat Prot Dosimetry ; 173(4): 308-317, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26922786

RESUMO

In case of internal contamination of actinides by ingestion pathway, activity will be transferred to various regions of the alimentary tract over a period of time. In this article, counting efficiencies (CEs) of Phoswich and an array of HPGe detectors are estimated for source in alimentary tract of voxel phantom. The phantom as well as Phoswich, and an array of three HPGe detectors are incorporated in Monte Carlo code 'FLUKA'. Human alimentary tract model is solved using default parameters to identify different compartments where activity will accumulate after an ingestion intake of 1 Bq as a function of time. Accordingly, CEs are evaluated on 0.5-5 d post ingestion intake for the source distributed in the contents of alimentary tract for photon energies in 18-238 keV range representing sources of actinides. The assessment of ingested activity of actinides from abdomen measurements is discussed. Higher CEs are observed with Phoswich detector compared with HPGe array due to its large size and high effective Z. Also, the CEs observed on Days 1-5 using both the detectors are found to decrease by 16-75 % with respect to the CE on half day. Thus, there is need to use CEs according to the observed activity distribution post ingestion intake. The contribution in the abdomen measurements due to source in the lungs and vice versa is also studied for intake by both inhalation and ingestion pathways. The contribution of source in the liver is found to be ∼30-50 % in chest and 75 % in abdomen measurements.


Assuntos
Elementos da Série Actinoide , Método de Monte Carlo , Imagens de Fantasmas , Simulação por Computador , Humanos , Fótons , Tórax
7.
Appl Radiat Isot ; 127: 109-115, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28570915

RESUMO

Various parameters can introduce uncertainties in the lung activity measurements of actinides. In this study, uncertainties due to non-uniform distribution of activity in the lungs are evaluated. To study the effect of non-uniform distribution, lungs of ICRP male thorax voxel and resized phantoms are divided into upper and lower parts of both right and left lungs as well as into anterior and posterior lung regions. Simulation of uniform and non-uniform distribution of activity in lungs is carried out using thorax voxel phantoms in FLUKA for Phoswich and an array of three HPGe detectors for 18-238keV photons. Source sampling for non-uniform distribution of activity is carried out by selecting the source points by varying the weightage to 0.4, 0.5, 0.6 and 1 in different parts of lungs. Uncertainties in lung activity estimation at different energies are quantified in the form of scattering factors (SFs) which are geometric standard deviations. The SFs due to non-uniform distribution of activity of the order of 0.4-0.6 in different parts of the lungs are found to be ~ 1.25 for Phoswich and HPGe array detectors above 18keV.


Assuntos
Elementos da Série Actinoide/análise , Pulmão/efeitos da radiação , Exposição à Radiação/análise , Elementos da Série Actinoide/efeitos adversos , Elementos da Série Actinoide/farmacocinética , Simulação por Computador , Humanos , Pulmão/metabolismo , Masculino , Método de Monte Carlo , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Imagens de Fantasmas , Exposição à Radiação/efeitos adversos , Radiometria/métodos , Radiometria/estatística & dados numéricos , Distribuição Tecidual , Incerteza
8.
Radiat Prot Dosimetry ; 167(4): 461-71, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25468992

RESUMO

Assessment of intake due to long-lived actinides by inhalation pathway is carried out by lung monitoring of the radiation workers inside totally shielded steel room using sensitive detection systems such as Phoswich and an array of HPGe detectors. In this paper, uncertainties in the lung activity estimation due to positional errors, chest wall thickness (CWT) and detector background variation are evaluated. First, calibration factors (CFs) of Phoswich and an array of three HPGe detectors are estimated by incorporating ICRP male thorax voxel phantom and detectors in Monte Carlo code 'FLUKA'. CFs are estimated for the uniform source distribution in lungs of the phantom for various photon energies. The variation in the CFs for positional errors of ±0.5, 1 and 1.5 cm in horizontal and vertical direction along the chest are studied. The positional errors are also evaluated by resizing the voxel phantom. Combined uncertainties are estimated at different energies using the uncertainties due to CWT, detector positioning, detector background variation of an uncontaminated adult person and counting statistics in the form of scattering factors (SFs). SFs are found to decrease with increase in energy. With HPGe array, highest SF of 1.84 is found at 18 keV. It reduces to 1.36 at 238 keV.


Assuntos
Elementos da Série Actinoide/farmacocinética , Pulmão/efeitos da radiação , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Monitoramento de Radiação/estatística & dados numéricos , Adulto , Simulação por Computador , Humanos , Masculino , Modelos Biológicos , Tórax/efeitos da radiação , Incerteza
9.
Eplasty ; 15: e36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26301001

RESUMO

HYPOTHESIS: Using Lister's tubercle and the ulnar styloid as landmarks, accurate localization of the distal radioulnar joint can be achieved without the need for an image-guided approach. METHODS: Cadaveric dissection of 16 upper extremities was performed to measure the relationships between the ulnar styloid, Lister's tubercle, and the distal radioulnar joint. In each specimen, the location of the distal radioulnar joint (point A) in relation to Lister's tubercle and the ulnar styloid was determined as follows: (1) the perpendicular distance between the distal radioulnar joint and ulnar styloid-Lister's tubercle was measured; (2) with A' marking the intersection of this distance and the ulnar styloid-Lister's tubercle line, the location of the distal radioulnar joint along the ulnar styloid-Lister's tubercle axis was determined by comparing ulnar styloid-A' and A'-Lister's tubercle with ulnar styloid-Lister's tubercle. RESULTS: The mean distance between ulnar styloid-Lister's tubercle was 4.3 ± 0.4 cm. The mean perpendicular distance between the distal radioulnar joint and the ulnar styloid-Lister's tubercle line was 0.2 ± 0.1 cm proximal to the ulnar styloid-Lister's tubercle line. The ratio of ulnar styloid-A' and A'-Lister's tubercle to ulnar styloid-Lister's tubercle was 0.5 ± 0.03 and 0.5 ± 0.03, respectively. CONCLUSIONS: Simple relationships between the ulnar styloid and Lister's tubercle serve as reliable landmarks for locating the distal radioulnar joint. The distal radioulnar joint is centered about the midpoint of the ulnar styloid-Lister's tubercle axis and slightly proximal to it. This may improve the accuracy and efficacy of corticosteroid injections in the treatment of distal radioulnar joint arthritis without the need for image guidance.

10.
Appl Radiat Isot ; 104: 49-54, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26141295

RESUMO

The estimation of Pu/(241)Am ratio in the biological samples is an important input for the assessment of internal dose received by the workers. The radiochemical separation of Pu isotopes and (241)Am in a sample followed by alpha spectrometry is a widely used technique for the determination of Pu/(241)Am ratio. However, this method is time consuming and many times quick estimation is required. In this work, Pu/(241)Am ratio in the biological sample was estimated with HPGe detector based measurements using gamma/X-rays emitted by these radionuclides. These results were compared with those obtained from alpha spectroscopy of sample after radiochemical analysis and found to be in good agreement.


Assuntos
Amerício/análise , Raios gama , Germânio/efeitos da radiação , Exposição Ocupacional/análise , Plutônio/análise , Espectrometria gama/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
IEEE Trans Image Process ; 7(1): 119-24, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-18267386

RESUMO

This paper presents a novel technique for image restoration based on nonlinear interpolative vector quantization (NLIVQ). The algorithm performs nonlinear restoration of diffraction-limited images concurrently with quantization. It is trained on image pairs consisting of an original image and its diffraction-limited counterpart. The discrete cosine transform is used in the codebook design process to control complexity. Simulation results are presented that demonstrate improvements in visual quality and peak signal-to-noise ratio of the restored images.

12.
IEEE Trans Neural Netw ; 4(5): 873-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-18276516

RESUMO

A new nonrecurrent associative memory model is proposed. This model is composed of a nonlinear transformation in the spectral domain followed by the association. The Moore-Penrose pseudoinverse is employed to obtain the least squares optimal solution. Computer simulations are done to evaluate the performance of the model. The simulations use one-dimensional speech signals and two-dimensional head/shoulder images. Comparison of the proposed model with the classical optimal linear associative memory and an optimal nonlinear associative memory is presented.

13.
Radiat Prot Dosimetry ; 162(4): 469-77, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24435911

RESUMO

In case of internal contamination due to long-lived actinides by inhalation or injection pathway, a major portion of activity will be deposited in the skeleton and liver over a period of time. In this study, calibration factors (CFs) of Phoswich and an array of HPGe detectors are estimated using skull and knee voxel phantoms. These phantoms are generated from International Commission of Radiation Protection reference male voxel phantom. The phantoms as well as 20 cm diameter phoswich, having 1.2 cm thick NaI (Tl) primary and 5cm thick CsI (Tl) secondary detector and an array of three HPGe detectors (each of diameter of 7 cm and thickness of 2.5 cm) are incorporated in Monte Carlo code 'FLUKA'. Biokinetic models of Pu, Am, U and Th are solved using default parameters to identify different parts of the skeleton where activity will accumulate after an inhalation intake of 1 Bq. Accordingly, CFs are evaluated for the uniform source distribution in trabecular bone and bone marrow (TBBM), cortical bone (CB) as well as in both TBBM and CB regions for photon energies of 18, 60, 63, 74, 93, 185 and 238 keV describing sources of (239)Pu, (241)Am, (238)U, (235)U and (232)Th. The CFs are also evaluated for non-uniform distribution of activity in TBBM and CB regions. The variation in the CFs for source distributed in different regions of the bones is studied. The assessment of skeletal activity of actinides from skull and knee activity measurements is discussed along with the errors.


Assuntos
Fótons/efeitos adversos , Monitoramento de Radiação/estatística & dados numéricos , Elementos da Série Actinoide/efeitos adversos , Elementos da Série Actinoide/farmacocinética , Carga Corporal (Radioterapia) , Simulação por Computador , Humanos , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/efeitos da radiação , Limite de Detecção , Masculino , Modelos Biológicos , Método de Monte Carlo , Exposição Ocupacional , Imagens de Fantasmas , Radiometria , Crânio/anatomia & histologia , Crânio/efeitos da radiação
14.
Radiat Prot Dosimetry ; 155(3): 292-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23390143

RESUMO

This study presents the simulation results for 10.16 cm diameter and 7.62 cm thickness NaI(Tl) detector response, which is housed in a partially shielded scanning bed whole-body monitor (WBM), due to activity distributed in the axial cavities provided in the Indian reference BOMAB phantom. Experimental detection efficiency (DE) for axial cavity activity distribution (ACAD) in this phantom for photon emissions of (133)Ba, (137)Cs and (60)Co is used to validate DEs estimated using Monte Carlo code FLUKA. Simulations are also carried out to estimate DEs due to uniform activity distribution (UAD) as in the standard BOMAB phantom. The results show that the DE is ∼3.8 % higher for UAD when compared with ACAD in the case of (40)K (1460 keV) and this relative difference increases to ∼7.0 % for (133)Ba (∼356 keV) photons. The corresponding correction factors for calibration with Indian phantom are provided. DEs are also simulated for activity distributed as a planar disc at the centre of the axial cavity in each part of the BOMAB phantom (PDAD) and the deviations of these DEs are within 1 % of the ACAD results. Thus, PDAD can also be used for ACAD in scanning geometry. An analytical solution for transmitted mono-energetic photons from a two-dimensional slab is provided for qualitative explanation of difference in DEs due to variation in activity distributions in the phantom. The effect on DEs due to different phantom part dimensions is also studied and lower DEs are observed for larger parts.


Assuntos
Iodetos/química , Método de Monte Carlo , Imagens de Fantasmas , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Sódio/química , Tálio/química , Imagem Corporal Total/instrumentação , Contagem Corporal Total/instrumentação , Calibragem , Simulação por Computador , Humanos , Fótons
15.
Radiat Prot Dosimetry ; 153(1): 32-46, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22645381

RESUMO

The ICRP/ICRU adult male reference voxel phantom incorporated in Monte Carlo code FLUKA is used for estimating specific absorbed fractions (SAFs) for photons due to the presence of internal radioactive contamination in the human respiratory tract (RT). The compartments of the RT, i.e. extrathoracic (ET1 and ET2) and thoracic (bronchi, bronchioles, alveolar interstitial) regions, lymph nodes of both regions and lungs are considered as the source organs. The nine organs having high tissue weighting factors such as colon, lungs, stomach wall, breast, testis, urinary bladder, oesophagus, liver and thyroid and the compartments of the RT are considered as target organs. Eleven photon energies in the range of 15 keV to 4 MeV are considered for each source organ and the computed SAF values are presented in the form of tables. For the target organs in the proximity of the source organ including the source organ itself, the SAF values are relatively higher and decrease with increase in energy. As the distance between source and target organ increases, SAF values increase with energy and reach maxima depending on the position of the target organ with respect to the source organ. The SAF values are relatively higher for the target organs with smaller masses. Large deviations are seen in computed SAF values from the existing MIRD phantom data for most of the organs. These estimated SAF values play an important role in the estimation of equivalent dose to various target organs of a worker due to intake by inhalation pathway.


Assuntos
Carga Corporal (Radioterapia) , Pulmão/efeitos da radiação , Imagens de Fantasmas , Fótons , Radiometria/instrumentação , Fenômenos Fisiológicos Respiratórios , Adulto , Simulação por Computador , Elétrons , Humanos , Masculino , Método de Monte Carlo , Radiometria/métodos , Distribuição Tecidual , Contagem Corporal Total
16.
Radiat Prot Dosimetry ; 154(2): 148-56, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22914337

RESUMO

This paper describes a methodology to estimate embedded activity of (241)Am and Pu isotopes in a wound at an unknown depth. Theoretical calibration of an array of high-purity germanium detectors is carried out using the Monte Carlo code 'FLUKA' for a (241)Am source embedded at different depths in a soft tissue phantom of dimension 10 × 10 × 4 cm(3) simulating the palm of a worker. It is observed that, in the case of contamination due to pure (241)Am, the ratio of counts in 59.5 and 17.8 keV (Ratio 1) should be used to evaluate the depth, whereas the ratio of counts in 59.5 and 26.3 keV (Ratio 2) should be used when the contamination is due to a mixture of Pu and (241)Am compounds. Variations in the calibration factors (CFs) as well as in the Ratio 1 and Ratio 2 values are insignificant when source dimensions are varied from a point source to a 15-mm diameter circle. It is observed that tissue-equivalent polymethyl methacrylate material can be used in the phantom to estimate the embedded activity, when the activity is located at a depth of <1 cm, as the corresponding CFs do not show much variation with respect to those estimated using the phantom containing soft tissue material. In all other cases, an appropriate soft tissue-equivalent material should be used in the phantom for the estimation of CFs and ratios. The CFs thus obtained will be helpful in an accurate estimation of the depth of the wound and the activity embedded therein in the palm of a radiation worker.


Assuntos
Amerício/análise , Simulação por Computador , Mãos/efeitos da radiação , Método de Monte Carlo , Imagens de Fantasmas , Monitoramento de Radiação , Germânio , Mãos/patologia , Humanos , Fótons , Plutônio/análise
17.
Radiat Prot Dosimetry ; 148(4): 414-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21531750

RESUMO

Internal contamination due to high-energy photon (HEP) emitters is assessed using a scanning bed whole-body monitor housed in a steel room at the Bhabha Atomic Research Centre (BARC). The monitor consists of a (203 mm diameter × 102 mm thickness) NaI(Tl) detector and is calibrated using a Reference BOMAB phantom representative of an average Indian radiation worker. However, a series of different size physical phantoms are required to account for size variability in workers, which is both expensive and time consuming. Therefore, a theoretical approach based on Monte Carlo techniques has been employed to calibrate the system in scanning geometry with BOMAB phantoms of different sizes characterised by their weight (W) and height (H) for several radionuclides of interest ((131)I, (137)Cs, (60)Co and (40)K). A computer program developed for this purpose generates the detector response and the detection efficiencies (DEs) for the BARC Reference phantom (63 kg/168 cm), ICRP Reference male phantom (70 kg/170 cm) and several of its scaled versions. The results obtained for different size phantoms indicated a decreasing trend of DEs with the increase in W/H values of the phantoms. The computed DEs for uniform distribution of (137)Cs in BOMAB phantom varied from 3.52 × 10(-3) to 2.88 × 10(-3) counts per photon as the W/H values increased from 0.26 to 0.50. The theoretical results obtained for the BARC Reference phantom have been verified with experimental measurements. The Monte Carlo results from this study will be useful for in vivo assessment of HEP emitters in radiation workers of different physiques.


Assuntos
Fótons , Monitoramento de Radiação/métodos , Radiometria/métodos , Contagem Corporal Total/métodos , Estatura , Peso Corporal , Calibragem , Simulação por Computador , Desenho de Equipamento , Humanos , Índia , Masculino , Modelos Estatísticos , Método de Monte Carlo , Exposição Ocupacional , Aceleradores de Partículas , Imagens de Fantasmas , Monitoramento de Radiação/instrumentação , Radiometria/instrumentação , Valores de Referência , Contagem Corporal Total/instrumentação , Irradiação Corporal Total
18.
Radiat Prot Dosimetry ; 147(3): 406-16, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21147784

RESUMO

The adult reference male and female computational voxel phantoms recommended by ICRP are adapted into the Monte Carlo transport code FLUKA. The FLUKA code is then utilised for computation of dose conversion coefficients (DCCs) expressed in absorbed dose per air kerma free-in-air for colon, lungs, stomach wall, breast, gonads, urinary bladder, oesophagus, liver and thyroid due to a broad parallel beam of mono-energetic photons impinging in anterior-posterior and posterior-anterior directions in the energy range of 15 keV-10 MeV. The computed DCCs of colon, lungs, stomach wall and breast are found to be in good agreement with the results published in ICRP publication 110. The present work thus validates the use of FLUKA code in computation of organ DCCs for photons using ICRP adult voxel phantoms. Further, the DCCs for gonads, urinary bladder, oesophagus, liver and thyroid are evaluated and compared with results published in ICRP 74 in the above-mentioned energy range and geometries. Significant differences in DCCs are observed for breast, testis and thyroid above 1 MeV, and for most of the organs at energies below 60 keV in comparison with the results published in ICRP 74. The DCCs of female voxel phantom were found to be higher in comparison with male phantom for almost all organs in both the geometries.


Assuntos
Carga Corporal (Radioterapia) , Modelos Biológicos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Adulto , Simulação por Computador , Feminino , Humanos , Masculino , Especificidade de Órgãos , Doses de Radiação , Radiometria/métodos , Caracteres Sexuais
19.
Ann Thorac Surg ; 87(5): 1595-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19379917

RESUMO

Primary isolated chylopericardium is a rare condition with little known cause. This is the case of a 22-year-old woman in whom idiopathic chylopericardium developed. A lymphangiogram followed by a computed tomographic scan demonstrated occlusion of the thoracic duct and multiple lymphatic collaterals abutting the pericardial sac. Thoracic duct ligation resulted in the complete cure of the patient's condition. We theorized that the development of the pathologic lymphatic ducts in close proximity to the pericardium resulted in the development of the slowly accumulating chylopericardium.


Assuntos
Derrame Pericárdico/patologia , Ducto Torácico/cirurgia , Ecocardiografia , Feminino , Humanos , Linfografia , Dor , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/etiologia , Pericárdio/patologia , Síncope , Ducto Torácico/diagnóstico por imagem , Ducto Torácico/patologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
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