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1.
J Radiol Prot ; 44(2)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38834035

RESUMO

Nuclear medicine (NM) professionals are potentially exposed to high doses of ionising radiation, particularly in the skin of the hands. Ring dosimeters are used by the workers to ensure extremity doses are kept below the legal limits. However, ring dosimeters are often susceptible to large uncertainties, so it is difficult to ensure a correct measurement using the traditional occupational monitoring methods. An alternative solution is to calculate the absorbed dose by using Monte Carlo simulations. This method could reduce the uncertainty in dose calculation if the exact positions of the worker and the radiation source are represented in these simulations. In this study we present a set of computer vision and artificial intelligence algorithms that allow us to track the exact position of unshielded syringes and the hands of NM workers. We showcase a possible hardware configuration to acquire the necessary input data for the algorithms. And finally, we assess the tracking confidence of our software. The tracking accuracy achieved for the syringe detection was 57% and for the hand detection 98%.


Assuntos
Algoritmos , Medicina Nuclear , Exposição Ocupacional , Humanos , Exposição Ocupacional/análise , Mãos/efeitos da radiação , Método de Monte Carlo , Inteligência Artificial , Radiometria/métodos , Seringas
2.
J Radiol Prot ; 43(1)2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36720155

RESUMO

The International Commission on Radiation Units and Measurements (ICRU) proposed a new set of operational quantities for radiation protection for external radiation in its Report Committee 26 (ICRU95). The new proposal aims to improve the coherence between the operational quantities and the definitions of the protection quantities in the recommendations of the International Commission on Radiological Protection set out in 2007 (Ann. ICRP37). It is expected that this change in operational quantities will impact current dosimeter designs. Although for many photon energies, the conversion coefficients from physical field quantities to the new operational quantities will change relatively little, for radiation fields with low energy photon components, such as medical x-ray applications, there will be a significant decrease in the values of the conversion coefficients. This means that the numerical values of the new operational quantities will be much lower for the same radiation field. These values will be closer to the effective dose, but this change can still cause confusion for medical staff. It is important to examine the effect of the new set of dose conversion coefficients on the personal dose in realistic radiation fields. We performed a study to assess the effect of changing the definition of the operational quantity, personal dose equivalent (Hp), in realistic radiation fields in interventional radiology (IR) workplaces. The x-ray tube kilovoltage peak (kVp) in IR ranges between 60 and 120 kV. The medical staff is exposed to the scattered photons which have a wide range of energies depending on the beam configuration and the patient size. The objective of this study is to 'quantitatively' estimate the impact of implementing the new ICRU quantities of Report 95 in IR radiation fields using Monte Carlo simulations. Simulations of 560 different configurations in IR were performed using MCNPX to calculate fluence binned per energy and angle of incidence.HpandHp(10)were then calculated for each configuration using dose conversion coefficients from fluence given by ICRU Reports 95 and 57, respectively. The results show that the mean of the ratio,Hp(10)/Hp, is 1.6 for all simulated scenarios. This reduction will correct the current overestimation of the effective dose and should result in better compliance with the dose limits in IR. However, it may also have negative consequences on the safety culture among the medical staff. Special care will be needed when interpreting these lower doses.


Assuntos
Proteção Radiológica , Radiologia Intervencionista , Humanos , Doses de Radiação , Simulação por Computador , Proteção Radiológica/métodos , Fótons , Método de Monte Carlo , Radiometria/métodos
3.
Trop Anim Health Prod ; 55(3): 209, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37202581

RESUMO

The current study was conducted to evaluate the immunoenhancement effect of Moringa oleifera leaves alcoholic extract (MOLE) versus Oregano essential oil (OEO) against cyclophosphamide induced immunosuppression in broilers chicks. A total of a three hundred one-day-old chicks were assigned randomly into three main dietary groups, control, MOLE, and OEO for 14 days. After 14 days the three main experimental groups were subdivided into six groups, control, cyclophosphamide, MOLE, MOLE and Cyclophosphamide, OEO, and OEO and cyclophosphamide. Each group of these six groups was subdivided into three subgroups. Supplementation of broiler chicks with MOLE and OEO for 14 days significantly increased body weight compared to the control group. However, injection of broiler chicks with cyclophosphamide significantly induced body weight loss, impaired immunological response represented by decreasing total leukocytic count, differential leukocytic count, phagocytic activity, phagocytic index, and hemagglutinin inhibition titer for New Castle disease virus, lymphoid organs depletion, and increased the mortality rate. In contrast, supplementation of cyclophosphamide treated chicks with MOLE and OEO significantly reduced cyclophosphamide induced body weight loss and impaired immunological responses, as it showed significant increase in body weight, total leukocytic count, differential leukocytic count, phagocytic activity, phagocytic index, and hemagglutinin inhibition titer for New Castle disease virus, lymphoid organs proliferation, and reduced the mortality rate. This study indicated that MOLE and OEO supplementation ameliorated cyclophosphamide induced body weight loss and impaired immunological responses.


Assuntos
Moringa oleifera , Óleos Voláteis , Origanum , Animais , Óleos Voláteis/farmacologia , Galinhas , Adjuvantes Imunológicos/farmacologia , Hemaglutininas , Ciclofosfamida/toxicidade , Peso Corporal , Terapia de Imunossupressão/veterinária , Redução de Peso
4.
Transp Res Part A Policy Pract ; 148: 183-198, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33776251

RESUMO

Covid-19 seriously impacts and endangers lives of millions worldwide. To fight the spread of the virus, governments have taken various restricting measures including stay at home orders. Ultimately, the home delivery volume increased significantly, which still bears the risk of human-human infection during the final delivery. From a logisticians perspective, autonomous delivery vehicles (ADVs), which are a contactless delivery solution, have the potential to radically change the way groceries are delivered to customer homes and help to stop the spread of the virus. However, to date, research on user acceptance of ADVs is rare. This paper theoretically extends the Unified Theory of Acceptance and Use of Technology (UTAUT2) including gender as a moderator. The study is based on quantitative data collected in Germany through an online questionnaire (n = 501). Data were analysed using structural equation modelling. The results indicate that trust in technology, price sensitivity, innovativeness, performance expectancy, hedonic motivation, social influence, and perceived risk determine behavioural intention. However, some constructs are only significant for women. The findings of this paper have theoretical, managerial and policy contributions and implications within the areas of last-mile delivery and technology acceptance.

5.
Neuroophthalmology ; 45(5): 347-348, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483412

RESUMO

A 3-month-old boy was referred for assessment and management of apparently absent ocular globes. Ocular examination showed small orbits with apparently absent globes, small conjunctival cul-de-sac, shallow fornices, microblepharon and sunken eyelids. Magnetic resonance imaging of the orbit and brain revealed bilateral extreme microphthalmia, replacement of the optic nerves by disorganised rudimentary tissue tufts, hypoplastic orbits and extraocular muscles, an absent septum pellucidum and an absent corpus callosum. A pituitary hormonal essay showed decreased adrenocorticotropic hormone and thyroid-stimulating hormone. Septo-optic dysplasia has been rarely reported to be associated with microphthalmia. Timely treatment with hydrocortisone and levothyroxine is essential to prevent Addisonian crisis from the stress and pain that may accompany insertion of socket expanders.

6.
Foodborne Pathog Dis ; 13(6): 281-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26977940

RESUMO

Foodborne pathogens are leading causes of illness especially in developing countries. The current study aimed to characterize virulence-associated genes and antimicrobial resistance in 30 Salmonella Typhimurium isolates of chicken and human origin at Mansoura, Egypt. The results showed that invA, avrA, mgtC, stn, and bcfC genes were identified in all the examined isolates, while 96.7% and 6.7% were positive for sopB and pef genes, respectively. The highest resistance frequencies of the isolates were to chloramphenicol and trimethoprim-sulfamethoxazole (73.3%, each), followed by streptomycin (56.7%), tetracycline and ampicillin (53.3%, each), and gentamicin (30%). However, only 2.7% of the isolates were resistant to cefotaxime and ceftriaxone each. Different resistance-associated genes, including blaTEM, aadB, aadC, aadA1, aadA2, floR, tetA(A), tetA(B), and sul1, were identified in Salmonella Typhimurium isolates with the respective frequencies of 53.3%, 6.7%, 23.3%, 46.7%, 63.3%, 73.3%, 60%, 20%, and 96.7%. None of the isolates was positive for blaSHV, blaOXA, and blaCMY genes. The results showed that the intI1 gene was detected in 24 (80%) of the examined Salmonella Typhimurium isolates. Class 1 integrons were found in 19 (79.2%) isolates that were intI1 positive. Seven integron profiles (namely: P-I to P-VII) were identified with P-V (gene cassette dfrA15, aadA2), the most prevalent profile. To the best of our knowledge, this is the first study to characterize the unusual gene cassette array dfrA12-OrfF-aadA27 from Salmonella Typhimurium isolates in Egypt.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Microbiologia de Alimentos , Integrons , Carne/microbiologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/genética , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Galinhas , Egito/epidemiologia , Genes Bacterianos/genética , Humanos , Integrons/genética , Testes de Sensibilidade Microbiana/veterinária , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/epidemiologia , Salmonelose Animal/tratamento farmacológico , Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/patogenicidade , Virulência/genética
7.
Heliyon ; 10(5): e27005, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38495165

RESUMO

This paper explores the application of Set-based Design (SBD) in the design of a dates harvesting machine. Dates are a popular fruit with significant economic importance, especially in Saudi Arabia. However, the process of harvesting them is highly labour-intensive, and there is a need for an automated solution to improve efficiency and reduce costs. The study begins with a comprehensive review of the literature on other fruit-harvesting machines. The research then proposes an architectural design of a dates harvesting machine based on the understanding of the typical fruit harvesting machines. The dates harvesting machine design proposed in this study consists of several sub-assemblies. Each sub-assembly is designed as a set of alternatives, with different configurations of components, mechanisms and materials. The understanding of the customer requirements of typical date farms helped to identify the list of values that are essential to design the dates harvesting machine. These values were filtered and analysed using an analytical hierarchy process to define three key value attributes of 'design performance', 'safety' and 'cost'. The SBD approach helped to evaluate all the possible combinations of subsystems to identify the optimal solution that meets the customer's requirements and constraints. The SBD methodology resulted in the generation of 576 alternative design configurations which were aggressively narrowed down to 48 design solutions and then into 4 solutions where the final optimized design was selected using the PUGH matrix. The narrowing down is based on the combination of trade-off curves, solution performance and the identified key-value attributes. The proposed dates harvesting machine design shows great promise in improving the efficiency and sustainability of harvesting dates, and it can be adapted for use in agricultural applications.

8.
ACS Appl Mater Interfaces ; 14(9): 11727-11738, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35226459

RESUMO

Soft conductive elastomers with low hysteresis over a wide range of stretchability are desirable in various applications. Such applications include soft sensors with a long measurement range, motion recognition, and electronic skin, just to name a few. Even though the measurement capability of the sensors based on soft materials has been greatly improved compared to the traditional ones in recent years, hysteresis in the loading and unloading states has limited the applications of these sensors, thereby negatively affecting their accuracy and reliability. In this work, conductive elastomers with near-zero hysteresis have been formulated and fabricated using 3D printing. These elastomers are made by combining highly stretchable dielectric elastomer formulations with a polar hydrophobic ionic liquid and polymerizing under ultraviolet light. High-performance piezoresistive sensors have been fabricated and characterized, with a 10-fold stretchability and low hysteresis (1.2%) over long-term stability (more than 10 000 cycles under cyclic stress) with a 20 ms response time. Additionally, the current elastomers displayed fast mechanical and electrical self-healing properties. Using 3D printing in conjunction with some of our structural innovations, we have fabricated smart gloves to show this material's wide range of applications in soft robots, motion detection, wearable devices, and medical care.

9.
J Foot Ankle Res ; 15(1): 71, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104736

RESUMO

BACKGROUND: Diabetic foot ulcer (DFU) is one of the most serious diabetic complications. DFU is an open wound that usually occurs in the foot sole due to poor blood glucose control, peripheral neuropathy, and poor circulation. The human amniotic allograft membrane is a biological wound dressing derived from the amniotic membrane. It contains amino acids, nutrients, cytokines, and growth factors that make the growth process easier. OBJECTIVE: To compare dehydrated human amnion and chorion allograft (DHACA) plus the standard of wound care (SOC) with the SOC alone. METHODS: We searched for randomized clinical trials (RCTs) on PubMed, Scopus, Cochrane, and Web of Science till April 2021 using relevant keywords. All search results were screened for eligibility. We extracted the data from the included trials and pooled them as mean difference (MD) or risk ratio (RR) with the 95% confidence interval (CI) using Review Manager software (ver. 5.4). RESULTS: The pooled effect estimate from 11 RCTs showed that DHACA was superior to SOC regarding the complete wound healing in both 6th and 12th week (RR = 3.78; 95% CI: [2.51, 5.70]; P < 0.00001) and (RR = 2.00; 95% CI: [1.67, 2.39], P < 0.00001 respectively). Also, the analysis favored the DHACA regarding the mean time to heal in the 12th-week (MD = -12.07, 95%CI: [-19.23, -4.91], P = 0.001). The wound size reduction was better with DHACA (MD = 1.18, 95%CI: [-0,10, 2.26], P = 0.03). CONCLUSION: Using DHACA with SOC is safer and more effective than using SOC alone for DFU patients.


Assuntos
Diabetes Mellitus , Pé Diabético , Âmnio/transplante , Pé Diabético/terapia , Humanos , Padrão de Cuidado , Resultado do Tratamento , Cicatrização
10.
Phys Med ; 78: 58-70, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32947085

RESUMO

This paper presents the results of a parametric study on the occupational exposure in interventional radiology to explore the influence of various variables on the staff doses. These variables include the angiography beam settings: x-ray peak voltage (kVp), added copper filtration, field diameter, beam projection and source to detector distance. The study was performed using Monte-Carlo simulations with MCNPX for more than 5600 combinations of parameters that account for different clinical situations. Additionally, the analysis of the results was performed using both multiple and random forest regression to build a predictive model and to quantify the importance of each variable when the variables simultaneously change. Primary and secondary projections were found to have the most effect on the scatter fraction that reaches the operator followed by the effect of changing the x-ray beam quality. The effect of changing the source to image intensifier distance had the lowest effect.


Assuntos
Radiologia Intervencionista , Radiometria , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Doses de Radiação , Raios X
11.
Environ Sci Pollut Res Int ; 25(24): 23624-23630, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29959737

RESUMO

Breast cancer is the second most common fatal cancer in women. Developing a breast cancer is a multi-factorial and hormonal-dependent process, which may be triggered by many risk factors. An endocrine disrupting substance known as bisphenol A (BPA), that is used greatly in the manufacture of plastic products, was suggested as a possible risk factor for developing breast cancer. BPA has a strong binding affinity to non-classical membrane estrogen receptors like estrogen-related and G protein-coupled (GPER) receptors. Based on animal and in vitro studies, results showed a link between BPA exposure and increased incidence of breast cancer. BPA has the ability to alter multiple molecular pathways in cells namely, G protein-coupled receptor (GPER) pathway, estrogen-related receptor gamma (ERRγ) pathway, HOXB9 (homeobox-containing gene) pathway, bone morphogenetic protein 2 (BMP2) and (BMP4), immunoregulatory cytokine disturbance in the mammary gland, EGFR-STAT3 pathway, FOXA1 in ER-breast cancer cells, enhancer of zeste homolog 2 (EZH2), and epigenetic changes. Thus, the aforementioned alterations cause undesired gene stimulation or repression that increase risk of developing breast cancer. So, restricting exposure to BPA should be considered to aid in lowering the risk of developing breast cancer.


Assuntos
Compostos Benzidrílicos/toxicidade , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/metabolismo , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Animais , Compostos Benzidrílicos/metabolismo , Neoplasias da Mama/genética , Citocinas/metabolismo , Disruptores Endócrinos/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/metabolismo , Epigênese Genética , Feminino , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Fenóis/metabolismo , Plásticos/química , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Vector Borne Zoonotic Dis ; 16(3): 157-64, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26807798

RESUMO

Staphylococcus aureus in food is a consequence of inadequate hygienic handling and processing, posing a potential risk to public health. The current study aimed to characterize virulence factors, as well as antimicrobial resistance of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) isolated from retail chicken products and hand swabs from vendors in Egypt. In addition, genetic relatedness of the isolates from chicken and humans was evaluated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using protein A as a target. A total of 110 samples were collected from chicken products (n = 80) and vendors (n = 30). Overall, 30 (37.5%) chicken products samples were positive for S. aureus, whereas hand swabs from meat handlers revealed that 18 (60%) were positive. Ten MRSA strains were characterized by the presence of the mecA gene, comprising seven isolates from chicken and three from humans. Virulence-associated factors were evaluated by PCR, revealing that 31.3% of S. aureus isolates harbored the Panton-Valentine leukocidin (PVL) gene, whereas 10.4% were positive for the sea and sed genes each, and only two isolates were positive for γ-hemolysin-associated gene. Genotyping using spa PCR-RFLP showed identical restriction banding patterns of MRSA isolates of human and chicken meat origin, indicating the genetic relatedness of the isolates. To the best of our knowledge, this is the first study to characterize PVL-positive MRSA from chicken products and to utilize spa-RFLP for evaluating the genetic relatedness between MRSA of human and chicken origin in Egypt.


Assuntos
Galinhas/microbiologia , Microbiologia de Alimentos , Resistência a Meticilina/genética , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/genética , Fatores de Virulência/genética , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Egito/epidemiologia , Exotoxinas/genética , Genótipo , Humanos , Leucocidinas/genética , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Proteínas de Ligação às Penicilinas/genética , Aves Domésticas/microbiologia , Infecções Estafilocócicas/microbiologia , Proteína Estafilocócica A/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade
13.
Gut Pathog ; 8(1): 42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27625705

RESUMO

BACKGROUND: Hepatitis C virus (HCV) causes debilitating liver diseases, which may progress to cirrhosis and cancer, and claims 500,000 annual lives worldwide. While HCV epidemiology, pathophysiology, and therapy are being deeply studied, rare attention is given to reciprocal interactions between HCV infection , HCV-induced chronic liver diseases, and the human gut microbiome. As Egypt has the world's highest prevalence of HCV infections, we launched this study to monitor differences in the gut microbial community composition of Egyptian HCV patients that may affect, or result from, the patients' liver state. RESULTS: To this end, we analyzed stool samples from six stage 4-HCV patients and eight healthy individuals by high-throughput 16S rRNA gene sequencing using Illumina MiSeq. Overall, the alpha-diversity of the healthy persons' gut microbiomes was higher than those of the HCV patients. Whereas members of phylum Bacteroidetes were more abundant in HCV patients, healthy individuals had higher abundance of Firmicutes, Proteobacteria, and Actinobacteria. Genus-level analysis showed differential abundance of Prevotella and Faecalibacterium (higher in HCV patients) vs. Ruminococcus and Clostridium (healthy group), indicating that the higher abundance of Bacteroidetes in HCV patients is most likely due to Prevotella overabundance. The probiotic genus, Bifidobacterium, was only observed in the microbiotas of healthy individuals. CONCLUSIONS: To the best of our knowledge, this study provides a first overview of major phyla and genera differentiating stage 4-HCV patients from healthy individuals and suggests possible microbiome remodeling in chronic hepatitis C, possibly shaped by bacterial translocation as well as the liver's impaired role in digestion and protein synthesis. Future studies will investigate the microbiome composition and functional capabilities in more patients while tracing some potential biomarker taxa (e.g., Prevotella, Faecalibacterium vs. Bifidobacterium).

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