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1.
Heliyon ; 10(1): e23848, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192836

RESUMO

Pristine ZrO2 and doped with different concentrations of Copper (0-7 %) were synthesized using a sol-gel combustion route. Several advanced techniques like XRD, EDX, TEM, XPS, P.L., and UV-vis spectrophotometer have characterized the compositions. The XRD proved that all peaks matched with a tetragonal phase of ZrO2 without any impurities of other phases. An average crystallite size rises from 20 to 55 nm by increasing the concentrations of Copper. The elemental analysis was examined by EDX and confirmed the presence of Cooper, Zirconium, and Oxygen. The red shift was observed due to a decrease in the bandgap (5.5-4.01 eV) with increasing the Cu concentrations. From the analysis of photocatalysis of pure ZrO2 and different concentrations of Cu-doped ZrO2 for M.B., RHB, and mix of them. The increase in doping of Cu led to enhancing the performance of the removing MB from 35 to 80 %, however, the RHB degradation was from 42 to 81 % while the mix of M.B. and RHB reached 85 % with 7 % Cu-doping ZrO2.

2.
Int J Neurosci ; : 1-5, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37548488

RESUMO

Behcet's disease is a chronic polysymptomatic systemic vasculitis disorder of unknown etiology characterized by several clinical manifestations in multiple organ systems. Involvement of the nervous system occurs in ∼9% of patients with Behcet's disease (ranging from 3 to 30%). Neuro-Behcet's disease is a great masquerader of multiple sclerosis. Diagnosing this disorder might be challenging, especially in a patient who does not fulfill the criteria of Behcet's disease while having a neurological presentation. We report a case of neuro-Behcet's disease who was misdiagnosed as having multiple sclerosis for many years and started on unnecessary disease-modifying therapy for multiple sclerosis. A thorough history, physical examination, and systematic investigations are mandatory to differentiate between these two conditions. Our case presentation raises awareness of the importance of differentiating between these two conditions since the consequences of misdiagnosis are catastrophic. The main challenges differentiating between multiple sclerosis and neuro-Behcet's are clinical and paraclinical, including neuroimaging.

3.
J Neurosci Rural Pract ; 14(2): 371-373, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181160

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary syndrome caused by heterozygous mutations in the NOTCH3 gene that manifests in adulthood and is characterized by recurrent transient ischemic attacks and strokes, migraine-like headaches, psychiatric disturbance, and progressive dementia. The current study reports an interesting case of CADASIL in a Saudi patient with a heterozygous mutation in exon 18 of the NOTCH3 gene presenting only with cognitive decline without migraine or stroke. The diagnosis was suspected mainly because of the typical brain magnetic resonance imaging (MRI) features that led to performing genetic testing to confirm the diagnosis. This illustrates the importance of brain MRI in the diagnosis of CADASIL. Increased awareness of neurologists and neuroradiologists about the typical MRI features of CADASIL is of paramount importance to reach the diagnosis in a timely manner. Awareness of the atypical presentations of CADASIL will lead to identifying more CADASIL cases.

4.
Materials (Basel) ; 16(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37048969

RESUMO

Iron-doped Zinc oxide nanoparticles were produced by the sol-gel combustion method. This study aims to see how iron doping affects the structural, optical, and photocatalytic characteristics of ZnO composites. XRD examined all samples to detect the structural properties and proved that all active materials are a single hexagonal phase. The morphology and particle size were investigated by TEM. Computational Density functional theory (DFT) calculation of the band structure, density of state, and charge distributions for ZnO were investigated in comparison with ZnO dope iron. We reported the application results of ZnO doped Fe for Methylene blue dye removal under photocatalytic degradation effect. The iron concentrations affect the active material's band gap, producing higher photocatalytic performance. The acquired results could be employed to enhance the photocatalytic properties of ZnO.

5.
Molecules ; 28(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36903399

RESUMO

Mesenchymal stem cells (MSCs) have newly developed as a potential drug delivery system. MSC-based drug delivery systems (MSCs-DDS) have made significant strides in the treatment of several illnesses, as shown by a plethora of research. However, as this area of research rapidly develops, several issues with this delivery technique have emerged, most often as a result of its intrinsic limits. To increase the effectiveness and security of this system, several cutting-edge technologies are being developed concurrently. However, the advancement of MSC applicability in clinical practice is severely hampered by the absence of standardized methodologies for assessing cell safety, effectiveness, and biodistribution. In this work, the biodistribution and systemic safety of MSCs are highlighted as we assess the status of MSC-based cell therapy at this time. We also examine the underlying mechanisms of MSCs to better understand the risks of tumor initiation and propagation. Methods for MSC biodistribution are explored, as well as the pharmacokinetics and pharmacodynamics of cell therapies. We also highlight various promising technologies, such as nanotechnology, genome engineering technology, and biomimetic technology, to enhance MSC-DDS. For statistical analysis, we used analysis of variance (ANOVA), Kaplan Meier, and log-rank tests. In this work, we created a shared DDS medication distribution network using an extended enhanced optimization approach called enhanced particle swarm optimization (E-PSO). To identify the considerable untapped potential and highlight promising future research paths, we highlight the use of MSCs in gene delivery and medication, also membrane-coated MSC nanoparticles, for treatment and drug delivery.


Assuntos
Células-Tronco Mesenquimais , Nanopartículas , Distribuição Tecidual , Sistemas de Liberação de Medicamentos/métodos , Citoplasma
6.
J Multidiscip Healthc ; 15: 1747-1757, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016857

RESUMO

Background: Iterative reconstruction algorithm (IR) techniques were developed to maintain a lower radiation dose for patients as much as possible while achieving the required image quality and medical benefits. The main purpose of the current research was to assess the level and usage extent of IR techniques in computed tomographic (CT) scan exams. Also, the obligation of practitioners in several hospitals in Saudi Arabia to implement IR in CT exams was assessed. Material and Methodology: The recent research was based on two studies: data collection and a survey study. Data on the CT scan examinations were retrospectively collected from CT scanners. The survey was conducted using a questionnaire to evaluate radiographers' and radiologists' perceptions about IR and their practices with IR techniques. The statistical analysis results were performed to measure the usage strength level of IR methods. Results and Discussions: The IR strength level of 50% was selected for nearly 80% of different CT examinations and patients of different ages and weights. About 46% of the participants had not learned about IR methods during their college studies, and 54% had not received formal training in applying IR techniques. Only 32% of the participants had adequate experience with IR. Half of the participants were not involved in the updating process of the CT protocol. Conclusion: The results indicate that the majority of radiographer and radiologist at four different hospitals in Saudi Arabia have no explicit or understandable knowledge of selecting IR strength levels during the CT examination of patients. There is a need for more training in IR applications for both radiologists and radiographers. Training sessions were suggested to support radiographers and radiologists to efficiently utilize IR techniques to optimize image quality. Further studies are required to adjust CT exam protocols effectively to utilize the IR technique.

7.
Infect Drug Resist ; 15: 1175-1189, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35345472

RESUMO

Heart attacks, arrhythmias, and cardiomyopathy are all linked to the 2019 coronavirus disease (COVID-19), which has been identified as a risk factor for cardiovascular disease. Nothing can be held accountable in the current state of affairs. Undiagnosed chronic systolic heart failure (CSHF) develops when the heart's second half of the cardiac cycle does not function properly. As a result, the heart's blood pumping function is interrupted. Stress-induced cardiomyopathy may be caused by a variety of factors inside the body (SICM). Cytokine storm and microvascular dysfunction are among the issues. There is inflammation in the heart muscle, which may lead to stress-induced cardiomyopathy. A major part of our study is going to be devoted to understanding the effects of coronavirus on the cardiovascular system and blood vessels. A lot of time and effort has been put into figuring out the health effects of radiation exposure. The heart and circulatory system are shown to be affected by the coronavirus in this research. COVID-19 is shown to influence persons with heart disease, heart failure, arrhythmias, microvascular angiopathy, and cardiac damage in this study.

8.
J. physiol. biochem ; 78(1): 151-168, feb. 2022.
Artigo em Inglês | IBECS | ID: ibc-215880

RESUMO

This study examined whether astaxanthin (ASX) could alleviate hepatic steatosis in rats fed a high-fat diet (HFD) by modulating the nuclear factor erythroid 2-related factor 2 (Nrf2)/miR-21 axis. Rats (n = 8/group) were fed either a standard diet (3.8 kcal/g; 10% fat) or HFD (4.6 kcal/g; 40% fat) and treated orally with either the vehicle or ASX (6 mg/kg) daily for 8 days. Another group was fed HFD and treated with ASX and brusatol (an Nrf2 inhibitor) (2 mg/kg/twice per week/i.p.). ASX prevented the gain in body and liver weights and attenuated hepatic lipid accumulation in HFD-fed rats. In the control and HFD-fed rats, ASX did not affect food intake, serum free fatty acid (FFA) content, and glucose and insulin levels and tolerance. However, serum triglyceride (TG), cholesterol, and low-density lipoprotein-cholesterol levels; hepatic levels of TGs and FFAs; and hepatic levels of Srebp1, Srebp2, HMGCR, and fatty acid synthase mRNAs and miR-21 were reduced and the mRNA levels of Pparα were significantly increased in both the groups. These effects were associated with a reduction in the hepatic levels of reactive oxygen species, malondialdehyde, tumor necrosis factor-α, and interlukin-6 as well as an increase in superoxide dismutase levels, total glutathione content, and nuclear levels and activity of Nrf2. miR-21 levels were strongly correlated with the nuclear activity of Nrf2. Brusatol completely reversed the effects of ASX. In conclusion, ASX prevents hepatic steatosis mainly by transactivating Nrf2 and is associated with the suppression of miR-21 and Srebp1/2 and upregulation of Pparα expression. (AU)


Assuntos
Animais , Ratos , Hepatopatia Gordurosa não Alcoólica , MicroRNAs , Dieta Hiperlipídica , Fígado/metabolismo , Fator 2 Relacionado a NF-E2 , Ativação Transcricional , Xantofilas
9.
J Physiol Biochem ; 78(1): 151-168, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34651285

RESUMO

This study examined whether astaxanthin (ASX) could alleviate hepatic steatosis in rats fed a high-fat diet (HFD) by modulating the nuclear factor erythroid 2-related factor 2 (Nrf2)/miR-21 axis. Rats (n = 8/group) were fed either a standard diet (3.8 kcal/g; 10% fat) or HFD (4.6 kcal/g; 40% fat) and treated orally with either the vehicle or ASX (6 mg/kg) daily for 8 days. Another group was fed HFD and treated with ASX and brusatol (an Nrf2 inhibitor) (2 mg/kg/twice per week/i.p.). ASX prevented the gain in body and liver weights and attenuated hepatic lipid accumulation in HFD-fed rats. In the control and HFD-fed rats, ASX did not affect food intake, serum free fatty acid (FFA) content, and glucose and insulin levels and tolerance. However, serum triglyceride (TG), cholesterol, and low-density lipoprotein-cholesterol levels; hepatic levels of TGs and FFAs; and hepatic levels of Srebp1, Srebp2, HMGCR, and fatty acid synthase mRNAs and miR-21 were reduced and the mRNA levels of Pparα were significantly increased in both the groups. These effects were associated with a reduction in the hepatic levels of reactive oxygen species, malondialdehyde, tumor necrosis factor-α, and interlukin-6 as well as an increase in superoxide dismutase levels, total glutathione content, and nuclear levels and activity of Nrf2. miR-21 levels were strongly correlated with the nuclear activity of Nrf2. Brusatol completely reversed the effects of ASX. In conclusion, ASX prevents hepatic steatosis mainly by transactivating Nrf2 and is associated with the suppression of miR-21 and Srebp1/2 and upregulation of Pparα expression.


Assuntos
MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ratos , Ativação Transcricional , Xantofilas
10.
Polymers (Basel) ; 13(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34833310

RESUMO

The lung is a vital organ that houses the alveoli, which is where gas exchange takes place. The COVID-19 illness attacks lung cells directly, creating significant inflammation and resulting in their inability to function. To return to the nature of their job, it may be essential to rejuvenate the afflicted lung cells. This is difficult because lung cells need a long time to rebuild and resume their function. Biopolymeric particles are the most effective means to transfer developing treatments to airway epithelial cells and then regenerate infected lung cells, which is one of the most significant symptoms connected with COVID-19. Delivering biocompatible and degradable natural biological materials, chemotherapeutic drugs, vaccines, proteins, antibodies, nucleic acids, and diagnostic agents are all examples of these molecules' usage. Furthermore, they are created by using several structural components, which allows them to effectively connect with these cells. We highlight their most recent uses in lung tissue regeneration in this review. These particles are classified into three groups: biopolymeric nanoparticles, biopolymeric stem cell materials, and biopolymeric scaffolds. The techniques and processes for regenerating lung tissue will be thoroughly explored.

11.
J Food Biochem ; 45(11): e13945, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34585409

RESUMO

This study examined if the aqueous extract of Crataegus aronia (C. aronia) can prevent high-fat diet (HFD)-induced hepatic steatosis in rats by activating AMPK. Adult male Wistar rats were fed either a control diet or HFD for 12 weeks and treated either with vehicle (normal saline) or C. aronia extract (200 mg/kg/orally), daily. Also, hepatocytes were treated with increasing concentrations of the extract in the presence or absence of compound C (CC), an AMPK inhibitor. C. aronia prevented the increase in serum and hepatic lipids, reduced hepatic levels of reactive oxygen species, and increased hepatic glutathione and superoxide dismutase levels. It also downregulated the hepatic expression of SREBP1/2, fatty acid synthase, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase but stimulated the activity of AMPK and levels of peroxisome proliferator-activated receptor-alpha. Similar effects were reported in the cultured cells, in a dose-dependent manner but were prevented by CC. In conclusion, C. aronia ameliorates HFD-induced hepatic steatosis and oxidative stress by activating AMPK. PRACTICAL APPLICATIONS: The use of the aqueous extract of Crataegus aronia has been extensively used during the last years in traditional medicine to treat chronic disorders including nonalcoholic fatty liver disease. The findings of this study support these findings and suggest that oral administration of C. aronia aqueous extract has potent hypoglycemic effect and demonstrate the mechanism of action mimics such drugs such as metformin and involves activation of AMPK and peroxisome proliferator-activated receptor-alpha. These findings are very encouraging for further biochemical analysis and isolation of active ingredients responsible for these effects to be used in more clinical trials.


Assuntos
Crataegus , Hepatopatia Gordurosa não Alcoólica , Photinia , Proteínas Quinases Ativadas por AMP , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , PPAR alfa/genética , Ratos , Ratos Wistar
12.
Saudi J Biol Sci ; 28(3): 1966-1977, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33732083

RESUMO

This study evaluated the effect of Crataegus aronia (C. aronia) aqueous extract on cardiac substrate utilization and insulin signaling in adult male healthy Wistar rats. Rats (n = 18/group) were either administered normal saline (vehicle) or treated with C. aronia aqueous extract (200 mg/kg) for 7 days, daily. Fasting plasma glucose and insulin levels were not significantly changed in C. aronia-treated rats but were significantly reduced after both the intraperitoneal glucose or insulin tolerance tests. Besides, C. aronia significantly increased the left ventricular (LV) activities of phosphofructokinase (PFK) and pyruvate dehydrogenase (PDH), two markers of glycolysis and glucose oxidation, respectively, and suppressed the levels of pyruvate dehydrogenase kinase 4 (PDK4), an inhibitor of PDH. Concomitantly, it significantly reduced the LV levels of carnitine palmitoyltransferase 1 (CPT1) and PPARα, two markers of fatty acid (FAs) oxidations. Under basal and insulin stimulation, C. aronia aqueous extract boosted insulin signaling in the LV of rats by increasing the protein levels of p-IRS (Tyr612) and p-Akt (Ser473) and suppressing protein levels of p-mTOR (Ser 2448) and p-IRS (Ser307). In parallel, C. aronia also increased the protein levels of GLUT-4 in the membrane fraction of the treated LVs. All these effects were also associated with a significant increase in AMPK activity (phosphorylation at Thr172), a major energy modulator that stimulates glucose utilization. In conclusion, short-term administration of C. aronia aqueous extract shifts the cardiac metabolism toward glucose utilization, thus making this plant a potential therapeutic medication in cardiac disorders with impaired metabolism.

13.
J Xray Sci Technol ; 28(6): 1025-1035, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986646

RESUMO

BACKGROUND: Computed Tomographic (CT) imaging procedures have been reported as the main source of radiation in diagnostic procedures compared to other modalities. To provide the optimal quality of CT images at the minimum radiation risk to the patient, periodic inspections and calibration tests for CT equipment are required. These tests involve a series of measurements that are time consuming and may require specific skills and highly-trained personnel. OBJECTIVE: This study aims to develop a new computational tool to estimate the dose of CT radiation outputs and assist in the calibration of CT scanners. It may also provide an educational resource by which radiological practitioners can learn the influence of technique factors on both patient radiation dose and the produced image quality. METHODS: The computational tool was developed using MATLAB in order to estimate the CT radiation dose parameters for different technique factors. The CT radiation dose parameters were estimated from the calibrated energy spectrum of the x-ray tube for a CT scanner. RESULTS: The estimated dose parameters and the measured values utilising an Adult CT Head Dose Phantom showed linear correlations for different tube voltages (80 kVp, 100 kVp, 120 kVp, and 140 kVp), with R2 nearly equal to 1 (0.99). The maximum differences between the estimated and measured CTDIvol were under 5 %. For 80 kVp and low tube currents (50 mA, 100 mA), the maximum differences were under 10%. CONCLUSIONS: The prototyped computational model provides a tool for the simulation of a machine-specific spectrum and CT dose parameters using a single dose measurement.


Assuntos
Tomada de Decisões Assistida por Computador , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Adulto , Cabeça/diagnóstico por imagem , Humanos
14.
Med Sci (Basel) ; 8(3)2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32698332

RESUMO

Computed tomography (CT) is a key imaging technique in diagnostic radiology, providing highly sensitive and specific information. While its use has increased dramatically in recent years, the quantity and associated risks of radiation from CT scans present major challenges, particularly in paediatrics. The fundamental principles of radiation protection require that radiation quantities be as low as reasonably achievable and CT use must be justified, particularly for paediatric patients. CT radiation knowledge is a key factor in optimising and minimising radiation risk. The objective of this study was to analyse knowledge level, expertise, and competency regarding CT radiation dose and its hazards in paediatrics among radiologists in Saudi Arabian hospitals. A self-reported, multiple-choice questionnaire assessed the attitudes and opinions of radiologists involved in imaging studies using ionising radiation. Among the total respondents, 65% ± 13.5% had a good comprehension of the dangers of carcinogenicity to the patient resulting from CT scans, with 80% presuming that cancer risks were elevated. However, only 48.5%, 56.5%, and 65% of the respondents were aware of specific radiation risks in head, chest, and abdominal paediatric examinations, respectively. Regular, frequent, and specific training courses are suggested to improve the fundamental knowledge of CT radiation among radiologists and other physicians.

15.
Med Sci (Basel) ; 8(3)2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640553

RESUMO

Background: To evaluate contrast-to-noise ratio (CNR) measurements in assessing image quality, in the context of the detectability performance of low-contrast detail (LCD), in computed tomography (CT) images, since exposure to elevated ionising-type radiation is considered to present excessive carcinogenic risk, whilst also causing distress in study subjects. Methods: An LCD phantom module (CTP515) was utilised in the study. Three dissimilar contrast items were used to analyse the ramifications of the proportions of an object on the CNR. Three multidetector CT (MDCT) scanners were used, with 16-MDCT, 64-MDCT and 80-MDCT frameworks, respectively. The CT scans were recreated using three dissimilar remaking algorithms-soft, standard and lung. The effects exerted on the CNR by various remodelling algorithms, as well as the contrast of various objects along with the size of the objects, were explored. The Hounsfield units of each chosen object (one unit representing the outer portion of the object) and the background and the standard deviation of the noise parameter were quantified, and algorithms were developed using MATLAB. Results: The CNR information was greatly influenced by changing the image recreation calculations and was very much increased in the soft-tissue recreation images using 16-MDCT and 64-MDCT. The CNR information was also increased more in the optimum recreation images than in the reproduced images from the computational procedure used in the 80-MDCT. The results did not show any remarkable contrasts in the CNR values between the different object sizes. Overall, a higher kVp produced an improved CNR in all the CT scanners. In particular, there were prominent upgrades in the CNR information when the kVp was increased from 80 to 120. Higher mAs levels gave better CNR values overall, especially for greater section thicknesses. Based on the CNR estimations, the 64-MDCT provided the best correlation among the CT scanners. Conclusions: The objective LCD appraisal method, based on CNR measurements, was confirmed as being useful for checking the different impacts of kVp, mAs and section thickness on the nature of the picture. This procedure was similarly viable in assessing the impacts of the different reconstruction calculations and the different differentiation questions on the nature of the image.

16.
J Med Imaging Radiat Sci ; 47(3): 235-242, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31047288

RESUMO

PURPOSE: To evaluate the impact of patient centering and radiation dose during intracranial computed tomography (ICT) on quantitative and qualitative image quality. MATERIALS AND METHODS: A total of 500 consecutive patients who underwent ICT were retrospectively reviewed using a 128-slice CT scanner (Definition AS+, Siemens, Germany). Patients were subjected in equal numbers to one of two positioning protocols: group A, poorly centered; and group B involved accurate centering before imaging. Gray-white matter (GWM) conspicuity, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) in each group were calculated. Qualitative image quality in terms of GWM differentiation, distinctness of posterior fossa contents, and overall diagnostic acceptability were evaluated by 2 neuroradiologists. The dose length product, CNR, SNR, and noise were measured between each group and data generated were compared using Mann-Whitney U nonparametric statistics. Visual grading characteristic and Kappa analyses were performed. RESULTS: The mean noise index was significantly lower in group B (2.61 ± 0.29) compared with A (2.66 ± 0.21; P < .02). The mean attenuation of GWM, SNR, and CNR in the frontal lobe (A, 1:0.77, 0.84, 8.70 ± 1.36; and B, 1:0.65, 0.85, 15.32 ± 1.21; P < .02), occipital lobe (A, 1:1.10, 1.18, 10.79±2.11; and B, 1:0.94, 0.64, 14.41 ± 3.09; P < .04), and cerebellum (A, 1:0.79, 0.90, 12.56 ± 4.08; and B, 1:0.82, 0.87, 14.07 ± 2.28; P < .04) were significantly higher in group B compared with A, while the globus pallidus, caudate nucleus, and optic track in the basal ganglia demonstrated no difference in each group (P > .05). Mean dose length product demonstrated no significance between each group (A, 1312.03 ± 133.92; B, 1298.11 ± 130.61). The qualitative analyses demonstrated significant increases in visual grading characteristic for each reader (P < .02) and interobserver agreement was significantly increased in protocol B (k = 0.81) compared with A (k = 0.62). CONCLUSIONS: Correct patient centering increases the CNR and SNR in both GWM in the left and right hemispheres of the brain during ICT.

17.
World J Radiol ; 6(1): 1-6, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24578786

RESUMO

Computed tomography (CT) has earned a well-deserved role in diagnostic radiology, producing cross-sectional and three-dimensional images which permit enhanced diagnosis of many pathogenic processes. The speed, versatility, accuracy, and non-invasiveness of this procedure have resulted in a rapid increase in its use. CT imaging, however, delivers a substantially higher radiation dose than alternative imaging methodologies, particularly in children due to their smaller body dimensions. In addition, CT use in children produces an increased lifetime risk of cancer, as children's developing organs and tissues are inherently more vulnerable to cellular damage than those of adults. Though individual risks are small, the increasing use of CT scans in children make this an important public health problem. Various organizations have recommended measures to minimize unnecessary exposures to radiation through CT scanning. These include elimination of multiple or medically unnecessary scans, development of patient-specific dosing guidelines, and use of alternative radiographic methodology wherever possible. Another important factor in excessive CT exposures, however, is a documented lack of awareness among medical practitioners of the doses involved in CT usage as well as its significant potential dangers. This review examines the effects of paediatric CT radiation, discusses the level of medical practitioner awareness of these effects, and offers recommendations on alternative diagnostic methods and practitioner education.

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