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1.
ChemSusChem ; : e202400027, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588020

RESUMO

An in-depth investigation was conducted on a promising composite material (BiVO4/TiO2), focusing on its potential toxicity, photoinduced catalytic properties, as well as its antibiofilm and antimicrobial functionalities. The preparation process involved the synthesis of 2D-TiO2 using the lyophilization method, which was subsequently functionalized with sphere-like BiVO4. Finally, we developed BiVO4/TiO2 S-scheme heterojunctions which can greatly promote the separation of electron-hole pairs to achieve high photocatalytic performance. The evaluation of concentration- and time-dependent viability inhibition was performed on human lung carcinoma epithelial A549 cells. This assessment included the estimation of glutathione levels and mitochondrial dehydrogenase activity. Significantly, the BiVO4/TiO2 composite demonstrated minimal toxicity towards A549 cells. Impressively, the BiVO4/TiO2 composite exhibited notable photocatalytic performance in the degradation of rhodamine B (k =0.135 min-1) and phenol (k = 0.016 min-1). In terms of photoinduced antimicrobial performance, the composite effectively inactivated both gram-negative E. coli and gram-positive E. faecalis bacteria upon 60-min of UV-A light exposure, resulting in a significant log6(log10CFU/mL) reduction in bacterial count. These promising results can be attributed to the unique 2D morphology of TiO2 modified by sphere-like BiVO4, leading to an increased generation of (intracellular)hydroxyl radicals, which plays a crucial role in treatments of both organic pollutants and bacteria.

2.
Cureus ; 16(1): e52511, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38371088

RESUMO

Cancer involves intricate pathological mechanisms marked by complexities such as cytotoxicity, drug resistance, stem cell proliferation, and inadequate specificity in current chemotherapy approaches. Cancer therapy has embraced diverse nanomaterials renowned for their unique magnetic, electrical, and optical properties to address these challenges. Despite the expanding corpus of knowledge in this area, there has been less advancement in approving nano drugs for use in clinical settings. Nanotechnology, and more especially the development of intelligent nanomaterials, has had a profound impact on cancer research and treatment in recent years. Due to their large surface area, nanoparticles can adeptly encapsulate diverse compounds. Furthermore, the modification of nanoparticles is achievable through a broad spectrum of bio-based substrates, including DNA, aptamers, RNA, and antibodies. This functionalization substantially enhances their theranostic capabilities. Nanomaterials originating from biological sources outperform their conventionally created counterparts, offering advantages such as reduced toxicity, lower manufacturing costs, and enhanced efficiency. This review uses carbon nanomaterials, including graphene-based materials, carbon nanotubes (CNTs) based nanomaterials, and carbon quantum dots (CQDs), to give a complete overview of various methods used in cancer theranostics. We also discussed their advantages and limitations in cancer diagnosis and treatment settings. Carbon nanomaterials might significantly improve cancer theranostics and pave the way for fresh tumor diagnosis and treatment approaches. More study is needed to determine whether using nano-carriers for targeted medicine delivery may increase material utilization. More insight is required to explore the correlation between heightened cytotoxicity and retention resulting from increased permeability.

4.
Brain Sci ; 13(9)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37759920

RESUMO

The independent detection and classification of brain malignancies using magnetic resonance imaging (MRI) can present challenges and the potential for error due to the intricate nature and time-consuming process involved. The complexity of the brain tumor identification process primarily stems from the need for a comprehensive evaluation spanning multiple modules. The advancement of deep learning (DL) has facilitated the emergence of automated medical image processing and diagnostics solutions, thereby offering a potential resolution to this issue. Convolutional neural networks (CNNs) represent a prominent methodology in visual learning and image categorization. The present study introduces a novel methodology integrating image enhancement techniques, specifically, Gaussian-blur-based sharpening and Adaptive Histogram Equalization using CLAHE, with the proposed model. This approach aims to effectively classify different categories of brain tumors, including glioma, meningioma, and pituitary tumor, as well as cases without tumors. The algorithm underwent comprehensive testing using benchmarked data from the published literature, and the results were compared with pre-trained models, including VGG16, ResNet50, VGG19, InceptionV3, and MobileNetV2. The experimental findings of the proposed method demonstrated a noteworthy classification accuracy of 97.84%, a precision success rate of 97.85%, a recall rate of 97.85%, and an F1-score of 97.90%. The results presented in this study showcase the exceptional accuracy of the proposed methodology in accurately classifying the most commonly occurring brain tumor types. The technique exhibited commendable generalization properties, rendering it a valuable asset in medicine for aiding physicians in making precise and proficient brain diagnoses.

5.
Sci Rep ; 13(1): 15731, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735227

RESUMO

Amyloid beta (Aß) aggregation and tau hyper phosphorylation (p-tau) are key molecular factors in Alzheimer's disease (AD). The abnormal formation and accumulation of Aß and p-tau lead to the formation of amyloid plaques and neurofibrillary tangles (NFTs) which ultimately leads to neuroinflammation and neurodegeneration. ß- and γ-secretases produce Aß peptides via the amyloidogenic pathway, and several kinases are involved in tau phosphorylation. Exosomes, a recently developed method of intercellular communication, derived from neuronal stem cells (NSC-exos), are intriguing therapeutic options for AD. Exosomes have ability to cross the BBB hence highly recommended for brain related diseases and disorders. In the current study, we examined how NSC-exos could protect human neuroblastoma cells SH-SY5Y (ATCC CRL-2266). NSC-exos were derived from Human neural stem cells (ATCC-BYS012) by ultracentrifugation and the therapeutic effects of the NSC-exos were then investigated in vitro. NSC-exos controlled the associated molecular processes to drastically lower Aß and p-tau. A dose dependent reduction in ß- and γ-secretase, acetylcholinesterase, GSK3ß, CDK5, and activated α-secretase activities was also seen. We further showed that BACE1, PSEN1, CDK5, and GSK-3ß mRNA expression was suppressed and downregulated, while ADAM10 mRNA was increased. NSC- Exos downregulate NF-B/ERK/JNK-related signaling pathways in activated glial cells HMC3 (ATCC-CRL-3304) and reduce inflammatory mediators such iNOS, IL-1ß, TNF-α, and IL-6, which are associated with neuronal inflammation. The NSC-exos therapy ameliorated the neurodegeneration of human neuroblastoma cells SH-SY5Y by enhancing viability. Overall, these findings support that exosomes produced from stem cells can be a neuro-protective therapy to alleviate AD pathology.


Assuntos
Doença de Alzheimer , Exossomos , Células-Tronco Neurais , Neuroblastoma , Humanos , Secretases da Proteína Precursora do Amiloide/genética , Glicogênio Sintase Quinase 3 beta , Doença de Alzheimer/terapia , Acetilcolinesterase , Peptídeos beta-Amiloides , Ácido Aspártico Endopeptidases/genética , Neuroblastoma/terapia
6.
ACS Appl Mater Interfaces ; 15(38): 45354-45366, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37702662

RESUMO

The present work aims to predict the degradation in the performance of a solid oxide fuel cell (SOFC) cathode owing to cation interdiffusion between the electrolyte and cathode and surface segregation. Cation migration in the (La0.60Sr0.40)0.95Co0.20Fe0.80O3-x (LSCF)-Gd0.10Ce0.90O1.95 (GDC) composite cathode is evaluated in relation to time up to 1000 h using scanning transmission electron microscopy (STEM)-energy-dispersive X-ray spectroscopy (EDXS). The resulting insulating phase formed within the GDC interlayer is quantified by means of the volume fraction using a two-dimensional (2D) image analysis technique. For the very first time, the amount of the insulating phase in the GDC interlayer is quantified, and the corresponding performance degradation of the LSCF cathode is predicted. Mathematical relationships are established for the estimation of degradation due to surface segregation of the cathode. The ohmic resistance between the cathode and the GDC interlayer/electrolyte interface and the polarization resistance of the cathode, characterized by electrochemical impedance spectroscopy (EIS), show an excellent match with the predicted results. The combined degradation analysis and modeling for the cathode lifetime prediction provide a systematic understanding of the time-dependent cation migration and segregation behavior.

7.
RSC Adv ; 13(36): 25029-25053, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37614791

RESUMO

Solid oxide fuel cells (SOFCs) are highly efficient, low-emission, and fuel-flexible energy conversion devices. However, their commercialization has lagged due to the lack of long-term durability. Among several performance degradation mechanisms, cathode degradation and elemental inter-diffusion of the electrolyte and cathode has been identified as the predominant factors. In the most common SOFC systems, a cobalt-based perovskite material is used, for example LSC or LSCF. These cobalt-based materials offer mixed conductivity and higher concentration of oxygen vacancies as compared to LSM at lower operating temperature leading to favorable reduction kinetics. However, the presence of cobalt results in higher cost, higher thermal expansion co-efficient (TEC) mismatch and most importantly leads to rapid degradation. Various elements like strontium, cobalt, cerium, chromium, or zirconium accumulate or deposit at the electrode-electrolyte interface, which results in sluggish reaction kinetics of the oxygen reduction reaction (ORR). These elements react to form secondary phases that have lower ionic and electronic conductivity, cover active reaction sites, and eventually lead to cell and system deterioration. Over the past decade, several studies have focused on preventative and protective measures to prolong SOFC lifetime which includes novel fabrication techniques, introduction of new layers, addition of thin films to block the cation transport. Such efforts to prevent the formation of insulating phases and decomposition of the cathode have resulted in a remarkable improvement in long-term stability. In this review paper, current research on leading mechanisms responsible for the degradation of cobaltite cathode of solid oxide fuel cell has been summarized and durability improvement strategies of cobalt-based SOFC cathodes have been discussed.

8.
Cureus ; 15(6): e41101, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37519523

RESUMO

Dyke-Davidoff-Masson syndrome (DDMS) is a rare congenital or acquired neurological disorder that most commonly affects the pediatric population but is also rarely reported in adults. DDMS results from brain injury in the intrauterine or early years of life. It is characterized by prominent cortical sulci, hyperpneumatization of the frontal sinus, unilateral cerebral hemiatrophy with ventricular dilation, and associated bony thickness of the cranial vault. Seizures and asymmetric hemiparesis are the most consistent findings in DDMS with facial asymmetry and mental retardation widely reported. Herein, we report a case of a 32-year-old female patient with DDMS presenting with a history of seizure and right-sided hemiparesis. Neuroimaging findings showed asymmetric cerebral encephalomalacia and gliosis with ex vacuo ventricular dilatation and calvarial diploic space widening. Our case report is unique in the sense that our patient presented with DDMS in adulthood with no signs of mental retardation or history of seizures during childhood and well-controlled seizures on monotherapy. Given the adult presentation of DDMS is unusual and rarely reported in the medical literature, our case report will help physicians to keep DDMS high on differential diagnoses in such cases. Awareness of the clinical features of DDMS on imaging can facilitate a timely and accurate diagnosis, thereby enabling appropriate and prompt management.

9.
Brain Sci ; 13(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37190567

RESUMO

Brain tumor classification is crucial for medical evaluation in computer-assisted diagnostics (CAD). However, manual diagnosis of brain tumors from magnetic resonance imaging (MRI) can be time-consuming and complex, leading to inaccurate detection and classification. This is mainly because brain tumor identification is a complex procedure that relies on different modules. The advancements in Deep Learning (DL) have assisted in the automated process of medical images and diagnostics for various medical conditions, which benefits the health sector. Convolutional Neural Network (CNN) is one of the most prominent DL methods for visual learning and image classification tasks. This study presents a novel CNN algorithm to classify the brain tumor types of glioma, meningioma, and pituitary. The algorithm was tested on benchmarked data and compared with the existing pre-trained VGG16, VGG19, ResNet50, MobileNetV2, and InceptionV3 algorithms reported in the literature. The experimental results have indicated a high classification accuracy of 98.04%, precision, recall, and f1-score success rate of 98%, respectively. The classification results proved that the most common kinds of brain tumors could be categorized with a high level of accuracy. The presented algorithm has good generalization capability and execution speed that can be helpful in the field of medicine to assist doctors in making prompt and accurate decisions associated with brain tumor diagnosis.

10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 3222-3226, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36085628

RESUMO

The retina is a unique tissue that extends the human brain in transmitting the incoming light into neural spikes. Researchers collaborating with domain experts proposed numerous deep networks to extract vessels from the retina; however, these techniques have the least response for micro-vessels. The proposed method has developed a stacked ensemble network approach with deep neural architectures for precise vessel extraction. Our method has used bi-directional LSTM for filling gaps in dis-joint vessels and applied W-Net for boundary refinement and emphasizing local regions to achieve better results for micro-vessels extraction. The platform has combined the strength of various networks to improve the automated screening process and has shown promising results on benchmark datasets.


Assuntos
Benchmarking , Retina , Biomarcadores , Encéfalo , Diagnóstico Precoce , Humanos
11.
Int J Nanomedicine ; 17: 4073-4085, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111313

RESUMO

Purpose: Recent advances in nanotechnology have given rise to the potential utilization of nanoparticles as food, nano-medicine/biomedicines. Patient: The study aimed to investigate the effects of nano-zinc oxide (nano-zinc) on the bio-assimilation of mineral (Zn) in mice, aged 3-6 weeks. Methods: ZnO nanoparticles were added to the basal diet as a supplement at amounts of 0.07, 0.14 and 0.21 mg/kg. The synthesized material was characterized by Fourier transform infrared spectrophotometer, particle size, scanning electron microscope, Thermogravimetric Analysis Thermal, X-ray diffraction spectrophotometer and Zeta potential. Results: In-vitro bioavailability of synthesized group ZnO (120 nm) was 43%, whereas for standard group ZnO (50 nm) was reported as 55%. In-vivo bioavailability of zinc oxide illustrated the maximum absorption level compared with the control. In-vivo toxicity was characterized as damage done to the liver and spleen tissues with a high dose of 0.21 mg/kg, while smaller doses indicated no toxic effects. Conclusion: The study provided important insights on the toxicological effects of ZnO nanoparticles, depending on dose rate and bio-assimilation, as well as particles, under various conditions (in-vitro and in-vivo). These findings will motivate further detailed research on nano-based medicine for alleviating malnutrition conditions.


Assuntos
Nanopartículas , Óxido de Zinco , Animais , Camundongos , Nanotecnologia , Tamanho da Partícula , Zinco , Óxido de Zinco/toxicidade
12.
Int J Mol Sci ; 23(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36142578

RESUMO

Saponins are natural compounds found in plants and have a diverse range of applications. However, the therapeutic potential of saponins in regulating cytotoxicity, angiogenesis, and inflammation in mammalian cells is yet to be explored. Here, we investigated the therapeutic effects of saponins from green tea by exploring the cytotoxic effects of saponins by inducing apoptosis in the human cancer cell lines hepatocellular carcinoma (HEPG2) and colorectal adenocarcinoma (HT29). The anti-angiogenesis effect of saponins was also investigated in human umbilical vein endothelial cells (HUVEC). We explored the ability of saponins to attenuate inflammation in a dose-dependent manner in normal human cells. It was found that saponins exhibit cytotoxic effects in cancer cells and not in normal cells at the same concentration. Cytotoxicity was measured by inducing apoptosis by enhancing caspase-3 (cas-3) activation and B-cell lymphoma-2 (Bcl-2)-associated X protein (BAX) gene expression and suppressing the antiapoptotic protein, Bcl-2. The inhibition of HUVEC proliferation was due to the suppression of the phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), vascular endothelial growth factor receptor-2 (VEGFR-2), and nuclear factor kappa B (NF-κB). We also observed the antioxidant potential of green tea-derived saponins against free radicals in reactive oxygen species (ROS)-induced cells. Here we observed that the saponins exhibited free radical scavenging activities and activated nuclear factorerythroid 2-related factor 2 (NRF-2) leading to the upregulation of antioxidant-related genes in human embryonic kidney 293 (HEK293) cells. Furthermore, we demonstrated that the anti-inflammatory effects were due to the suppression of pro-inflammatory cytokines interleukin (IL)-1ß, IL-6, tumor necrosis factor-alpha (TNF-α), and inducible nitric oxide synthase (iNOS) in HEK293 cells. The significance of the work is we are the first to report on the anti-cancer effects of saponins based on the anti-inflammatory, antioxidant, anti-angiogenesis, and apoptosis induction properties. In conclusion, green tea-derived saponins could be effective therapeutics for the treatment of cancer.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Saponinas , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Caspase 3/metabolismo , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Inflamação/tratamento farmacológico , Interleucina-6/metabolismo , Mamíferos/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saponinas/farmacologia , Saponinas/uso terapêutico , Chá , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteína X Associada a bcl-2/metabolismo
13.
Materials (Basel) ; 15(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35744284

RESUMO

Metal matrix composites (MMCs) have wide applications due to being lightweight, their high strength, and immense resistance to wear. To explore new generation materials like aluminum-based metal matrix composites (AMCs) for wide engineering applications, the present work aimed at investigating the effect of changes in composition, sintering time, and temperature on the hardness and surface roughness of AMCs containing SiC and ZrSiO4 in wt % of 5, 20, 30, and 40 binary and hybrid sample pallets. The samples have been prepared by powder metallurgy (PM) method under 1000 psi pressure. After compaction, the above pallets sintered at different temperatures ranging from 500 °C to 1100 °C with an increment of 200 °C and 15 min intervals for four levels of temperature and time, respectively. Afterwards, sensitivity analysis has been done by investigating the effect of chemical composition, sintering time, and sintering temperature of the binary and hybrid composites on hardness and surface roughness. Morphological studies on the composites were carried out using field emission scanning electron microscope (FESEM) with energy dispersive spectroscopy (EDS). It has been observed that hardness is increased by increasing the sintering temperature in the case of SiC, whereas surface roughness did not change much by changing the composition. Additionally, a rise in temperature lead to liquid-state sintering. SEM images obtained during the elemental analysis showed that porosity is generated within the samples after sintering due to the higher melting point of reinforcements compared to a base metal, i.e., aluminum. Mathematical equations have also been developed via regression analysis using Minitab and excel for the confirmation and validation of experimental data. Analysis of Variance (ANOVA) has also been done, and its tables are shown and discussed in the paper. Hence, the most optimized findings relating the changes in the composition of reinforcements, sintering temperature, and sintering time (input variables) with porosity, hardness, and surface roughness have been presented in the current study.

14.
Cardiovasc Revasc Med ; 43: 20-25, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35610139

RESUMO

Data regarding the clinical outcomes of transcatheter aortic valve replacement (TAVR) vs. surgical aortic valve replacement (SAVR) in cardiac amyloidosis are lacking. Our study aimed to look at the clinical outcomes of TAVR vs. SAVR in patients with cardiac amyloidosis. METHOD: We queried the National Inpatient Sample database for the years 2009-2014 using validated ICD-9-CM codes for TAVR and SAVR. Propensity score matching (1:1; PSM) was performed and in-hospital outcomes were compared between matched cohorts. RESULTS: Before PSM, the TAVR group had a higher hospitalization cost ($59,192 vs. $56,171.1, p = 0.001) and in-hospital mortality (4.24% vs. 3.27%, p = 0.001) compared to the SAVR group. After PSM, mortality (41.3% vs. 5.81%, p = 0.001) and hospitalization cost ($5907 vs. $6280, p = 0.001) was higher in the SAVR group. Length of stay was shorter in the TAVR group compared to SAVR group before (8.7 vs 11.4 p = 0.001) and after (8.7 vs 0.13.7, p = 0.001) PSM. After PSM, the incidence of acute myocardial infarction (10.10% vs. 17.57%, p = 0.001), acute kidney injury (20.67% vs. 31.40%, p = 0.001) and major bleeding (39.18% vs. 47.90%, p = 0.001) were higher in the SAVR group while the TAVR group had a higher incidence of the stroke (12.47% vs. 11.97%, p = 0.001), vascular complication (14.59% vs. 12.97%, p = 0.001), and permanent pacemaker implantation (10.45% vs. 8.48%, p = 0.001). CONCLUSION: In CA patients, in-hospital mortality and hospitalization costs were higher in the SAVR group than in the TAVR group, while the length of stay was shorter in the TAVR group.


Assuntos
Amiloidose , Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Amiloidose/etiologia , Amiloidose/cirurgia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Mortalidade Hospitalar , Humanos , Complicações Pós-Operatórias , Fatores de Risco , Resultado do Tratamento
15.
Molecules ; 27(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408478

RESUMO

Tauopathy is one of the major causes of neurodegenerative disorders and diseases such as Alzheimer's disease (AD). Hyperphosphorylation of tau proteins by various kinases leads to the formation of PHF and NFT and eventually results in tauopathy and AD; similarly, neuroinflammation also exaggerates and accelerates neuropathy and neurodegeneration. Natural products with anti-tauopathy and anti-neuroinflammatory effects are highly recommended as safe and feasible ways of preventing and /or treating neurodegenerative diseases, including AD. In the present study, we isolated theasaponin E1 from ethanol extract of green tea seed and evaluated its therapeutic inhibitory effects on tau hyper-phosphorylation and neuroinflammation in neuroblastoma (SHY-5Y) and glioblastoma (HTB2) cells, respectively, to elucidate the mechanism of the inhibitory effects. The expression of tau-generating and phosphorylation-promoting genes under the effects of theasaponin E1 were determined and assessed by RT- PCR, ELISA, and western blotting. It was found that theasaponin E1 reduced hyperphosphorylation of tau and Aß concentrations significantly, and dose-dependently, by suppressing the expression of GSK3 ß, CDK5, CAMII, MAPK, EPOE4(E4), and PICALM, and enhanced the expression of PP1, PP2A, and TREM2. According to the ELISA and western blotting results, the levels of APP, Aß, and p-tau were reduced by treatment with theasaponin E1. Moreover, theasaponin E1 reduced inflammation by suppressing the Nf-kB pathway and dose-dependently reducing the levels of inflammatory cytokines such as IL-1beta, IL-6, and TNF-alpha etc.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Saponinas , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Doenças Neuroinflamatórias , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fosforilação , Saponinas/farmacologia , Saponinas/uso terapêutico , Sementes/metabolismo , Chá , Proteínas tau/metabolismo
16.
Cardiovasc Revasc Med ; 42: 67-71, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35288044

RESUMO

PURPOSE: Complete heart block requiring permanent pacemaker can occur early following transcatheter aortic valve replacement (TAVR) due to mechanical compression of the aortic valve annulus and associated atrio-ventricular (AV) conduction system. Data are limited regarding late PM implantation after TAVR. The purpose of this study was to determine predictors of early vs. late PM implantation post-TAVR procedure. METHODS: Baseline characteristics of patients who required PM <7 days following TAVR were compared with patients who required a PM >7 days to 1 year following TAVR using Chi-Square and multivariate regression analysis. RESULTS: There were 362 TAVR patients, of which 39 (10.4%) received a PM after TAVR. Of these 18 (4.6%) patients required PM within 7 days after TAVR, and 21 (5.8%) required PM after 7 days and up to 1 year later. Right bundle branch block (RBBB) (OR 6.721, CI 2.3-36.9, p < 0.005) was a positive predictor of early PM placement. Left bundle branch block (LBBB) (OR = 3.5, CI 1.19-10.80, p-value < 0.05) and atrial fibrillation (AF) (OR = 3.5, 1.36-9.4 p < 0.05) were predictors for late PM. Early and late PM were associated with a longer median hospital stay compared to no PM (4.9 ± 4.86 days vs. 10.1 ± 10.04 days vs. 6.10 ± 6.02 days). The incidence of heart failure was higher in the late PM group. The overall motility was not increased in early and late PM compared to no PM. CONCLUSION: Patients requiring PM implant after TAVR was 10.4%, of which 5.8% need PM >7 days post-TAVR. RBBB is a predictor for early PM. AF and LBBB were predictors for late PM.


Assuntos
Estenose da Valva Aórtica , Bloqueio Atrioventricular , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Arritmias Cardíacas/terapia , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/terapia , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/etiologia , Bloqueio de Ramo/terapia , Humanos , Marca-Passo Artificial/efeitos adversos , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
18.
Eur Heart J Case Rep ; 6(2): ytac010, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35169679

RESUMO

BACKGROUND: The delayed development of a mitral valve annulus pseudoaneurysm is a rare and late complication of a native mitral abscess cavity. CASE SUMMARY: Currently, there are no documented cases of a pseudoaneurysm developing from an abscess cavity of the posterior annulus of the native mitral valve. We report a case of a patient who presented with worsening progressive shortness of breath that was found to be secondary to a pseudoaneurysm. This was detected by 2D echocardiogram and cardiac computed tomography angiography. DISCUSSION: In our case, the patient developed a late complication of a ventricular pseudoaneurysm originating from the mitral annular area of the abscess cavity. Per the surgical literature, one method to avoid the aforementioned complication is via cavity repair with a bovine patch.

19.
PLoS One ; 16(12): e0256562, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34936645

RESUMO

Pectinolytic enzymes or pectinases are synthesized naturally by numerous microbes and plants. These enzymes degrade various kinds of pectin which exist as the major component of the cell wall in plants. A pectinase gene encoding endo-polygalacturonase (endo-PGase) enzyme was isolated from Pectobacterium carotovorum a plant pathogenic strain of bacteria and successfully cloned into a secretion vector pHT43 having σA-dependent promoter for heterologous expression in Bacillus subtilis (WB800N).The desired PCR product was 1209bp which encoded an open reading frame of 402 amino acids. Recombinant proteins showed an estimated molecular weight of 48 kDa confirmed by sodium dodecyl sulphate-polyacrylamide-gel electrophoresis. Transformed B. subtilis competent cells harbouring the engineered pHT43 vector with the foreign endo-PGase gene were cultured in 2X-yeast extract tryptone medium and subsequently screened for enzyme activity at various temperatures and pH ranges. Optimal activity of recombinant endo-PGase was found at 40°C and pH 5.0. To assay the catalytic effect of metal ions, the recombinant enzyme was incubated with 1 mM concentration of various metal ions. Potassium chloride increased the enzyme activity while EDTA, Zn++ and Ca++, strongly inhibited the activity. The chromatographic analysis of enzymatic hydrolysates of polygalacturonic acid (PGA) and pectin substrates using HPLC and TLC revealed tri and tetra-galacturonates as the end products of recombinant endo-PGase hydrolysis. Conclusively, endo-PGase gene from the plant pathogenic strain was successfully expressed in Bacillus subtilis for the first time using pHT43 expression vector and could be assessed for enzyme production using a very simple medium with IPTG induction. These findings proposed that the Bacillus expression system might be safer to escape endotoxins for commercial enzyme production as compared to yeast and fungi. Additionally, the hydrolysis products generated by the recombinant endo-PGase activity offer their useful applications in food and beverage industry for quality products.


Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Engenharia Metabólica/métodos , Pectobacterium carotovorum/enzimologia , Poligalacturonase/metabolismo , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Ácidos Hexurônicos/metabolismo , Pectinas/metabolismo , Pectobacterium carotovorum/genética , Poligalacturonase/genética , Cloreto de Potássio/metabolismo , Regiões Promotoras Genéticas
20.
Biomed Res Int ; 2021: 2521273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34812408

RESUMO

Obesity is a public health problem characterized by increased body weight due to abnormal adipose tissue expansion. Bioactive compound consumption from the diet or intake of dietary supplements is one of the possible ways to control obesity. Natural products with adipogenesis-regulating potential act as obesity treatments. We evaluated the synergistic antiangiogenesis, antiadipogenic and antilipogenic efficacy of standardized rebaudioside A, sativoside, and theasaponin E1 formulations (RASE1) in vitro in human umbilical vein endothelial cells (HUVECs), 3T3-L1 preadipocytes respectively, and in vivo using a high-fat and carbohydrate diet-induced obesity mouse model. Orlistat was used as a positive control, while untreated cells and animals were normal controls (NCs). Adipose tissue, liver, and blood were analyzed after dissection. Extracted stevia compounds and green tea seed saponin E1 exhibited pronounced antiobesity effects when combined. RASE1 inhibited HUVEC proliferation and tube formation by suppressing VEGFR2, NF-κB, PIK3, and-catenin beta-1 expression levels. RASE1 inhibited 3T3-L1 adipocyte differentiation and lipid accumulation by downregulating adipogenesis- and lipogenesis-promoting genes. RASE1 oral administration reduced mouse body and body fat pad weight and blood cholesterol, TG, ALT, AST, glucose, insulin, and adipokine levels. RASE1 suppressed adipogenic and lipid metabolism gene expression in mouse adipose and liver tissues and enhanced AMP-activated protein kinase levels in liver and adipose tissues and in serum adiponectin. RASE1 suppressed the NF-κB pathway and proinflammatory cytokines IL-10, IL-6, and TNF-α levels in mice which involve inflammation and progression of obesity. The overall results indicate RASE1 is a potential therapeutic formulation and functional food for treating or preventing obesity and inflammation.


Assuntos
Produtos Biológicos/uso terapêutico , Inflamação/tratamento farmacológico , Obesidade/tratamento farmacológico , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Inibidores da Angiogênese/uso terapêutico , Animais , Produtos Biológicos/administração & dosagem , Produtos Biológicos/toxicidade , Modelos Animais de Doenças , Diterpenos do Tipo Caurano/administração & dosagem , Composição de Medicamentos , Sinergismo Farmacológico , Feminino , Glucosídeos/administração & dosagem , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Lipólise/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Obesidade/genética , Obesidade/metabolismo , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/análogos & derivados , Fitoterapia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saponinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Stevia/química , Chá/química
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