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1.
Nat Immunol ; 18(12): 1353-1360, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29058702

RESUMO

The polarization of leukocytes toward chemoattractants is essential for the directed migration (chemotaxis) of leukocytes. How leukocytes acquire polarity after encountering chemical gradients is not well understood. We found here that leukocyte polarity was generated by TIPE2 (TNFAIP8L2), a transfer protein for phosphoinositide second messengers. TIPE2 functioned as a local enhancer of phosphoinositide-dependent signaling and cytoskeleton remodeling, which promoted leading-edge formation. Conversely, TIPE2 acted as an inhibitor of the GTPase Rac, which promoted trailing-edge polarization. Consequently, TIPE2-deficient leukocytes were defective in polarization and chemotaxis, and TIPE2-deficient mice were resistant to leukocyte-mediated neural inflammation. Thus, the leukocyte polarizer is a dual-role phosphoinositide-transfer protein and represents a potential therapeutic target for the treatment of inflammatory diseases.


Assuntos
Quimiotaxia de Leucócito/genética , Encefalomielite Autoimune Experimental/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Linfócitos T/imunologia , Animais , Polaridade Celular/genética , Quimiotaxia de Leucócito/fisiologia , Inflamação/genética , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositóis/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas rac de Ligação ao GTP/antagonistas & inibidores
2.
Cell Biochem Funct ; 41(5): 517-541, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37282756

RESUMO

Hyperglycemia, a distinguishing feature of diabetes mellitus that might cause a diabetic foot ulcer (DFU), is an endocrine disorder that affects an extremely high percentage of people. Having a comprehensive understanding of the molecular mechanisms underlying the pathophysiology of diabetic wound healing can help researchers and developers design effective therapeutic strategies to treat the wound healing process in diabetes patients. Using nanoscaffolds and nanotherapeutics with dimensions ranging from 1 to 100 nm represents a state-of-the-art and viable therapeutic strategy for accelerating the wound healing process in diabetic patients, particularly those with DFU. Nanoparticles can interact with biological constituents and infiltrate wound sites owing to their reduced diameter and enhanced surface area. Furthermore, it is noteworthy that they promote the processes of vascularization, cellular proliferation, cell signaling, cell-to-cell interactions, and the formation of biomolecules that are essential for effective wound healing. Nanomaterials possess the ability to effectively transport and deliver various pharmacological agents, such as nucleic acids, growth factors, antioxidants, and antibiotics, to specific tissues, where they can be continuously released and affect the wound healing process in DFU. The present article elucidates the ongoing endeavors in the field of nanoparticle-mediated therapies for the management of DFU.


Assuntos
Diabetes Mellitus , Pé Diabético , Nanopartículas , Humanos , Pé Diabético/tratamento farmacológico , Cicatrização , Peptídeos e Proteínas de Sinalização Intercelular , Nanopartículas/uso terapêutico , Nanotecnologia , Diabetes Mellitus/tratamento farmacológico
3.
Br J Nutr ; 125(9): 1007-1016, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32493523

RESUMO

Studies have revealed that the timing of macronutrient ingestion may influence body weight and glucose tolerance. We aimed to examine the effect of high protein v. high carbohydrate intake at the evening meal on metabolic parameters of patients with type 2 diabetes. This is a single-blinded, parallel, randomised controlled trial. Ninety-six patients with type 2 diabetes, aged 32-65 years with a mean BMI of 28·5 (sd 3·4) kg/m2, were randomly assigned into one of these three groups: standard evening meal (ST), high-carbohydrate evening meal (HC) and high-protein evening meal (HP). Then, the patients were followed for 10 weeks. HbA1c, fasting blood glucose, fasting insulin, insulin resistance, TAG, LDL-cholesterol, VLDL-cholesterol, diastolic blood pressure, body weight, body fat percentage and waist circumference decreased significantly in all three groups (P < 0·05). HbA1c showed more improvement in the ST compared with the HP group (-0·45 (sd 0·36) v. -0·26 (sd 0·36)). Reductions in BMI and body weight were significantly higher in the ST compared with the HP group (P < 0·05). Reductions in total cholesterol, non-HDL-cholesterol and systolic blood pressure were significant in all groups, except for the HP group. Non-HDL-cholesterol:HDL-cholesterol remained unchanged in all groups. The results of the present study revealed that even distribution of carbohydrates and protein among meals compared with reducing carbohydrates and increasing protein at dinner may have a more beneficial effect on glycaemic control of patients with type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Refeições , Adulto , Idoso , Pressão Sanguínea , Colesterol/sangue , Ingestão de Energia , Exercício Físico , Feminino , Hemoglobinas Glicadas/análise , Controle Glicêmico , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
4.
Cost Eff Resour Alloc ; 19(1): 15, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33676529

RESUMO

BACKGROUND AND OBJECTIVE: Saving blood products is an important public health issue especially in developing countries with limited financial resources. We aimed to suggest a new hypothetical model to make a change in the current blood transfusion policy in the newborn intensive care unit (NICU) to reduce wastage of blood supplies as well as the risk of exposure to multiple donors. METHODS: In this cross-sectional study, all transfused neonates (n = 70) who were admitted to NICU of Nemazee Hospital, a tertiary referral hospital in Southern Iran, were evaluated between March and June 2019. Based on the information of neonates' transfusion during this study period and determined transfusion indices, a specific pediatric pack was suggested and the related total costs per transfusion, as well as the donor-exposure rate of the hypothetical and the current transfusion method, were compared. RESULTS: Considering the mean number of transfusions per neonate: 4 and mean volume of transfused packed red cells: 20 ml per transfusion, the cost-analysis of pediatric and the adult pack was presented. Arithmetically, we proved a higher total cost per transfusion for using adult pack comparing to pediatric pack. Additionally, using a pediatric pack set leads to a 24% reduction in RBCs wastage per transfusion and a 68.13% reduction in donor-exposure rate. CONCLUSIONS: The assignment of a dedicated pediatric pack for neonates will be able to improve the cost-effectiveness by a substantial reduction in donor-exposure rate and blood wastage. This finding should be taken into consideration to generate economic growth and make improvements in child health status.

5.
BMC Endocr Disord ; 20(1): 162, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33121469

RESUMO

BACKGROUND: Accumulating evidence suggests that low vitamin D status may affect male gonadal structure. This study was undertaken to reveal whether vitamin D-deficient rats have demonstrable changes in the quantitative histomorphometric properties of the testis. METHODS: In the present investigation, adult male Sprague-Dawley rats were divided into four groups and received: group 1) conventional diet; group 2) vitamin D-deficient diet; group 3) vitamin D-deficient diet and paricalcitol and group 4) conventional diet plus paricalcitol. After 3 months, serum levels of vitamin D metabolites, Ca, P, LH, FSH, testosterone, and epididymal sperm quality were evaluated. Moreover, the morphometric characteristics of testis were assessed via stereological methods. RESULTS: Rats fed a vitamin D-deficient diet (groups 2 and 3) were normocalcemic and had 25-hydroxyvitamin D3 level below 10 ng/mL. A significant reduction in serum testosterone and comparable gonadotropin levels were seen in vitamin D-deficient groups compared to controls. The concentration, morphology, and motility of sperm cells were profoundly disturbed in animals raised on the vitamin D-deficient diet. There was a significant decline in the population of different germ cells, the volume of interstitial tissue and germinal epithelium in group 2 and 3 rats, which were placed on the vitamin D-deficient diet. No appreciable difference in the estimates of the Leydig or Sertoli cell numbers were observed between groups. CONCLUSIONS: The depletion of vitamin D stores and induction of moderate grades of vitamin D deficiency by dietary measures led to remarkable impairment of spermatogenesis and microscopic architecture of rat testis. These findings can be attributed, at least in part, to decreased androgen production.


Assuntos
Testículo/patologia , Deficiência de Vitamina D/fisiopatologia , Vitamina D/sangue , Vitaminas/sangue , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Testículo/metabolismo
6.
Environ Res ; 174: 176-187, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31036329

RESUMO

INTRODUCTION: The rapid rise in global concerns about the adverse health effects of exposure to radiofrequency radiation (RFR) generated by common devices such as mobile phones has prompted scientists to further investigate the biological effects of these environmental exposures. Non-targeted effects (NTEs) are responses which do not need a direct exposure to be expressed and are particularly significant at low energy radiations. Although NTEs of ionizing radiation are well documented, there are scarcely any studies on non-targeted responses such as bystander effect (BE) after exposure to non-ionizing radiation. The main goal of this research is to study possible RFR-induced BE. MATERIAL AND METHODS: Chinese hamster ovary cells were exposed to 900 MHz GSM RFR at an average specific absorption rate (SAR) of 2 W/kg for 4, 12 and 24 hours (h). To generate a uniformly distributed electromagnetic field and avoid extraneous RF exposures a cavity was desined and used. Cell membrane permeability, cell redox activity, metabolic and mitotic cell death and DNA damages were analyzed. Then the most effective exposure durations and statistically significant altered parameters were chosen to assess the induction of BE through medium transfer procedure. Furthermore, intra and extra cellular reactive oxygen species (ROS) levels were measured to assess the molecular mechanism of BE induced by non-ionizing radiation. RESULTS: No statistically significant alteration was found in cell membrane permeability, cell redox activity, metabolic cell activity and micronuclei (MN) frequency in the cells directly exposed to RFR for 4, 12, or 24 h. However, RFR exposure for 24 h caused a statistically significant decrease in clonogenic ability as well as a statistically significant increase in olive moment in both directly exposed and bystander cells which received media from RFR-exposed cells (conditioned culture medium; CCM). Exposure to RFR also statistically significant elevated both intra and extra cellular levels of ROS. CONCLUSION: Our observation clearly indicated the induction of BE in cells treated with CCM. To our knowledge, this is the first report that a non-ionizing radiation (900 MHz GSM RFR) can induce bystander effect. As reported for ionizing radiation, our results proposed that ROS can be a potential molecule in indirect effect of RFR. On the other hand, we found the importance of ROS in direct effect of RFR but in different ways.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Exposição à Radiação , Ondas de Rádio , Animais , Efeito Espectador , Células CHO , Cricetinae , Cricetulus
7.
Sensors (Basel) ; 19(5)2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30818868

RESUMO

A three-dimensional (3D) electromagnetic torso scanner system is presented. This system aims at providing a complimentary/auxiliary imaging modality to supplement conventional imaging devices, e.g., ultrasound, computerized tomography (CT) and magnetic resonance imaging (MRI), for pathologies in the chest and upper abdomen such as pulmonary abscess, fatty liver disease and renal cancer. The system is comprised of an array of 14 resonance-based reflector (RBR) antennas that operate from 0.83 to 1.9 GHz and are located on a movable flange. The system is able to scan different regions of the chest and upper abdomen by mechanically moving the antenna array to different positions along the long axis of the thorax with an accuracy of about 1 mm at each step. To verify the capability of the system, a three-dimensional imaging algorithm is proposed. This algorithm utilizes a fast frequency-based microwave imaging method in conjunction with a slice interpolation technique to generate three-dimensional images. To validate the system, pulmonary abscess was simulated within an artificial torso phantom. This was achieved by injecting an arbitrary amount of fluid (e.g., 30 mL of water), into the lungs regions of the torso phantom. The system could reliably and reproducibly determine the location and volume of the embedded target.

8.
J Biol Chem ; 292(4): 1178-1186, 2017 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-27941021

RESUMO

Phospholipases Cγ (PLCγ) 1 and 2 are a class of highly homologous enzymes modulating a variety of cellular pathways through production of inositol 1,4,5-trisphosphate and diacylglycerol (DAG). Our previous studies demonstrated the importance of PLCγ2 in osteoclast (OC) differentiation by modulating inositol 1,4,5-trisphosphate-mediated calcium oscillations and the up-regulation of the transcription factor NFATc1. Surprisingly, despite being expressed throughout osteoclastogenesis, PLCγ1 did not compensate for PLCγ2 deficiency. Because both isoforms are activated during osteoclastogenesis, it is plausible that PLCγ1 modulates OC development independently of PLCγ2. Here, we utilized PLCγ1-specific shRNAs to delete PLCγ1 in OC precursors derived from wild type (WT) mice. Differently from PLCγ2, we found that PLCγ1 shRNA significantly suppresses OC differentiation by limiting colony-stimulating factor 1 (CSF-1)-dependent proliferation and ß-catenin/cyclinD1 levels. Confirming the specificity toward CSF-1 signaling, PLCγ1 is recruited to the CSF-1 receptor following exposure to the cytokine. To understand how PLCγ1 controls cell proliferation, we turned to its downstream effector, DAG. By utilizing cells lacking the DAG kinase ζ, which have increased DAG levels, we demonstrate that DAG modulates CSF-1-dependent proliferation and ß-catenin/cyclinD1 levels in OC precursors. Most importantly, the proliferation and osteoclastogenesis defects observed in the absence of PLCγ1 are normalized in PLCγ1/DAG kinase ζ double null cells. Taken together, our study shows that PLCγ1 controls OC numbers via a CSF-1-dependent DAG/ß-catenin/cyclinD1 pathway.


Assuntos
Ciclina D1/metabolismo , Diglicerídeos/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Osteoclastos/metabolismo , Fosfolipase C gama/metabolismo , Transdução de Sinais/fisiologia , beta Catenina/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Ciclina D1/genética , Diacilglicerol Quinase/genética , Diacilglicerol Quinase/metabolismo , Diglicerídeos/genética , Técnicas de Silenciamento de Genes , Fator Estimulador de Colônias de Macrófagos/farmacologia , Camundongos , Osteoclastos/citologia , Fosfolipase C gama/genética , Transdução de Sinais/efeitos dos fármacos , beta Catenina/genética
9.
BMC Med Imaging ; 14: 32, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25223399

RESUMO

BACKGROUND: Two-dimensional projection radiographs have been traditionally considered the modality of choice for cephalometric analysis. To overcome the shortcomings of two-dimensional images, three-dimensional computed tomography (CT) has been used to evaluate craniofacial structures. However, manual landmark detection depends on medical expertise, and the process is time-consuming. The present study was designed to produce software capable of automated localization of craniofacial landmarks on cone beam (CB) CT images based on image registration and to evaluate its accuracy. METHODS: The software was designed using MATLAB programming language. The technique was a combination of feature-based (principal axes registration) and voxel similarity-based methods for image registration. A total of 8 CBCT images were selected as our reference images for creating a head atlas. Then, 20 CBCT images were randomly selected as the test images for evaluating the method. Three experts twice located 14 landmarks in all 28 CBCT images during two examinations set 6 weeks apart. The differences in the distances of coordinates of each landmark on each image between manual and automated detection methods were calculated and reported as mean errors. RESULTS: The combined intraclass correlation coefficient for intraobserver reliability was 0.89 and for interobserver reliability 0.87 (95% confidence interval, 0.82 to 0.93). The mean errors of all 14 landmarks were <4 mm. Additionally, 63.57% of landmarks had a mean error of <3 mm compared with manual detection (gold standard method). CONCLUSION: The accuracy of our approach for automated localization of craniofacial landmarks, which was based on combining feature-based and voxel similarity-based methods for image registration, was acceptable. Nevertheless we recommend repetition of this study using other techniques, such as intensity-based methods.


Assuntos
Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Crânio/diagnóstico por imagem , Adolescente , Adulto , Criança , Humanos , Imageamento Tridimensional/métodos , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Design de Software , Adulto Jovem
10.
Cancer Rep (Hoboken) ; 7(6): e2113, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39031907

RESUMO

BACKGROUND: Renal cell carcinoma (RCC) is one of the most common and prevalent cancers all around the world with a prevalence of 3%. Approximately twenty percent of patients present with metastasis at the time of diagnosis, while late metastasis in renal cell carcinoma is a quite familiar phenomenon. Head and neck and particularly thyroid metastasis from RCC are rare events. CASE: We present a case of a 75-year-old woman who developed thyroid nodules 13 years after nephrectomy for RCC. Diagnosis confirmed metastatic RCC through clinical history, histomorphology, and immunohistochemistry. Imaging studies revealed thyroid lesions without metastasis in other organs. The patient underwent total thyroidectomy and remains symptom-free after 2 years of follow-up. CONCLUSION: This case highlights the importance of considering metastatic lesions is crucial in managing thyroid nodules in patients with a history of cancer, particularly RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Nódulo da Glândula Tireoide , Tireoidectomia , Humanos , Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/cirurgia , Feminino , Idoso , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/diagnóstico , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/secundário , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/diagnóstico , Nefrectomia
11.
J Leukoc Biol ; 115(3): 511-524, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-37952106

RESUMO

Tissue infiltration by circulating leukocytes via directed migration (also referred to as chemotaxis) is a common pathogenic mechanism of inflammatory diseases. G protein-coupled receptors (GPCRs) are essential for sensing chemokine gradients and directing the movement of leukocytes during immune responses. The tumor necrosis factor α-induced protein 8-like (TIPE or TNFAIP8L) family of proteins are newly described pilot proteins that control directed migration of murine leukocytes. However, how leukocytes integrate site-specific directional cues, such as chemokine gradients, and utilize GPCR and TIPE proteins to make directional decisions are not well understood. Using both gene knockdown and biochemical methods, we demonstrated here that 2 human TIPE family members, TNFAIP8 and TIPE2, were essential for directed migration of human CD4+ T cells. T cells deficient in both of these proteins completely lost their directionality. TNFAIP8 interacted with the Gαi subunit of heterotrimeric (α, ß, γ) G proteins, whereas TIPE2 bound to PIP2 and PIP3 to spatiotemporally control immune cell migration. Using deletion and site-directed mutagenesis, we established that Gαi interacted with TNFAIP8 through its C-terminal amino acids, and that TIPE2 protein interacted with PIP2 and PIP3 through its positively charged amino acids on the α0 helix and at the grip-like entrance. We also discovered that TIPE protein membrane translocation (i.e. crucial for sensing chemokine gradients) was dependent on PIP2. Collectively, our work describes a new mechanistic paradigm for how human T cells integrate GPCR and phospholipid signaling pathways to control directed migration. These findings have implications for therapeutically targeting TIPE proteins in human inflammatory and autoimmune diseases.


Assuntos
Sistemas do Segundo Mensageiro , Transdução de Sinais , Humanos , Animais , Camundongos , Quimiocinas , Aminoácidos , Lipídeos , Peptídeos e Proteínas de Sinalização Intracelular
12.
Caspian J Intern Med ; 15(2): 307-312, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38807732

RESUMO

Background: There are few reports evaluating different factors, including the severity of duodenal histopathological findings and serological levels of celiac disease (CD), in increasing the probability of thyroid diseases (TD) in adults and children with CD, so, we designed this research. Methods: CD was defined as Marsh type 2 or higher in duodenal histopathology and serological levels of anti-transglutaminase antibodies (anti-tTG) equal to or greater than 18 IU/ml. To assess the likelihood of TD in CD patients, logistic regression analysis was employed. Results: 538 patients were included in this study. Of these, 354 (65.8%) were females and 184 (34.2%) were males. 370 (68.8%) patients were children. Overall, 57 (10.6%) patients had TD, of which 49 (9.1%) had hypothyroidism and 8 (1.5%) had hyperthyroidism. Adults had a significantly higher probability of developing TD than children (OR 1.9; 95% CI 1.1-3.4; P = 0.03). The odds of developing TD were also significantly higher in patients with family marriage in parents (OR 2.3; 95% CI 1.1-4.7; P = 0.03). Other variables such as gastrointestinal symptoms, anti-tTG levels, and severity of Marsh classification did not exhibit a substantial rise in the likelihood of TD development. Conclusion: The study findings indicated that the likelihood of developing TD in CD patients can be linked to advancing age and having family marriage in parents, while there was no significant association observed with anti-tTG levels, severity of histological damage, and gastrointestinal symptoms.

13.
Sci Rep ; 14(1): 5760, 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459073

RESUMO

Stroke is a leading cause of death and disability worldwide, and early diagnosis and prompt medical intervention are thus crucial. Frequent monitoring of stroke patients is also essential to assess treatment efficacy and detect complications earlier. While computed tomography (CT) and magnetic resonance imaging (MRI) are commonly used for stroke diagnosis, they cannot be easily used onsite, nor for frequent monitoring purposes. To meet those requirements, an electromagnetic imaging (EMI) device, which is portable, non-invasive, and non-ionizing, has been developed. It uses a headset with an antenna array that irradiates the head with a safe low-frequency EM field and captures scattered fields to map the brain using a complementary set of physics-based and data-driven algorithms, enabling quasi-real-time detection, two-dimensional localization, and classification of strokes. This study reports clinical findings from the first time the device was used on stroke patients. The clinical results on 50 patients indicate achieving an overall accuracy of 98% in classification and 80% in two-dimensional quadrant localization. With its lightweight design and potential for use by a single para-medical staff at the point of care, the device can be used in intensive care units, emergency departments, and by paramedics for onsite diagnosis.


Assuntos
Encéfalo , Acidente Vascular Cerebral , Humanos , Encéfalo/diagnóstico por imagem , Fenômenos Eletromagnéticos , Cabeça , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética
14.
J Biomed Phys Eng ; 14(2): 169-182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628888

RESUMO

Background: As the use of electronic devices such as mobile phones, tablets, and computers continues to rise globally, concerns have been raised about their potential impact on human health. Exposure to high energy visible (HEV) blue light, emitted from digital screens, particularly the so-called artificial light at night (ALAN), has been associated with adverse health effects, ranging from disruption of circadian rhythms to cancer. Breast cancer incidence rates are also increasing worldwide. Objective: This study aimed at finding a correlation between breast cancer and exposure to blue light from mobile phone. Material and Methods: In this retrospective matched case-control study, we aimed to investigate whether exposure to blue light from mobile phone screens is associated with an increased risk of female breast cancer. We interviewed 301 breast cancer patients (cases) and 294 controls using a standard questionnaire and performed multivariate analysis, chi-square, and Fisher's exact tests for data analysis. Results: Although heavy users in the case group of our study had a statistically significant higher mean 10-year cumulative exposure to digital screens compared to the control group (7089±14985 vs 4052±12515 hours, respectively, P=0.038), our study did not find a strong relationship between exposure to HEV and development of breast cancer. Conclusion: Our findings suggest that heavy exposure to HEV blue light emitted from mobile phone screens at night might constitute a risk factor for promoting the development of breast cancer, but further large-scale cohort studies are warranted.

15.
Membranes (Basel) ; 13(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37504998

RESUMO

The use of mixed matrix membranes (MMMs) to facilitate the production of biofuels has attracted significant research interest in the field of renewable energy. In this study, the pervaporation separation of butanol from aqueous solutions was studied using a series of MMMs, including zeolitic imidazolate frameworks (ZIF-8)-polydimethylsiloxane (PDMS) and zinc oxide-PDMS mixed matrix membranes. Although several studies have reported that mixed matrix membranes incorporating ZIF-8 nanoparticles showed improved pervaporation performances attributed to their intrinsic microporosity and high specific surface area, an in-depth study on the role of ZIF-8 nanoparticle size in MMMs has not yet been reported. In this study, different average sizes of ZIF-8 nanoparticles (30, 65, and 80 nm) were synthesized, and the effects of particle size and particle loading content on the performance of butanol separation using MMMs were investigated. Furthermore, zinc oxide nanoparticles, as non-porous fillers with the same metalcore as ZIF-8 but with a very different geometric shape, were used to illustrate the importance of the particle geometry on the membrane performance. Results showed that small-sized ZIF-8 nanoparticles have better permeability and selectivity than medium and large-size ZIF-8 MMMs. While the permeation flux increased continuously with an increase in the loading of nanoparticles, the selectivity reached a maximum for MMM with 8 wt% smaller-size ZIF-8 nanoparticle loading. The flux and butanol selectivity increased by 350% and 6%, respectively, in comparison to those of neat PDMS membranes prepared in this study.

16.
Med Phys ; 50(6): 3651-3660, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36779548

RESUMO

BACKGROUND: Arrays of thick segmented crystalline scintillators are useful x-ray converters for image-guided radiation therapy using electronic portal imaging (EPI) and megavoltage cone-beam computed tomography (MV-CBCT). Ionizing-radiation-only simulations previously showed relatively low modulation transfer function (MTF) in parallel-element arrays because of beam divergence. Hence, a focused-element geometry (matching the beam divergence) has been proposed. The "full" (ionizing and optical) MTF performance of such a focused geometry compared to its radiation-only MTF has, however, not been fully investigated. PURPOSE: To study the full MTF performance of such arrays in a more realistic situation in which optical characteristics are also included using an in-house detector model that supports light transport, and quantify the errors in MTF estimation when the optical stage is ignored. METHODS: First, radiation (x-ray and electron) transport was simulated. Then, transport of the generated optical photons was modeled using ScintSim2, an optical Monte Carlo (MC) code developed in MATLAB for simulation of two-dimensional (2D) parallel- and focused-element scintillator arrays. The full-MTF responses of focused- and parallel-element geometries, for a large array of 3 × 3 mm2 CsI:Tl detector elements of 10, 40, and 60 mm thicknesses, were examined. For each configuration, a composite line spread function (LSF) was calculated to obtain the MTF. RESULTS: At the Nyquist frequency, for 10 mm-thick central elements and 60 mm-thick peripheral parallel elements, full-MTF exhibited a drop of up to 15 and 79 times, respectively, compared with radiation-only MTF. This was found to be partly attributable to the angular distribution of the light emerging from the detector-element exit face and the dependence on its aspect ratio, since the light exiting thicker scintillators exhibited a more forward-directed distribution. Focused elements provided an increase of up to nine times in peripheral-area full MTF values. CONCLUSIONS: Full MTF was up to 79 times lower than radiation-only MTF. Focused arrays preserved full MTF by up to nine times compared to parallel elements. The differences in the results obtained with and without inclusion of optical photons emphasize the need to include light transport when optimizing thick segmented scintillation detectors. Besides their application in detector optimization for radiotherapy megavoltage photon imaging, these findings can also be useful for other segmented-scintillator-based imaging systems, for example, in nuclear medicine, or in 2D detection systems for quality assurance of MR-linacs.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Radioterapia Guiada por Imagem , Radiografia , Simulação por Computador , Fótons , Tálio , Método de Monte Carlo
17.
Adv Biomed Res ; 12: 31, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37057248

RESUMO

Background: Health-care workers (HCWs) are in the frontline for fighting the coronavirus disease 2019 (COVID-19) pandemic and are at higher risk of acquiring the infection. Therefore, the defining immunity status among HCWs helps mitigate the exposure risk. In this study, we investigated the anti-SARS-CoV-2 immunoglobulin G (IgG) and immunoglobulin M (IgM) and also the associated risk factors in the HCWs working in Isfahan University of Medical Sciences COVID-19 referral hospitals. Materials and Methods: In a cross-sectional study, demographics, COVID-19 symptoms during the past 2 weeks, and health-care details were collected from 200 consenting health workers of COVID-center-hospitals of Isfahan University of Medical Sciences from 23 October to 21 December 2020. The recombinant SARS-CoV2 nucleocapsid protein enzyme-linked immunosorbent assay-based IgM, and IgG antibody tests were evaluated. Data were analyzed using Chi-square and independent-t-student tests, and P < 0.05 was considered significant. Results: One hundred and forty-one women and 59 men with a mean age of 36.4 ± 7.77 years participated in the study. IgG Ab and IgM Ab were positive in 77 (38.5%) and 12 (6%) of samples, respectively, and both antibodies were detected in 9 (4.5%). Higher ages, direct contact with the patients with COVID-19, muscle pain, loss of taste and smell, fever, and cough were the factors associated with antibody seropositivity against SARS-CoV2. Conclusion: This study demonstrated that the prevalence of HCWs with antibodies against SARS-CoV-2 is relatively high in Isfahan University referral hospitals. The development of safety protocols and screening and vaccination strategies in the frontline HCWs must be implemented to reduce the burden of infection.

18.
Cutan Ocul Toxicol ; 31(2): 95-103, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21988705

RESUMO

BACKGROUND: Chronic pruritic skin lesions are among the common late complications of sulfur mustard intoxication. In the present randomized double-blind clinical trial, therapeutic efficacy of Aloe vera/olive oil combination cream in the alleviation of these lesions was evaluated and compared to that of betamethasone 0.1% cream. METHODS: Sixty-seven Iranian chemical warfare-injured veterans were randomized to apply A. vera/olive oil (n=34, completers=31) or betamethasone 0.1% (n=33, completers=32) cream twice daily for 6 weeks. Evaluation of pruritus severity was performed using a pruritic score questionnaire and visual analogue scale (VAS). RESULTS: Both treatments were associated with significant reductions in the frequency of pruritus (p<0.05), burning sensation (p<0.01 and p<0.001 in A. vera/olive oil and betamethasone group, respectively), scaling (p<0.01 and p<0.05) and dry skin (p<0.001) at the end of trial. Fissure and excoriation were only reduced in the A. vera group (p<0.05). The change in the frequency of hyper- and hypopigmentation lesions, blisters, erythema and lichenification did not reach statistical significance in any of the groups (p>0.05). Mean pruritus (p<0.05) and VAS scores (p<0.01 and p<0.05) were significantly decreased by the end of trial in both groups. The rate of improvement in the pruritus severity [defined as being classified in a less severe category (mild, moderate and severe)] was found to be comparable between the groups (p>0.05). CONCLUSION: A. vera/olive oil cream was at least as effective as betamethasone 0.1% in the treatment of sulfur mustard-induced chronic skin complications and might serve as a promising therapeutic option for the alleviation of symptoms in mustard gas-exposed patients.


Assuntos
Aloe , Betametasona/uso terapêutico , Glucocorticoides/uso terapêutico , Gás de Mostarda/toxicidade , Óleos de Plantas/uso terapêutico , Dermatopatias/tratamento farmacológico , Adulto , Anti-Inflamatórios/uso terapêutico , Substâncias para a Guerra Química/toxicidade , Método Duplo-Cego , Emolientes/uso terapêutico , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Azeite de Oliva , Prurido/induzido quimicamente , Prurido/tratamento farmacológico , Dermatopatias/induzido quimicamente , Resultado do Tratamento , Veteranos
19.
Dent Res J (Isfahan) ; 19: 41, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35915711

RESUMO

Background: This study aimed to assess the relationship between the osteoporotic condition and periodontitis in postmenopausal women. Materials and Methods: Ninety-four women aged 50-80 years were studied in this cross-sectional study. Bone mineral density (BMD) of lumbar vertebra BMD (LBMD), total hip BMD (HBMD), and neck of femur BMD (NBMD) was assessed using standardized dual-energy X-ray absorptiometry (DXA) (normal: T-score ≥-1, osteopenic: -2.5 ≤ t-score <-1, osteoporotic: T-score <-2.5). Bleeding point index (BI), O'Leary plaque index (PI), and clinical attachment loss (CAL) were recorded. Cementoenamel junction, alveolar-crest distance (CEJ-AC) was measured from cone-beam computed tomography images. Periodontitis severity was represented by CAL and CEJ-AC distance. One-way analysis of variance followed by Post hoc Tukey was performed for examining differences among the groups for different variables. Pearson correlation coefficient® and backward regression analysis were used to investigate the effect of confounding variables on CEJ-AC as the dependent variable. Significance was considered at P < 0.05. Results: Mean CEJ-AC was significantly higher in the osteoporotic and osteopenic groups compared to the normal group (P = 0.001). There was a significant positive correlation between CEJ-AC and NBMD and LBMD (P < 0.001). The associations between LBMD and CEJ-AC existed even after adjusting for confounding factors (P = 0.002). The differences in BI, PI, and CAL were not statistically different between the groups (P > 0.05). Conclusion: Although osteoporosis is not the main cause of periodontitis, it can indirectly affect periodontal status by increasing CEJ-AC. Early diagnosis of osteoporosis followed by early referral to a dentist for the treatment of potential existing periodontal diseases is important to avoid complications among postmenopausal women.

20.
J Biomed Phys Eng ; 12(6): 637-644, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36569561

RESUMO

Background: Nowadays, there is a growing global concern over rapidly increasing screen time (smartphones, tablets, and computers). An accumulating body of evidence indicates that prolonged exposure to short-wavelength visible light (blue component) emitted from digital screens may cause cancer. The application of machine learning (ML) methods has significantly improved the accuracy of predictions in fields such as cancer susceptibility, recurrence, and survival. Objective: To develop an ML model for predicting the risk of breast cancer in women via several parameters related to exposure to ionizing and non-ionizing radiation. Material and Methods: In this analytical study, three ML models Random Forest (RF), Support Vector Machine (SVM), and Multi-Layer Perceptron Neural Network (MLPNN) were used to analyze data collected from 603 cases, including 309 breast cancer cases and 294 gender and age-matched controls. Standard face-to-face interviews were performed using a standard questionnaire for data collection. Results: The examined models RF, SVM, and MLPNN performed well for correctly classifying cases with breast cancer and the healthy ones (mean sensitivity> 97.2%, mean specificity >96.4%, and average accuracy >97.1%). Conclusion: Machine learning models can be used to effectively predict the risk of breast cancer via the history of exposure to ionizing and non-ionizing radiation (including blue light and screen time issues) parameters. The performance of the developed methods is encouraging; nevertheless, further investigation is required to confirm that machine learning techniques can diagnose breast cancer with relatively high accuracies automatically.

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