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1.
Cureus ; 16(6): e61483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38952601

RESUMO

This research study explores of the effectiveness of a machine learning image classification model in the accurate identification of various types of brain tumors. The types of tumors under consideration in this study are gliomas, meningiomas, and pituitary tumors. These are some of the most common types of brain tumors and pose significant challenges in terms of accurate diagnosis and treatment. The machine learning model that is the focus of this study is built on the Google Teachable Machine platform (Alphabet Inc., Mountain View, CA). The Google Teachable Machine is a machine learning image classification platform that is built from Tensorflow, a popular open-source platform for machine learning. The Google Teachable Machine model was specifically evaluated for its ability to differentiate between normal brains and the aforementioned types of tumors in MRI images. MRI images are a common tool in the diagnosis of brain tumors, but the challenge lies in the accurate classification of the tumors. This is where the machine learning model comes into play. The model is trained to recognize patterns in the MRI images that correspond to the different types of tumors. The performance of the machine learning model was assessed using several metrics. These include precision, recall, and F1 score. These metrics were generated from a confusion matrix analysis and performance graphs. A confusion matrix is a table that is often used to describe the performance of a classification model. Precision is a measure of the model's ability to correctly identify positive instances among all instances it identified as positive. Recall, on the other hand, measures the model's ability to correctly identify positive instances among all actual positive instances. The F1 score is a measure that combines precision and recall providing a single metric for model performance. The results of the study were promising. The Google Teachable Machine model demonstrated high performance, with accuracy, precision, recall, and F1 scores ranging between 0.84 and 1.00. This suggests that the model is highly effective in accurately classifying the different types of brain tumors. This study provides insights into the potential of machine learning models in the accurate classification of brain tumors. The findings of this study lay the groundwork for further research in this area and have implications for the diagnosis and treatment of brain tumors. The study also highlights the potential of machine learning in enhancing the field of medical imaging and diagnosis. With the increasing complexity and volume of medical data, machine learning models like the one evaluated in this study could play a crucial role in improving the accuracy and efficiency of diagnoses. Furthermore, the study underscores the importance of continued research and development in this field to further refine these models and overcome any potential limitations or challenges. Overall, the study contributes to the field of medical imaging and machine learning and sets the stage for future research and advancements in this area.

2.
Technol Health Care ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38820040

RESUMO

BACKGROUND: Cardiovascular diseases remain a leading cause of global morbidity and mortality, with heart attacks and strokes representing significant health challenges. The accurate, early diagnosis and management of these conditions are paramount in improving patient outcomes. The specific disease, cardiovascular occlusions, has been chosen for the study due to the significant impact it has on public health. Cardiovascular diseases are a leading cause of mortality globally, and occlusions, which are blockages in the blood vessels, are a critical factor contributing to these conditions. OBJECTIVE: By focusing on cardiovascular occlusions, the study aims to leverage machine learning to improve the prediction and management of these events, potentially helping to reduce the incidence of heart attacks, strokes, and other related health issues. The use of machine learning in this context offers the promise of developing more accurate and timely interventions, thus improving patient outcomes. METHODS: We analyze diverse datasets to assess the efficacy of various machine learning algorithms in predicting heart attacks and strokes, comparing their performance to pinpoint the most accurate and reliable models. Additionally, we classify individuals by their predicted risk levels and examine key features that correlate with the incidence of cardiovascular events. The PyCaret machine learning library's Classification Module was key in developing predictive models which were evaluated with stratified cross-validation for reliable performance estimates. RESULTS: Our findings suggest that machine learning can significantly improve the prediction accuracy for heart attacks and strokes, facilitating earlier and more precise interventions. We also discuss the integration of machine learning models into clinical practice, addressing potential challenges and the need for healthcare professionals to interpret and apply these predictions effectively. CONCLUSIONS: The use of machine learning for risk stratification and the identification of modifiable factors may empower preemptive approaches to cardiovascular care, ultimately aiming to reduce the occurrence of life-threatening events and improve long-term patient health trajectories.

3.
Brain Sci ; 14(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38671975

RESUMO

Epilepsy is one of the most common neurological disorders globally, affecting about 50 million people, with nearly 80% of those affected residing in low- and middle-income countries. It is characterized by recurrent seizures that result from abnormal electrical brain activity, with seizures varying widely in manifestation. The exploration of the biomechanical effects that seizures have on brain dynamics and stress levels is relevant for the development of more effective treatments and protective strategies. This study uses a blend of experimental data and computational simulations to assess the brain's physical response during seizures, particularly focusing on the behavior of cerebrospinal fluid and the resulting mechanical stresses on different brain regions. Notable findings show increases in stress, predominantly in the posterior gyri and brainstem, during seizures and an evidence of brain displacement relative to the skull. These observations suggest a dynamic and complex interaction between the brain and skull, with maximum shear stress regions demonstrating the limited yet essential protective role of the CSF. By providing a deeper understanding of the mechanical changes occurring during seizures, this research supports the goal of advancing diagnostic tools, informing more targeted treatment interventions, and guiding the creation of customized therapeutic strategies to enhance neurological care and protect against the adverse effects of seizures.

4.
Cureus ; 15(10): e46962, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38022246

RESUMO

Background It is estimated that around 450,000 traumatic brain injury cases have occurred in the 21st century with possible under-reporting. Computational simulations are increasingly used to study the pathophysiology of traumatic brain injuries among US military personnel. This approach allows for investigation without ethical concerns surrounding live subject testing. Methodology The pertinent data on head acceleration is applied to a detailed 3D model of a patient-specific head, which encompasses all significant components of the brain and its surrounding fluid. The use of finite element analysis and smoothed-particle hydrodynamics serves to replicate the interaction between these elements during discharge through simulation of their fluid-structure dynamics. Results The stress levels of the brain are assessed at varying time intervals subsequent to the explosion. The regions where there is an intersection between the skull and brain are observed, along with the predominant orientations in which displacement of the brain occurs resulting in a brain injury. Conclusions It has been determined that the cerebrospinal fluid is inadequate in preventing brain damage caused by multiple abrupt directional shifts of the head. Accordingly, additional research must be undertaken to enhance our comprehension of the injury mechanisms linked with consecutive changes in acceleration impacting the head.

5.
Catheter Cardiovasc Interv ; 102(5): 919-928, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37698294

RESUMO

BACKGROUND: High-grade or complete atrioventricular block (AVB) requiring permanent pacemaker (PPM) implantation is a known complication of transcatheter aortic valve replacement (TAVR). Wenckebach AVB induced by rapid atrial pacing (RAP) after TAVR was previously demonstrated in an observational analysis to be an independent predictor for PPM. We sought to investigate the utility of both pre- and post-TAVR RAP in predicting PPM implantation. METHODS: In a single-center, prospective study, 421 patients underwent TAVR with balloon-expandable valves (BEV) between April 2020 and August 2021. Intraprocedural RAP was performed in patients without a pre-existing pacemaker, atrial fibrillation/flutter, or intraprocedural complete AVB to assess for RAP-induced Wenckebach AVB. The primary outcome was PPM within 30 days after TAVR. RESULTS: RAP was performed in 253 patients, of whom 91.3% underwent post-TAVR RAP and 61.2% underwent pre-TAVR RAP. The overall PPM implantation rate at 30 days was 9.9%. Although there was a numerically higher rate of PPM at 30 days in patients with RAP-induced Wenckebach AVB, it did not reach statistical significance (13.3% vs. 8.4%, p = 0.23). In a multivariable analysis, RAP-induced Wenckebach was not an independent predictor for PPM implantation at 30 days after TAVR. PPM rates at 30 days were comparable in patients with or without pre-TAVR pacing-induced Wenckebach AVB (11.8% vs. 8.2%, p = 0.51) and post-TAVR pacing-induced Wenckebach AVB (10.2% vs. 5.8%, p = 0.25). CONCLUSION: In patients who underwent TAVR with BEV, there were no statistically significant differences in PPM implantation rates at 30 days regardless of the presence or absence of RAP-induced Wenckebach AVB. Due to conflicting results between the present study and the prior observational analysis, future studies with larger sample sizes are warranted to determine the role of RAP during TAVR as a risk-stratification tool for significant AVB requiring PPM after TAVR.


Assuntos
Estenose da Valva Aórtica , Fibrilação Atrial , Bloqueio Atrioventricular , Próteses Valvulares Cardíacas , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/etiologia , Fibrilação Atrial/terapia , Estudos Prospectivos , Próteses Valvulares Cardíacas/efeitos adversos , Estimulação Cardíaca Artificial/efeitos adversos , Resultado do Tratamento , Fatores de Risco , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/terapia , Marca-Passo Artificial/efeitos adversos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia
6.
Biology (Basel) ; 12(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37508455

RESUMO

Using fluid-structure interaction algorithms to simulate the human circulatory system is an innovative approach that can provide valuable insights into cardiovascular dynamics. Fluid-structure interaction algorithms enable us to couple simulations of blood flow and mechanical responses of the blood vessels while taking into account interactions between fluid dynamics and structural behaviors of vessel walls, heart walls, or valves. In the context of the human circulatory system, these algorithms offer a more comprehensive representation by considering the complex interplay between blood flow and the elasticity of blood vessels. Algorithms that simulate fluid flow dynamics and the resulting forces exerted on vessel walls can capture phenomena such as wall deformation, arterial compliance, and the propagation of pressure waves throughout the cardiovascular system. These models enhance the understanding of vasculature properties in human anatomy. The utilization of fluid-structure interaction methods in combination with medical imaging can generate patient-specific models for individual patients to facilitate the process of devising treatment plans. This review evaluates current applications and implications of fluid-structure interaction algorithms with respect to the vasculature, while considering their potential role as a guidance tool for intervention procedures.

7.
Cureus ; 15(6): e40839, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37492830

RESUMO

Situs inversus totalis (SIT) is a rare condition characterized by mirror-image reversal of the thoracoabdominal organs. Although appendiceal pain is typically located in the right lower quadrant, in SIT, this can occur in the left lower quadrant. We present a case of a 40-year-old male with no medical history who complained of acute left lower quadrant pain, nausea, and vomiting with no other symptoms. A computed tomography scan revealed SIT and left-sided acute appendicitis (LSAA), which was managed surgically. This case highlights the importance of including appendicitis in the differential diagnosis for left lower quadrant pain.

8.
Cureus ; 15(4): e38185, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37252545

RESUMO

This report discusses the case of a patient with a past medical history of Poland syndrome and dextrocardia who was admitted for a transient ischemic attack. Poland syndrome is a rare genetic condition characterized by underdevelopment of chest wall musculature that presents with a variety of associations that may or may not be present in each case. This case report intends to discuss a unique presentation of Poland syndrome with dextrocardia, one of the rare conditions associated with Poland syndrome, as well as the treatment of Poland syndrome as a whole and possible associated complications.

9.
Eur Arch Otorhinolaryngol ; 280(7): 3475-3477, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37099144

RESUMO

PURPOSE: This case report describes the MRI appearance and significance of the myloglossus muscle, a variant extrinsic tongue muscle. METHODS: The myloglossus muscle was incidentally discovered on imaging performed for head and neck cancer evaluation. RESULTS: The myloglossus is best visualized on non-fat saturated T2 MRI and has signal characteristics that match those of muscle. It originates at the angle of the mandible and inserts into the tongue between the styloglossus and hyoglossus. CONCLUSION: Accurate identification and delineation of the extrinsic muscles of the tongue, including the myloglossus, is essential for proper staging and treatment of head and neck cancers. This case report attempts to fill a void in depicting the MRI appearance of myloglossus muscle.


Assuntos
Neoplasias da Língua , Língua , Humanos , Língua/diagnóstico por imagem , Músculos Faciais , Imageamento por Ressonância Magnética/métodos , Mandíbula
10.
Materials (Basel) ; 15(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35591450

RESUMO

Orthostatic hypotension is defined as a sudden drop in blood pressure upon standing from a sitting or supine position. The prevalence of this condition increases exponentially with age. Nonpharmacological treatments are always the first step in the management of this condition, such as the use of an abdominal constriction belt to optimize the blood volume in the abdomen. A multitude of clinical trials have shown the efficacy of elastic abdominal compression as well as compression using an inflatable bladder; however, there are currently few accessible consumer products that can provide abdominal compression by using an inflatable bladder that ensures the correct amount of pressure is being exerted on the subject. This study serves to quantitatively analyze forces exerted in inflatable abdominal binders, a novel treatment that fits the criterion for a first-line intervention for orthostatic hypotension. Quantitative values aim to indicate both the anatomic regions of the body subjected to the highest pressure by abdominal binding. Quantitative values will also create a model that can correlate the amount of compression on the subject with varying levels of pressure in the inflatable bladder. Inflatable binders of varying levels of inflation are used and localized pressure values are recorded at 5 different vertical points along the abdomen in the midsternal line and midclavicular line, at the locations of the splanchnic veins. These findings indicate both the differences in the compressive force applied through elastic and inflatable binding, as well the regions on the abdomen subject to the highest force load during compression by an abdominal binder. A medical manikin called the iStan Manikin was used to collect data. The pressure values on a manikin were sensed by the JUZO pressure monitor, a special device created for the purpose of measuring the force under compressive garments. The pressure inside the inflatable bladder was extrapolated from a pressure gauge and the pressure was recorded at different degrees of inflation of the belt (mmHG) along two different areas of the abdomen, the midsternal line and the midclavicular line, to discern differences in force exerted on the patient (mmHG). Computational studies on the data from the JUZO pressure monitor as well as the data from the pressure gauge on the inflatable bladder allow us to create a model that can correlate the amount of pressure in the inflatable bladder to the amount of pressure exerted on the belt, thus making sure that the patient is not being harmed by the compressive force. The results of our study indicate that there is no significant difference between the pressures exerted on the midsternal and midclavicular lines of the body by the abdominal binder and that no significant difference exists between the external pressure measured by the inflatable belt and the pressure sensed on the human body by the JUZO sensor; however, we were able to extrapolate an equation that can tell the user the amount of pressure that is actually being exerted on them based on the pressure in the inflatable bladder as recorded by the gauge.

11.
Headache ; 62(1): 36-56, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35041218

RESUMO

OBJECTIVE: The objective of this study was to understand current practice, clinician understanding, attitudes, barriers, and facilitators to optimal headache neuroimaging practices. BACKGROUND: Headaches are common in adults, and neuroimaging for these patients is common, costly, and increasing. Although guidelines recommend against routine headache neuroimaging in low-risk scenarios, guideline-discordant neuroimaging is still frequently performed. METHODS: We administered a 60-item survey to headache clinicians at the Veterans Affairs health system to assess clinician understanding and attitudes on headache neuroimaging and to determine neuroimaging practice patterns for three scenarios describing hypothetical patients with headaches. Descriptive statistics were used to summarize responses, stratified by clinician type (physicians or advanced practice clinicians [APCs]) and specialty (neurology or primary care). RESULTS: The survey was successfully completed by 431 of 1426 clinicians (30.2% response rate). Overall, 317 of 429 (73.9%) believed neuroimaging was overused for patients with headaches. However, clinicians would utilize neuroimaging a mean (SD) 30.9% (31.7) of the time in a low-risk scenario without red flags, and a mean 67.1% (31.9) of the time in the presence of minor red flags. Clinicians had stronger beliefs in the potential benefits (268/429, 62.5%) of neuroimaging compared to harms (181/429, 42.2%) and more clinicians were bothered by harms stemming from the omission of neuroimaging (377/426, 88.5%) compared to commission (329/424, 77.6%). Additionally, APCs utilized neuroimaging more frequently than physicians and were more receptive to potential interventions to improve neuroimaging utilization. CONCLUSIONS: Although a majority of clinicians believed neuroimaging was overused for patients with headaches, many would utilize neuroimaging in low-risk scenarios with a small probability of changing management. Future studies are needed to define the role of currently used red flags given their importance in neuroimaging decisions. Importantly, APCs may be an ideal target for future optimization efforts.


Assuntos
Atitude do Pessoal de Saúde , Utilização de Instalações e Serviços , Transtornos da Cefaleia/diagnóstico por imagem , Cefaleia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neuroimagem , Pesquisas sobre Atenção à Saúde , Humanos , Profissionais de Enfermagem , Assistentes Médicos , Médicos , Estados Unidos , United States Department of Veterans Affairs
12.
Antioxidants (Basel) ; 10(7)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201737

RESUMO

Cosmetics, commonly known as 'makeup' are products that can enhance the appearance of the human body. Cosmetic products include hair dyes, shampoos, skincare, sunscreens, kajal, and other makeup products. Cosmetics are generally applied throughout the face and over the neck region. Sunlight has different wavelengths of light, which include UV-A, UV-B, UV-C, and other radiations. Most cosmetic products have absorption maxima (λmax) in the range of visible light and UV-R. The effect of light-induced photosensitization of cosmetic products, which results in the production of free radicals through type-I and type-II photosensitization mechanisms. Free-radicals-mediated DNA damage and oxidative stress are common consequences of cosmetic phototoxicity. Cosmetic phototoxicity may include percutaneous absorption, skin irritation, eye irritation, photosensitization, mutagenicity, and genotoxicity. Oxidative stress induces membrane lipid peroxidation, glycoxidation, and protein covalent modifications, resulting in their dysfunction. Natural antioxidants inhibit oxidative-stress-induced cosmetic toxicity. Sunlight-induced photodegradation and accumulation of cosmetic photoproducts are also a matter of serious concern. India has tropical weather conditions throughout the year and generally, a majority of human activities such as commerce, agriculture, sports, etc. are performed under bright sunlight conditions. Thus, more focused and dedicated research is warranted to explore the effects of cosmetics on oxidative stress, glycoxidation of biomolecules, and photoproducts accumulation for its total human safety.

14.
J Neuroimaging ; 31(5): 1035-1043, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34002429

RESUMO

BACKGROUND AND PURPOSE: The prediction of radiotherapy outcome in head and neck paragangliomas is clinically important. We investigated perfusion and diffusion markers for evaluation of response to radiotherapy of head and neck paragangliomas. METHODS: We retrospectively reviewed 330 consecutive patients from January 2016 to September 2019 with suspected head and neck paragangliomas, and enrolled 11 patients (2 males, 9 females; age: 55.2 ± 10.3 years) who had conventional MRI and dynamic contrast-enhanced (DCE)-MRI before and after radiation therapy. Radiation therapy, consisting of external beam radiotherapy or stereotactic radiotherapy, was conducted at the radiation oncology department in a single center. Mean apparent diffusion coefficient (ADC), normalized mean ADC, and parameters of DCE-MRI were compared between pre- and post-treatment status by paired t-test. The Pearson correlation coefficient was used for the relationship between tumor volume ratio (post-treatment status/pre-treatment status) and pre-treatment and post-treatment values. RESULTS: Mean and normalized ADC values were statistically higher in post-treatment status than pre-treatment status (p = 0.005, p = 0.005, respectively), and Ktrans (volume transfer constant between extravascular, extracellular space [EES], and blood plasma per minute) and Kep (rate transfer constant between EES and blood plasma per minute) were significantly lower in post-treatment status than pre-treatment status (p = 0.007, p = 0.027, respectively). The correlation coefficient of the relationship between tumor volume ratio and pre-treatment Ktrans (r = 0.70; p = 0.016) and between tumor volume ratio and post-treatment Ktrans and Kep (r = 0.83; p = 0.002, r = 0.8; p = 0.003, respectively) was statistically significant. CONCLUSIONS: Ktrans has predictive potential to predict the response to radiation therapy of head and neck paragangliomas.


Assuntos
Meios de Contraste , Paraganglioma , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paraganglioma/diagnóstico por imagem , Paraganglioma/radioterapia , Estudos Retrospectivos
15.
Sci Total Environ ; 739: 140215, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758960

RESUMO

Rice production systems are the largest anthropogenic wetlands on earth and feed more than half of the world's population. However, they are also a major source of global anthropogenic greenhouse gas (GHG) emissions. Several agronomic strategies have been proposed to improve water-use efficiency and reduce GHG emissions. The aim of this study was to evaluate the impact of water-saving irrigation (alternate wetting and drying (AWD) vs. soil water potential (SWP)), contrasting land establishment (puddling vs. reduced tillage) and fertiliser application methods (broadcast vs. liquid fertilisation) on water-use efficiency, GHG emissions and rice yield. The experiment was laid out in a randomised complete block design with eight treatments (all combinations of the three factors) and four replicates. AWD combined with broadcasting fertilisation was superior to SWP in terms of maintaining yield. However, seasonal nitrous oxide (N2O) emissions were significantly reduced by 64% and 66% in the Broadcast-SWP and Liquid fertiliser-SWP treatments, respectively, compared to corresponding treatments in AWD. The SWP also significantly reduced seasonal methane (CH4) emissions by 34 and 30% in the broadcast and liquid fertilisation treatments, respectively. Area-scaled GWPs were reduced by 48% and 54% in Broadcast-SWP and Liquid fertiliser-SWP treatments respectively compared to the corresponding treatments in AWD. Compared to AWD, the broadcast and liquid fertilisation in SWP irrigation treatments reduced yield-scaled GWPs by 46% and 37%, respectively. In terms of suitability, based on yield-scaled GWPs, the treatments can be ordered as follows: Broadcast-SWP < Broadcast-AWD = Liquid fertiliser-SWP < Liquid fertiliser-AWD. Growing-season water use was 15% lower in the SWP treatments compared with the water-saving AWD. Reduced tillage reduced additional water use during land preparation. The conclusions of this study are that improved water management and timely coordination of N fertiliser with crop demand can reduce water use, N loss via N2O emissions, and CH4 emissions.

16.
J Ayub Med Coll Abbottabad ; 32(1): 152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468778

RESUMO

Eleven months old female patient presented to paediatric out patient with parents concerned about her facial swelling. Upon examination child's weight and height for age were normal on her percentiles, she had a cushingoid facies with plethoric cheeks (Figure-1,2) though generalized oedema was absent and there was centripetal obesity with some muscle wasting (Figure-3,4). Systemic examination was normal excluding blood pressure which was high for her age. Electrolytes and cortisol levels were normal. On further inquiry it was revealed that she had been using a nappy rash cream containing a potent steroid, i.e., fluticasone for 2 months and this was identified as a cause for her cushingoid features.


Assuntos
Síndrome de Cushing/induzido quimicamente , Hipertensão/induzido quimicamente , Creme para a Pele/efeitos adversos , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Dermatite das Fraldas/tratamento farmacológico , Feminino , Fluticasona/efeitos adversos , Fluticasona/uso terapêutico , Humanos , Doença Iatrogênica , Lactente , Pomadas/efeitos adversos , Pomadas/química , Pomadas/uso terapêutico , Creme para a Pele/química , Creme para a Pele/uso terapêutico
17.
J Cell Biochem ; 121(2): 1273-1282, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31709634

RESUMO

Prolonged exposure of the earth's surface to the sun's ultraviolet radiation may result in various skin diseases and cataract. Carbazole (CBZ), as a polycyclic-aromatic hydrocarbon (PAH), is blended with a five-member nitrogen-containing ring. It is found in cigarette smoke, coal, eye kohl, tattoo ink, and wood combustion and affects various types of flora and fauna. Our findings suggest that CBZ generates reactive oxygen species (ROS) like O2•- through type-I photodynamic reaction and causes phototoxicity in the human keratinocyte cell line (HaCaT), which has been proved by mitochondrial dehydrogenase and neutral red uptake assays. CBZ induces single strand DNA damage. We have investigated the involvement of the apoptotic pattern of cell death and confirmed it by cytochrome C release from mitochondria and caspase-9 activation. Similarly, photo-micronuclei formation was associated to CBZ-induced phototoxicity. The results of this study strongly support that the upregulation of bax, cyto-C, apaf-1, casp-9 and down regulation of bcl2, keap-1, nrf-2, and hmox-1 genes cause apoptopic cell death. Downregulation of antioxidant genes showed a significant amount of ROS generation by photosensitized CBZ. Therefore, the current study will be a step forward to safeguard human beings from sunlight-induced photosensitive CBZ prolonged exposure.


Assuntos
Carbazóis/farmacologia , Regulação da Expressão Gênica , Queratinócitos/patologia , Mitocôndrias/patologia , Estresse Oxidativo/efeitos dos fármacos , Pele/patologia , Raios Ultravioleta , Apoptose , Células Cultivadas , Citocromos c/metabolismo , Dano ao DNA , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio , Pele/efeitos dos fármacos , Pele/efeitos da radiação
18.
Toxicol Ind Health ; 35(7): 457-465, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31364504

RESUMO

Solar ultraviolet (UV) radiation is the main factor of photocarcinogenesis, photoaging, and photosensitivity; thus protection from biological damaging UV radiation is a concern. Sunscreens containing UV filters are the most preferred means of photoprotection but the safety and efficacy of UV filters are in question. Benzophenone (BP) and its derivatives, namely, benzophenone 1 (BP1), is commonly used in sunscreens as a UV blocker. The aim of this study was to assess the effects of BP and BP1 on the differential expression of proteins in human keratinocytes (HaCaT cells) under exposure to ultraviolet A radiation. Photosensitive proteins were screened from HaCaT cells by two-dimensional (2-D) gel electrophoresis, and identification of these differentially expressed proteins was performed by matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF)/TOF mass spectrometry. Protein identification was performed using the search program MASCOT and a database made of SUMO and GhJMJ12 amino acid sequences. Our results showed that the proteins involved directly or indirectly in apoptosis are 70 kDa heat shock protein, long-chain specific acyl-CoA dehydrogenase, serine/threonine-protein kinase, and FAM78A protein, which were upregulated in comparison to control HaCaT cells. The expressions of binding immunoglobulin protein, podocalyxin-like protein, actin, cytoplasmic, and calreticulin precursors were downregulated. The altered protein expression indicated that cell growth arrest and apoptosis were potential mechanisms of cytotoxicity and genotoxicity of BPs. The results of 2-D gel electrophoresis followed by mass spectrometry showed expression of novel proteins involved in promoting or initiating apoptotic pathways. Hence, we conclude that BPs should be avoided as a UV blocker from sunscreens because of its potential to promote apoptotic proteins in human skin keratinocytes.


Assuntos
Benzofenonas/farmacologia , Queratinócitos/efeitos dos fármacos , Protetores Solares/farmacologia , Raios Ultravioleta , Apoptose/efeitos dos fármacos , Biomarcadores , Eletroforese em Gel Bidimensional , Proteínas de Choque Térmico/efeitos dos fármacos , Humanos , Queratinócitos/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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