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1.
Environ Sci Technol ; 56(5): 2959-2967, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35148085

RESUMO

22 alkylated polycyclic aromatic hydrocarbons (alk-PAHs) were characterized in ambient air individually for the first time in urban and semi-urban locations in Toronto, Canada. Five unsubstituted PAHs were included for comparison. Results from the measurements were used to estimate benzo[a]pyrene equivalent toxicity (BaPeq) of individual compounds in order to investigate the significance of a single compound in contributing to the overall toxic equivalency (TEQ) of air mixtures. To determine which compounds merit further investigation, BaPeq values of individual compounds were compared to the measured BaP toxicity. Our results showed that both unsubstituted and alkylated PAHs were more abundant in the urban area (38 and 30%, respectively). Benzo[a]pyrene levels at the urban location exceeded Ontario's 24 h guideline (40% of the events), and on average, it was 5 times higher than that at the semi-urban area. Gas-phase two- and three-ring compounds contributed up to 39% (urban) and 76% (semi-urban) of the TEQ of all compounds analyzed. Some alk-PAHs such as 7,12-dimethylbenzo[a]anthracene had a huge impact on the toxicity of urban air, and its BaPeq was on average 8 times higher than that of BaP. We emphasize that the toxic impact of alkylated and gaseous PAHs, which is not routinely included in many air monitoring programs, is significant and should not be neglected.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Benzo(a)pireno , Canadá , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Receptores Proteína Tirosina Quinases
2.
J Cardiothorac Vasc Anesth ; 36(1): 258-274, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33744115

RESUMO

Transesophageal echocardiography (TEE) has become an integral part in helping to diagnose, manage, and assess interventions in the cardiac operating room. Multiple guidelines have been created by the American Society of Echocardiography for performing a TEE examination for different cardiac pathologies. The operating room can provide unique challenges when performing a TEE examination, which include hemodynamic instability, time constraints, and use of general anesthesia. The Guideline for the use of TEE to assist in surgical decision- making in the operating room recently was published to provide a starting protocol for conducting a TEE examination for different cardiac surgeries and for using the information obtained to interpret and to communicate findings to the surgical team. This present narrative review focuses and expands upon the relevant portions for the cardiac anesthesiologist.


Assuntos
Anestesiologistas , Ecocardiografia Transesofagiana , Coração , Humanos , Monitorização Intraoperatória , Salas Cirúrgicas
3.
Molecules ; 27(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35458685

RESUMO

The increase in ß-lactam-resistant Gram-negative bacteria is a severe recurrent problem in the food industry for both producers and consumers. The development of nanotechnology and nanomaterial applications has transformed many features in food science. The antibacterial activity of zinc oxide nanoparticles (ZnO NPs) and their mechanism of action on ß-lactam-resistant Gram-negative food pathogens, such as Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Serratia marcescens, Klebsiella pneumoniae, and Proteus mirabilis, are investigated in the present paper. The study results demonstrate that ZnO NPs possesses broad-spectrum action against these ß-lactamase-producing strains. The minimal inhibitory and minimal bactericidal concentrations vary from 0.04 to 0.08 and 0.12 to 0.24 mg/mL, respectively. The ZnO NPs elevate the level of reactive oxygen species (ROS) and malondialdehyde in the bacterial cells as membrane lipid peroxidation. It has been confirmed from the transmission electron microscopy image of the treated bacterial cells that ZnO NPs diminish the permeable membrane, denature the intracellular proteins, cause DNA damage, and cause membrane leakage. Based on these findings, the action of ZnO NPs has been attributed to the fact that broad-spectrum antibacterial action against ß-lactam-resistant Gram-negative food pathogens is mediated by Zn2+ ion-induced oxidative stress, actions via lipid peroxidation and membrane damage, subsequently resulting in depletion, leading to ß-lactamase enzyme inhibition, intracellular protein inactivation, DNA damage, and eventually cell death. Based on the findings of the present study, ZnO NPs can be recommended as potent broad-spectrum antibacterial agents against ß-lactam-resistant Gram-negative pathogenic strains.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bactérias , Escherichia coli , Testes de Sensibilidade Microbiana , Óxido de Zinco/metabolismo , Óxido de Zinco/farmacologia , beta-Lactamases/metabolismo , beta-Lactamas/metabolismo
4.
Ann Surg Oncol ; 28(9): 4816-4826, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33866473

RESUMO

INTRODUCTION: The COVID-19 pandemic has resulted in unparalleled changes to patient care, including the suspension of cancer surgery. Concerns regarding COVID-19-related risks to patients and healthcare workers with the re-introduction of major complex minimally invasive and open surgery have been raised. This study examines the COVID-19 related risks to patients and healthcare workers following the re-introduction of major oesophago-gastric (EG) surgery. PATIENTS AND METHODS: This was an international, multi-centre, observational study of consecutive patients treated by open and minimally invasive oesophagectomy and gastrectomy for malignant or benign disease. Patients were recruited from nine European centres serving regions with a high population incidence of COVID-19 between 1 May and 1 July 2020. The primary endpoint was 30-day COVID-19-related mortality. All staff involved in the operative care of patients were invited to complete a health-related survey to assess the incidence of COVID-19 in this group. RESULTS: In total, 158 patients were included in the study (71 oesophagectomy, 82 gastrectomy). Overall, 87 patients (57%) underwent MIS (59 oesophagectomy, 28 gastrectomy). A total of 403 staff were eligible for inclusion, of whom 313 (78%) completed the health survey. Approaches to mitigate against the risks of COVID-19 for patients and staff varied amongst centres. No patients developed COVID-19 in the post-operative period. Two healthcare workers developed self-limiting COVID-19. CONCLUSIONS: Precautions to minimise the risk of COVID-19 infection have enabled the safe re-introduction of minimally invasive and open EG surgery for both patients and staff. Further studies are necessary to determine the minimum requirements for mitigations against COVID-19.


Assuntos
COVID-19 , Pandemias , Pessoal de Saúde , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , SARS-CoV-2
5.
BMC Anesthesiol ; 21(1): 151, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006242

RESUMO

BACKGROUND: Anesthetic management of an adult with failing Fontan physiology is complicated given inherent anatomical and physiological alterations. Neurosurgical interventions including thromboembolectomy may be particularly challenging given importance of blood pressure control and cerebral perfusion. CASE PRESENTATION: We describe a 29 year old patient born with double outlet right ventricle (DORV) with mitral valve atresia who after multi-staged surgeries earlier in life, presented with failing Fontan physiology. She was admitted to the hospital almost 29 years after her initial surgeries to undergo workup for a dual heart and liver transplant in the context of a failing Fontan with elevated end diastolic pressures, NYHA III heart failure symptoms, and liver cirrhosis from congestive hepatopathy. During the workup in the context of holding anticoagulation for invasive procedures, she developed a middle cerebral artery (MCA) stroke requiring a thromboembolectomy via left carotid artery approach. DISCUSSION AND CONCLUSIONS: This case posed many challenges to the anesthesiologist including airway control, hemodynamic and cardiopulmonary monitoring, evaluation of perfusion, vascular access, and management of anticoagulation in an adult patient in heart and liver failure with Fontan physiology undergoing thromboembolectomy for MCA embolic stroke.


Assuntos
Artérias Carótidas/fisiopatologia , Técnica de Fontan , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Tromboembolia/cirurgia , Adulto , Artérias Carótidas/diagnóstico por imagem , Evolução Fatal , Feminino , Cardiopatias Congênitas/complicações , Insuficiência Cardíaca/complicações , Humanos , Cirrose Hepática/complicações , Ultrassonografia de Intervenção/métodos
6.
BMC Anesthesiol ; 21(1): 258, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34706655

RESUMO

BACKGROUND: The World Symposium of Pulmonary Hypertension in 2018, updated the definition of pulmonary hypertension (PH) as mean pulmonary artery pressures (PAP) > 20 mmHg. Pulmonary venous hypertension secondary to left-heart disease, constitutes the most common cause of PH, and the determination of a co-existent pre-capillary (primary) PH becomes paramount, particularly at the moment of evaluating and managing patients with heart failure. Pulmonary artery pressures above the systemic pressures define supra-systemic PH and generally leads to frank right ventricular failure and high mortality. CASE PRESENTATION: We present the perioperative management of a patient with rheumatic mitral valve disease, initially found to have severe PH due to pulmonary venous hypertension, who underwent percutaneous mitral balloon valvuloplasty complicated with mitral chordae rupture, severe mitral regurgitation and supra-systemic PH. Multiple medical therapies and an intra-aortic balloon pump were used as means of non-surgical management of this complication. CONCLUSIONS: This case report illustrates the perioperative implications of combined pre- and post-capillary PH and supra-systemic PH, as this has not been widely discussed in previous literature. A thorough literature review of the clinical characteristics of PH, methods to determine co-existent pre- and post-capillary PH components, as well as concomitant right ventricular failure is presented. Severe PH has known detrimental effects on the hemodynamic status of patients, which can ultimately lead to a decrease in effective cardiac output and poor tissue perfusion.


Assuntos
Valvuloplastia com Balão , Hipertensão Pulmonar/terapia , Estenose da Valva Mitral/terapia , Cordas Tendinosas/lesões , Feminino , Humanos , Balão Intra-Aórtico , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/terapia , Pirimidinas/uso terapêutico , Cardiopatia Reumática/complicações , Cardiopatia Reumática/terapia , Ruptura Espontânea , Sulfonamidas/uso terapêutico , Vasodilatadores/uso terapêutico
7.
J Cardiothorac Vasc Anesth ; 35(5): 1469-1476, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33376071

RESUMO

US Food and Drug Administration approval of the edge-to-edge clip repair device (MitraClip; Abbott Laboratories, Abbott Park, IL) in 2013 led to wide adoption of the device for treatment of severe primary mitral regurgitation in patients unsuitable for surgery. Demonstration of favorable outcomes in the setting of secondary mitral regurgitation by the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation (COAPT) trial in 2019 provided an additional impetus to the transcatheter mitral interventional program. The role of the cardiac anesthesia service also is expanding to echocardiography services for these patients outside of the procedure room. Moreover, cardiac anesthesiologists serve on the multidisciplinary team that is involved in clinical decision-making pertaining to patient selection, optimization, and intervention. This document has direct implications for the cardiac anesthesiologist involved in the care of these patients because a broader understanding of pertinent issues is essential to function as an effective clinical member within the multidisciplinary team. As such, this narrative review serves to highlight the salient features of the "2019 AATS/ACC/SCAI/STS Expert Consensus Systems of Care Document: Operator and Institutional Recommendations and Requirements for Transcatheter Mitral Valve Intervention: A Joint Report of the American Association for Thoracic Surgery, the American College of Cardiology, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons," focuses on issues pertinent to the cardiac anesthesiologist, and provides an outline for the clinical context and evolution of transcatheter mitral valve interventions.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Cirurgia Torácica , Anestesiologistas , Cateterismo Cardíaco , Consenso , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Resultado do Tratamento , Estados Unidos
8.
Molecules ; 26(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34885955

RESUMO

Rosemary (Rosmarinus officinalis) and basil (Ocimum sanctum Linn) are mostly used as herbal teas, made by steeping whole or ground herbs in boiling water. Hence, it is important to know the effect of boiling time on the bioactivity of these herbs. The effect of different boiling times (5, 10, and 15 min) on the antioxidant and antimicrobial properties, and some selected phenolic compounds of these herbs was examined in this study. Experimental results revealed that basil displayed the highest total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant activity when it was boiled for 5 min, and the lowest TPC was obtained when it was boiled for 15 min. On the other hand, rosemary had the highest TPC, TFC, and antioxidant potential after being boiled for 15 min, while it had the lowest after being boiled for 5 min. There was no growth inhibition of rosemary extracts against gram-negative bacteria, whereas higher growth inhibition was observed against gram-positive bacteria. The MIC and MBC of rosemary ethanolic extract against Listeria monocytogenes were 5 and 5 mg/mL and against B. subtilis were 10 and 10 mg/mL, respectively. While MIC and MBC of methanolic extract against L. monocytogenes were 5 and 5 mg/mL and against Bacillus subtilis were and 5 and 5 mg/mL, respectively. Salicylic acid was the most abundant (324.7 mg/100 g dry weight (dw)) phenolic compound in the rosemary sample boiled for 5 min, and acetyl salicylic acid was the most abundant (122.61 mg/10 g dw) phenolic compound in the basil sample boiled for 15 min.


Assuntos
Anti-Infecciosos/química , Ocimum basilicum/química , Rosmarinus/química , Chás de Ervas , Anti-Infecciosos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Manipulação de Alimentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Temperatura Alta , Plantas Medicinais/química , Polifenóis/química , Polifenóis/farmacologia , Chás de Ervas/análise
9.
J Surg Oncol ; 122(4): 691-698, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32488872

RESUMO

BACKGROUND AND OBJECTIVES: The aim of surgical treatment of gastrointestinal stromal tumors (GIST) is a microscopically complete resection. Initial indications for laparoscopic surgery were limited to smaller tumors, in favorable locations. Over time, indications for minimal invasive surgery (MIS) have expanded, however concerns remain when considering resection of larger GISTs. Our aims were to assess the utility of robotic resection of gastric GISTs for challenging tumors. METHODS: GIST resections, in this study were performed using the Intuitive Da Vinci Surgical Xi System. GIST's were considered challenging if tumor size was >50 mm at the time of surgery and/or the location of the tumor was type II, III, or IV using Privette/Al-Thanai classification. RESULTS: Robotic resections were performed on 12 consecutive patients, 83% were considered challenging cases, 6 out of 12 for location and 5 out of 12 for size. Initial median tumor size on imaging was 53.7 mm, and post-imatinib was 45.8 mm. All tumors were removed with clear margins (R0) via wedge resections, with no complications. Median operative time was 192 minutes (95-250). Length of hospital stay was 2 days (2-6). CONCLUSIONS: Robotic resection of gastric GIST's appears oncologically safe, and may expand the benefits of MIS to a greater cohort of complex cases.

10.
Bioinformatics ; 34(4): 660-668, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29028931

RESUMO

Motivation: A large number of protein sequences are becoming available through the application of novel high-throughput sequencing technologies. Experimental functional characterization of these proteins is time-consuming and expensive, and is often only done rigorously for few selected model organisms. Computational function prediction approaches have been suggested to fill this gap. The functions of proteins are classified using the Gene Ontology (GO), which contains over 40 000 classes. Additionally, proteins have multiple functions, making function prediction a large-scale, multi-class, multi-label problem. Results: We have developed a novel method to predict protein function from sequence. We use deep learning to learn features from protein sequences as well as a cross-species protein-protein interaction network. Our approach specifically outputs information in the structure of the GO and utilizes the dependencies between GO classes as background information to construct a deep learning model. We evaluate our method using the standards established by the Computational Assessment of Function Annotation (CAFA) and demonstrate a significant improvement over baseline methods such as BLAST, in particular for predicting cellular locations. Availability and implementation: Web server: http://deepgo.bio2vec.net, Source code: https://github.com/bio-ontology-research-group/deepgo. Contact: robert.hoehndorf@kaust.edu.sa. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Ontologia Genética , Mapas de Interação de Proteínas , Proteínas/metabolismo , Análise de Sequência de Proteína/métodos , Software , Aprendizado de Máquina Supervisionado , Animais , Bactérias/metabolismo , Biologia Computacional/métodos , Eucariotos/metabolismo , Humanos , Proteínas/fisiologia
12.
J Neuroophthalmol ; 36(1): 73-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26628337

RESUMO

Bilateral, simultaneous optic nerve sheath infiltration as a manifestation of leukemia relapse is very rare. A 45-year-old woman with chronic myelogenous leukemia was successfully treated to cytogenetic bone marrow remission 1 year previously and maintained on imatinib. She developed total bilateral blindness with marked, bilateral optic disc edema and evidence of bilateral optic nerve infiltration on magnetic resonance imaging. Cerebrospinal fluid cytology confirmed central nervous system (CNS) blast crisis. She recovered visual acuity of 20/20 in the right eye, and 20/25 in the left eye with salvage systemic and intrathecal chemotherapy before radiation therapy. Our report underscores the importance of timely and aggressive intervention of blast crisis of the CNS and the need for CNS penetrating induction and maintenance therapy.


Assuntos
Crise Blástica/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Infiltração Leucêmica/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias do Nervo Óptico/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Crise Blástica/tratamento farmacológico , Crise Blástica/genética , Feminino , Genes abl/genética , Humanos , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Infiltração Leucêmica/tratamento farmacológico , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Neoplasias do Nervo Óptico/tratamento farmacológico , Neoplasias do Nervo Óptico/genética , Reação em Cadeia da Polimerase em Tempo Real , Terapia de Salvação , Tomografia de Coerência Óptica
13.
PLoS One ; 19(9): e0310492, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39316574

RESUMO

Liposils, synthesized via the liposome templating method, offer a promising strategy for enhancing liposome stability by employing a silica coating. This study focuses on the development of nanocarriers utilizing silica-coated nanoliposomes for encapsulating the poorly water-soluble drug, ibrutinib. Ibrutinib-loaded nanoliposomes were meticulously formulated using the reverse-phase evaporation technique, serving as templates for silica coating, resulting in spherical liposils with an average size of approximately 240 nanometers. Comprehensive characterization of the liposil's physical and chemical properties was conducted using various analytical methods, including dynamic light scattering, transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction analysis. Liposils demonstrated superior performance compared to ibrutinib-loaded nanoliposomes, showing sustained drug release profiles in simulated intestinal fluids and resistance to simulated gastric fluid, as confirmed by dissolution studies. Moreover, ibrutinib liposils exhibited a significant increase in half-life (4.08-fold) and notable improvement in bioavailability (3.12-fold) compared to ibrutinib suspensions, as determined by pharmacokinetic studies in rats. These findings underscore the potential of liposils as nanocarriers for orally delivering poorly water-soluble drugs, offering enhanced stability and controlled release profiles, thereby improving bioavailability prospects and therapeutic efficacy. This approach holds promise for addressing challenges associated with the oral administration of drugs with limited solubility, thereby advancing drug delivery technologies and clinical outcomes in pharmaceutical research and development.


Assuntos
Adenina , Disponibilidade Biológica , Lipossomos , Piperidinas , Pirazóis , Pirimidinas , Adenina/farmacocinética , Adenina/análogos & derivados , Adenina/administração & dosagem , Adenina/química , Piperidinas/farmacocinética , Piperidinas/administração & dosagem , Piperidinas/química , Animais , Administração Oral , Lipossomos/química , Pirimidinas/farmacocinética , Pirimidinas/administração & dosagem , Pirimidinas/química , Ratos , Pirazóis/farmacocinética , Pirazóis/administração & dosagem , Pirazóis/química , Masculino , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Nanopartículas/química , Ratos Sprague-Dawley , Dióxido de Silício/química
14.
Brain Lang ; 249: 105378, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38198905

RESUMO

Speech impairments are one of the common symptoms of individuals with Parkinson's disease (PD). However, little is known about the underlying neuroanatomical structural deficits specifically in the basal ganglia-thalamocortical (BGTC) loop in the speech deficits of PD. Here we investigated white matter differences in PD using probabilistic tractography. Diffusion tensor imaging data were downloaded from the Parkinson's Progression Markers Initiative database. We included three groups of participants: 20 PD individuals with speech deficits, 20 PD individuals without speech deficits, and 20 age- and gender-matched control participants. Overall, PD individuals with speech deficits had higher mean diffusivity in the BGTC pathway in the left hemisphere compared with PD individuals without speech deficits. The present study exhibits that there may be a distinct pathophysiological profile of white matter for speech deficits in PD.


Assuntos
Doença de Parkinson , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Fala , Imagem de Difusão por Ressonância Magnética
15.
Cureus ; 16(1): e53091, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38414694

RESUMO

BACKGROUND:  An assessment of Suaeda monoica extract's antimicrobial and antioxidant properties was undertaken in light of its possible application as an oral care product. The maintenance of optimal dental health is just as important as overall wellness. Food particles become trapped in the mouth cavity, making it easy for oral bacteria to infect. AIM:  The study sought to ascertain the antibacterial and antioxidant properties of salt marsh Suaeda monoica extract. MATERIALS AND METHODS:  Leaves of Suaeda monoica, collected, dried and powdered, were dissolved in 70% methanol and the extract of 25-100 µg/ml was analyzed for antioxidant activity through total antioxidant assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and total reducing power. Suaeda monoica antibacterial activity was also performed and the minimum inhibitory concentration was determined for 75 µg/ml, 100µg/ml, and 150 µg/ml concentrations and tetracycline in 10mcg/disc as a control against three different oral pathogens: Staphylococcus mutans, Streptococcus aureus, and Klebsiella spp. RESULTS:  At varying concentrations of 75 mg/ml to 150 mg/ml, Suaeda monoica extracts are efficacious with varying concentrations against the investigated bacterial strains. In the present study, in the DPPH assay, total reducing power, and total antioxidant activity assay, there was an increase in inhibitory percentage as the concentration increased from 25-100 µg/ml, showing maximum inhibition at 100 µg/ml concentration. CONCLUSION:  The results of the investigation show that Suaeda monoica has significant antibacterial and antioxidant activity in a concentration-dependent manner and can be potentially used as an oral care agent after it is assessed for clinical use.

16.
Cureus ; 16(8): e67890, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39328706

RESUMO

Introduction Manganese(III) oxide (Mn2O3) is a transition metal oxide that has gained significant attention due to its unique properties and potential applications in various fields, including catalysis, energy storage, and sensing. Dopamine, a neurotransmitter in the human brain, plays a crucial role in regulating several physiological processes as its detection is important in areas such as medical diagnostics and neurochemistry. The synthesis of Mn2O3 can be achieved through methods like precipitation, hydrothermal synthesis, or solid-state reactions. Aims The objective of this study is to synthesize Mn2O3, characterize its structure and morphology, and investigate its electrochemical properties toward dopamine. Materials and methods Materials used included manganese sulfate (MnSO4), potassium permanganate, deionized water, a Teflon steel autoclave, and a hot air oven. For the synthesis of a hierarchical Mn2O3 rodlike shape, MnSO4•H2O (8 mmol) and potassium permanganate (8 mmol) were firstly dissolved in deionized water (40 mL) by stirring, which was then transferred to a Teflon-lined stainless steel autoclave (50 mL). This autoclave was sealed and maintained at 90℃ for six hours. Finally, the resultant Mn2O3 rods were collected by filtration, washed with distilled water and absolute ethanol for several times, and dried in air at 80℃. Mn2O3 rods were obtained by the calcinations of the as-prepared Mn2O3 rods at different temperatures. When Mn2O3 rods were treated at 600℃ for six hours in air, Mn2O3 rods could be collected. Results The X-ray diffraction (XRD) analysis shows that Mn2O3 is crystalline in structure and it matched with that of the Joint Committee on Powder Diffraction Standards (JCPDS). The field emission scanning electron microscopy (FE-SEM) shows the morphology of Mn2O3 is a particle with the size of 100 nm. Cyclic voltammetry response shows that compared to bare electrode, modified electrode shows the higher current response which indicates the sensing ability of the dopamine molecule. Conclusion  Mn2O3 was prepared using a hydrothermal technique, and the formation of nanoparticles (NPs) was verified through XRD, while the morphology was examined using FE-SEM. The Mn2O3 obtained was utilized in the detection of electrochemical dopamine, showing promise in the development of effective dopamine sensors. This study sets the stage for the integration of Mn2O3 into microfluidic systems for ongoing dopamine monitoring, presenting novel prospects for healthcare and neurochemical investigations. The exploration of various surface engineering approaches may additionally improve the electrochemical capabilities of Mn2O3 for the advancement of sensor technology.

17.
Cureus ; 16(4): e58709, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38779263

RESUMO

Background Electrochemical sensing is a versatile field that uses electrochemistry concepts to detect and measure various substances. It finds applications in clinical diagnostics and environmental monitoring. Scientists are currently working on creating reliable electrochemical sensing devices that can accurately detect ascorbic acid. Iron sulfide (FeS) has emerged as a promising material for these sensors due to its excellent electrical conductivity, catalytic activity, and stability.  Materials and methods The FeS nanoparticles were synthesized through the hydrothermal method of synthesis. The glassy carbon electrode (GCE) with a surface area of 0.071 cm2 was modified with FeS before the working electrode was mechanically polished with 1 µm, 0.3 µm, and 0.05 µm alumina pastes for mirror finishing. Then it was subjected to ultrasonication in double distilled water for a few minutes to clean the surface of GCE. The FeS suspension was prepared by dispersing 5 mg of FeS in 10 mL of ethanol during 20 minutes of ultrasonic agitation then the GCE was coated with 10 µL of the suspension by drop coating method and dried in air. Results In this study, FeS nanoparticles were synthesized by the hydrothermal method of synthesis, and it was tested for their electrochemical sensing properties by various tests. Based on the field emission-scanning electron microscope (FE-SEM) analysis, scan rate effect test, cyclic voltammetric test, X-ray diffraction (XRD), and energy-dispersive X-ray (EDX) spectroscopy analysis done and results obtained, it was seen that the synthesized FeS nanoparticles are highly pure and have a crystalline structure. FeS has an even morphology. The synthesized particles also showed highly sensitive and specific sensing toward ascorbic acid when compared to unmodified 10.1 µA electrodes with a sensing value of 12.51 µA, thereby fulfilling the aim of this study. Conclusion Based on the outcomes of the diverse tests carried out, it is evident that the sample displayed a high crystalline nature as indicated by the XRD test. Additionally, the sample exhibited a uniform morphology, exceptional stability, and remarkable sensitivity. The developed FeS-based electrochemical sensor was found to be exceptionally pure and showed excellent performance, showcasing both high sensitivity and selectivity toward ascorbic acid.

18.
Cureus ; 16(4): e58939, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38800305

RESUMO

Background Heliotropium bacciferum, often known as wild heliotrope or wild quailplant, is a flowering plant from the borage family. This study examines the anti-metastatic impact of H. bacciferum on Michigan Cancer Foundation-7 (MCF-7) breast cancer cells and its ability to disrupt signaling pathways. Aim To explore the anti-metastatic effect of H. bacciferum on the MCF-7 breast cancer cell line. Materials and methods For this research, MCF-7 breast cancer cells were used. Cells were cultured and subjected to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, as well as gene expression analysis for glycogen synthase kinase 3 beta (GSK3ß), wingless-related integration site 2 (Wnt2), and ß-catenin. The plant extract was tested to determine if it successfully blocked the signalling pathway or not.  Results The MTT test was performed to study the cytotoxic impact of H. bacciferum. At an increasing concentration of 100 µg/mL, the extract inhibited growth by 55%, whereas at 150 µg/mL, it inhibited growth by 52.5%. Maximum inhibition was seen at 150 µg/mL. H. bacciferum suppressed the GSK3ß and Wnt2 signaling pathways in MCF-7 breast cancer cell lines, acting as an anti-metastatic and anticancer agent. The heliotrine compound in H. bacciferum showed high binding energy to metastatic targets such as GSK3ß, Wnt2, and ß-catenin. Moreover, chemical absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties also support the study. Conclusion In this study, we can infer that H. bacciferum has a favourable anticancer impact on MCF-7 breast cancer cell lines and may be utilised as an anticancer drug against breast cancer cells. It can also be further evaluated for different breast cancers and cell lines.

19.
Cureus ; 16(9): e70481, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39479056

RESUMO

Introduction Dopamine serves an essential function as a neurotransmitter, influencing the regulation of movement, cognitive processes, and emotional states. The identification of abnormal dopamine levels is critical for clinical diagnoses and scientific research, given its links to various disorders, including depression, schizophrenia, and Parkinson's disease. The distinctive electrochemical characteristics, stability, and broad bandgap of zinc sulfide (ZnS) nanostructures render them particularly fascinating. The hydrothermal method is recognized as an effective and economical approach for the fabrication of ZnS nanostructures, exhibiting a range of morphologies. Utilizing this method to create ZnS nanostructures leads to the formation of structures characterized by extensive surface areas, hierarchical designs, and improved electrochemical properties. Aim The objective is to examine the electrochemical characteristics of ZnS starfish-shaped nanostructures produced through the hydrothermal technique and to assess their viability as a sensing platform for dopamine detection. Materials and methods To synthesize ZnS nanoflowers, stoichiometric amounts of transition metal salts were prepared: 10 mM of Zn(NO3)2•3H2O and 30 mM of sodium thiosulfate (Na2S2O3•5H2O) were dissolved in 30 mL of deionized water and stirred for 20 minutes. The solutions were then combined and transferred into a 100 mL Teflon autoclave reactor, which was heated at 200 °C for 12 hours in a furnace. This process utilized the hydrothermal technique to produce the desired ZnS nanoflowers. Result The crystalline arrangement of ZnS was validated by X-ray diffraction (XRD) analysis, aligning with the Joint Committee on Powder Diffraction Standards (JCPDS). Moreover, field emission scanning electron microscopy (FE-SEM) illustrated the particle morphology of ZnS, showing a range between 200 and 500 nm size. Additionally, the cyclic voltammetry results indicated that the modified electrode produced a greater current response than the bare electrode, highlighting its improved sensitivity to dopamine molecules. Conclusion ZnS nanoparticles were synthesized via a hydrothermal method and characterized using XRD and FE-SEM. These nanoparticles were used for electrochemical dopamine detection, showing potential for advanced sensing platforms. Integrating ZnS into microfluidic devices enables real-time dopamine monitoring, opening new possibilities for healthcare and neurochemical research. Exploring surface engineering techniques could further enhance the electrochemical performance of ZnS-based sensors.

20.
Cureus ; 16(3): e56300, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38629020

RESUMO

Background This study investigates Merremia emarginata's curative effectiveness against colon cancer cells. M. emarginata, often known as Elika jemudu, is a Convolvulaceae family plant. The inhibitory ability of anticancer herbal extracts against cancer cell growth and mediators is tested.  Aim This study aims to evaluate the potent anticancer activity of M. emarginata against colon cancer cell line (HT-29). Materials and methods M. emarginata leaves were gathered and processed using solvent extraction. Anticancer activity on colon cancer cells was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and cysteine aspartic acid protease-3 (caspase 3), B-cell lymphoma 2 (Bcl-2), and B-cell lymphoma-extra large (Bcl-xL) mRNA expressions. The data was reported as the mean ± SD of three separate experiments done in triplicate. The statistical analysis was carried out using one-way analysis of variance (ANOVA), with a p-value less than 0.05 indicating statistical significance. Results The cell viability test showed a gradual decrease in cell growth and proliferation as the concentration increased. The ethanolic extract of M. emarginata was found to be cytotoxic against colon caller cell lines. The extract was able to induce apoptosis of cancer as revealed by Bcl-2, Bcl-xL, and caspase-3 (p<0.05 and p<0.001) signaling pathways. Conclusion M. emarginata extracts showed good anticancer activity against colon cancer cell lines. Further work is required to establish and identify the chemical constituent responsible for its anticancer activity.

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