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1.
Int J Biol Macromol ; 273(Pt 1): 133012, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38866296

RESUMO

The process of dissolving cellulose is a pivotal step in transforming it into functional, value-added materials, necessitating a thorough comprehension of the underlying mechanisms to refine its advanced processing. This article reviews cellulose dissolution using various solvent systems, along with an in-depth exploration of the associated dissolution mechanisms. The efficacy of different solvents, including aqueous solvents, organic solvents, ionic liquids, hybrid ionic liquid/cosolvent systems, and deep eutectic solvents, in dissolving cellulose is scrutinized, and their limitations and advantages are highlighted. In addition, this review methodically outlines the mechanisms at play within these various solvent systems and the factors influencing cellulose solubility. Conclusions drawn highlight the integral roles of the degree of polymerization, crystallinity, particle size, the type and sizes of cations and anions, alkyl chain length, ionic liquid/cosolvent ratio, viscosity, solvent acidity, basicity, and hydrophobic interactions in the dissolution process. This comprehensive review aims to provide valuable insights for researchers investigating biopolymer dissolution in a broader context, thereby paving the way for broader applications and innovations of these solvent systems.

2.
J Am Chem Soc ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869355

RESUMO

Coupling two magnetic anisotropic lanthanide ions via a direct covalent bond is an effective way to realize high magnetization blocking temperature of single-molecule magnets (SMMs) by suppressing quantum tunneling of magnetization (QTM), whereas so far only single-electron lanthanide-lanthanide bonds with relatively large bond distances are stabilized in which coupling between lanthanide and the single electron dominates over weak direct 4f-4f coupling. Herein, we report for the first time synthesis of short Dy(II)-Dy(II) single bond (3.61 Å) confined inside a carbon cage in the form of an endohedral metallofullerene Dy2@C82. Such a direct Dy(II)-Dy(II) covalent bond renders a strong Dy-Dy antiferromagnetic coupling that effectively quenches QTM at zero magnetic field, thus opening up magnetic hysteresis up to 25 K using a field sweep rate of 25 Oe/s, concomitant with a high 100 s magnetization blocking temperature (TB,100s) of 27.2 K.

3.
Comput Biol Med ; 177: 108646, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824788

RESUMO

Improved data sharing between healthcare providers can lead to a higher probability of accurate diagnosis, more effective treatments, and enhanced capabilities of healthcare organizations. One critical area of focus is brain tumor segmentation, a complex task due to the heterogeneous appearance, irregular shape, and variable location of tumors. Accurate segmentation is essential for proper diagnosis and effective treatment planning, yet current techniques often fall short due to these complexities. However, the sensitive nature of health data often prohibits its sharing. Moreover, the healthcare industry faces significant issues, including preserving the privacy of the model and instilling trust in the model. This paper proposes a framework to address these privacy and trust issues by introducing a mechanism for training the global model using federated learning and sharing the encrypted learned parameters via a permissioned blockchain. The blockchain-federated learning algorithm we designed aggregates gradients in the permissioned blockchain to decentralize the global model, while the introduced masking approach retains the privacy of the model parameters. Unlike traditional raw data sharing, this approach enables hospitals or medical research centers to contribute to a globally learned model, thereby enhancing the performance of the central model for all participating medical entities. As a result, the global model can learn about several specific diseases and benefit each contributor with new disease diagnosis tasks, leading to improved treatment options. The proposed algorithm ensures the quality of model data when aggregating the local model, using an asynchronous federated learning procedure to evaluate the shared model's quality. The experimental results demonstrate the efficacy of the proposed scheme for the critical and challenging task of brain tumor segmentation. Specifically, our method achieved a 1.99% improvement in Dice similarity coefficient for enhancing tumors and a 19.08% reduction in Hausdorff distance for whole tumors compared to the baseline methods, highlighting the significant advancement in segmentation performance and reliability.


Assuntos
Algoritmos , Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Blockchain , Aprendizado de Máquina , Privacidade , Imageamento por Ressonância Magnética/métodos
4.
Int J Biol Macromol ; 270(Pt 1): 132048, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704062

RESUMO

Polysaccharides are favourable and promising biopolymers for wound care applications due to their abundant natural availability, low cost and excellent biocompatibility. They possess different functional groups, such as carboxylic, hydroxyl and amino, and can easily be modified to obtain the desirable properties and various forms. This review systematically analyses the recent progress in polysaccharides derived materials for wound care applications, emphasizing the most commonly used cellulose, chitosan, alginate, starch, dextran and hyaluronic acid derived materials. The distinctive attributes of each polysaccharide derived wound care material are discussed in detail, along with their different forms, i.e., films, membranes, sponges, nanoemulsions, nanofibers, scaffolds, nanocomposites and hydrogels. The processing methods to develop polysaccharides derived wound care materials are also summarized. In the end, challenges related to polysaccharides derived materials in wound care management are listed, and suggestions are given to expand their utilization in the future to compete with conventional wound healing materials.


Assuntos
Materiais Biocompatíveis , Polissacarídeos , Cicatrização , Cicatrização/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/uso terapêutico , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Animais , Hidrogéis/química , Hidrogéis/uso terapêutico , Bandagens , Nanocompostos/química , Nanocompostos/uso terapêutico , Quitosana/química
5.
Eur J Pharm Sci ; 198: 106797, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38735401

RESUMO

The multicomponent etiology, complex clinical implications, dose-based side effect and degree of pain mitigation associated with the current pharmacological therapy is incapable in complete resolution of chronic neuropathic pain patients which necessitates the perpetual requirement of novel medication therapy. Therefore, this study explored the ameliorative aptitude of two novel methanimine imitative like (E)-N-(4-nitrobenzylidene)-4­chloro-2-iodobenzamine (KB 09) and (E)-N-(4-methylbenzylidene)-4­chloro-2-iodobenzamine (KB 10) in chronic constriction injury (CCI) of sciatic nerve induced neuropathic pain in rat model. Standard behavioral tests like dynamic and static allodynia, cold, thermal and mechanical hyperalgesia along with rotarod activity were performed at various experimental days like 0, 3, 7, 14 and 21. Enzyme linked immunosorbent assay (ELISA) on spinal tissue and antioxidant assays on sciatic nerve were executed accompanied by molecular docking and simulation studies. Prolonged ligation of sciatic nerve expressively induced hyperalgesia as well as allodynia in rats. KB 09 and KB 10 substantially attenuated the CCI elicited hyperalgesia and allodynia. They significantly reduced the biomarkers of pain and inflammation like Interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in ELISA and while enhanced the GSH, SOD and CAT and diminished the MDA levels during antioxidant assays. KB 09 displayed -9.62 kcal/mol with TNF-α and -7.68 kcal/mol binding energy with IL-6 whereas KB 10 exhibited binding energy of -8.20 kcal/mol with IL-6 while -11.68 kcal/mol with TNF-α and hence both trial compounds ensured stable interaction with IL-6 and TNF-α during computational analysis. The results advocated that both methanimine derivatives might be novel candidates for attenuation of CCI-induced neuropathic pain prospects via anti-nociceptive, anti-inflammatory and antioxidant mechanisms.


Assuntos
Hiperalgesia , Simulação de Acoplamento Molecular , Neuralgia , Nervo Isquiático , Animais , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Masculino , Hiperalgesia/tratamento farmacológico , Nervo Isquiático/lesões , Nervo Isquiático/efeitos dos fármacos , Ratos , Ratos Wistar , Modelos Animais de Doenças , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química , Antioxidantes/farmacologia , Antioxidantes/química , Simulação por Computador , Constrição , Iminas/química , Iminas/farmacologia
6.
Cureus ; 16(4): e58380, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38756297

RESUMO

Pharmacomechanical therapy and catheter-directed thrombolysis are potent treatments for venous thromboembolism. However, limited data exist regarding the management of thrombi in the inferior vena cava (IVC). IVC thrombus resulting from tumors is a particularly uncommon condition. Managing IVC tumor thrombi poses even greater challenges, as conventional therapies such as systemic anticoagulation and thrombolysis are often ineffective. In this report, we present the case of a 73-year-old male with an inferior vena cava tumor thrombus successfully managed through aspiration thrombectomy utilizing the Inari FlowTriever system.

7.
Sci Rep ; 14(1): 12195, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806561

RESUMO

High temperature stress influences plant growth, seed yield, and fatty acid contents by causing oxidative damage. This study investigated the potential of thiourea (TU) to mitigate oxidative stress and restoring seed oil content and quality in canola. The study thoroughly examined three main factors: (i) growth conditions-control and high temperature stress (35 °C); (ii) TU supplementation (1000 mg/L)-including variations like having no TU, water application at the seedling stage, TU application at seedling stage (BBCH Scale-39), water spray at anthesis stage, and TU application at anthesis stage (BBCH Scale-60); (iii) and two canola genotypes, 45S42 and Hiola-401, were studied separately. High temperature stress reduced growth and tissue water content, as plant height and relative water contents were decreased by 26 and 36% in 45S42 and 27 and 42% Hiola-401, respectively, resulting in a substantial decrease in seed yield per plant by 36 and 38% in 45S42 and Hiola-401. Seed oil content and quality parameters were also negatively affected by high temperature stress as seed oil content was reduced by 32 and 35% in 45S42 and Hiola-401. High-temperature stress increased the plant stress indicators like malondialdehyde, H2O2 content, and electrolyte leakage; these indicators were increased in both canola genotypes as compared to control. Interestingly, TU supplementation restored plant performance, enhancing height, relative water content, foliar chlorophyll (SPAD value), and seed yield per plant by 21, 15, 30, and 28% in 45S42; 19, 13, 26, and 21% in Hiola-401, respectively, under high temperature stress as compared to control. In addition, seed quality, seed oil content, linoleic acid, and linolenic acid were improved by 16, 14, and 22% in 45S42, and 16, 11, and 23% in Hiola-401, as compared to control. The most significant improvements in canola seed yield per plant were observed when TU was applied at the anthesis stage. Additionally, the research highlighted that canola genotype 45S42 responded better to TU applications and exhibited greater resilience against high temperature stress compared to genotype Hiola-401. This interesting study revealed that TU supplementation, particularly at the anthesis stage, improved high temperature stress tolerance, seed oil content, and fatty acid profile in two canola genotypes.


Assuntos
Antioxidantes , Brassica napus , Sementes , Tioureia , Brassica napus/genética , Brassica napus/efeitos dos fármacos , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Tioureia/farmacologia , Tioureia/análogos & derivados , Antioxidantes/metabolismo , Sementes/efeitos dos fármacos , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Temperatura Alta , Estresse Oxidativo/efeitos dos fármacos , Genótipo , Resposta ao Choque Térmico/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/metabolismo
8.
ACS Omega ; 9(20): 22123-22135, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799342

RESUMO

Autoimmune disorders include vast and distinct illnesses and are characterized by an immune system-mediated attack on the body's own tissues. Because of their ability to impact any portion of the body, their clinical symptoms are incredibly varied. The variations in symptoms are normally linked with the release and activation of vasoactive, chemotactic substances and cytokines. Cytokines perform a multitude of vital biological tasks, such as immune response control, inflammation, proliferation, and tissue repair. The reversal of inflammatory cytokines and leukocyte infiltration into the inflamed tissue by natural compounds provides an effective remedy for autoimmune diseases. Here, the oral administration of trans-chalcone (TC) for 28 days was tested with gradually increasing doses (30, 60, and 120 mg/kg) in complete Freund's adjuvant (CFA)-provoked joint tissue stiffness in rats. Paw edema, arthritic index, joint stiffness, thermal and flexion pain, C-reactive protein, and rheumatoid factor (RF) levels were determined to check the tested drug effectiveness in a chronic inflammatory model. Molecular docking studies revealed strong binding affinity with inflammatory cytokines and mediators such as TNF-α, IL-17, COX-2, and iNOS; further, they were quantified at the mRNA level by RT-PCR and ELISA analysis. Oral administration of TC significantly ameliorated paw edema, thymus and spleen indices, joint stiffness, thermal and flexion pain, C-reactive protein, RF, mobility, and stance of the treated animals. This therapeutic effectiveness was linked with a reduction in the mRNA expression of proinflammatory cytokines such as IL-1ß, IL-6, and IL-17. The findings of the reported research confirmed the effectiveness of TC in ameliorating joint stiffness and flexion pain by prominently lowering the inflammatory cytokines.

9.
AoB Plants ; 16(2): plae018, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38601216

RESUMO

Humic acids have been widely used for centuries to enhance plant growth and productivity. The beneficial effects of humic acids have been attributed to different functional groups and phytohormone-like compounds enclosed in macrostructure. However, the mechanisms underlying the plant growth-promoting effects of humic acids are only partially understood. We hypothesize that the bio-stimulatory effect of humic acids is mainly due to the modulation of innate pathways of auxin and cytokinin biosynthesis in treated plants. A physiological investigation along with molecular characterization was carried out to understand the mechanism of bio-stimulatory effects of humic acid. A gene expression analysis was performed for the genes involved in auxin and cytokinin biosynthesis pathways in wheat seedlings. Furthermore, Arabidopsis thaliana transgenic lines generated by fusing the auxin-responsive DR5 and cytokinin-responsive ARR5 promoter to ß-glucuronidase (GUS) reporter were used to study the GUS expression analysis in humic acid treated seedlings. This study demonstrates that humic acid treatment improved the shoot and root growth of wheat seedlings. The expression of several genes involved in auxin (Tryptophan Aminotransferase of Arabidopsis and Gretchen Hagen 3.2) and cytokinin (Lonely Guy3) biosynthesis pathways were up-regulated in humic acid-treated seedlings compared to the control. Furthermore, GUS expression analysis showed that bioactive compounds of humic acid stimulate endogenous auxin and cytokinin-like activities. This study is the first report in which using ARR5:GUS lines we demonstrate the biostimulants activity of humic acid.

10.
Cureus ; 16(3): e57110, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38686255

RESUMO

Background Typhoid fever presents a significant challenge in developing nations, exacerbated by the emergence of antibiotic-resistant strains due to widespread prevalence and overuse of antibiotics. This study seeks to assess the antibiogram profiles of Salmonella species isolated from blood cultures of patients hospitalized at two prominent tertiary care hospitals in Peshawar, Pakistan: Khyber Teaching Hospital (KTH) and Hayatabad Medical Complex (HMC). By examining these profiles, the research aims to provide valuable insights into the evolving landscape of antibiotic resistance in the context of typhoid fever management. Materials and Methods This retrospective cross-sectional study utilized data gathered from two hospitals in Peshawar, KTH and HMC. Cases of enteric fever were identified based on positive blood cultures for Salmonella species. The study encompasses demographic information, seasonal prevalence, and antibiogram profiles of 3,137 cases that were presented between 2017 and 2023. Results Among the total 3,137 cases, males accounted for the majority, comprising 63% (2,044 cases). Particularly notable was the clustering of cases among children and adolescents aged one to 24 years. The incidence peaked during the months of summer and spring, from April to September. In terms of Salmonella Typhi isolates, considerable resistance was noted against first-line antibiotics such as amoxicillin/clavulanate (80.1%), co-trimoxazole/trimethoprim-sulfamethoxazole (66.6%), and chloramphenicol (86.9%), as well as against ceftriaxone (79.7%) and ciprofloxacin (51.6%). Conversely, certain antibiotics displayed higher sensitivity patterns, including meropenem (97.8%), doripenem (99.5%), imipenem (97.7%), ertapenem (96.5%), polymyxin B (99.4%), colistin (98.1%), and tigecycline (97.3%). Despite a limited sample size of 214 specimens, fosfomycin demonstrated a remarkable sensitivity of 93.4%. Sensitivities of amikacin and gentamicin were 90.7% and 81.5%, respectively. However, the sensitivity of azithromycin was concerning, standing at 66.5%. The antibiogram pattern for Salmonella exhibited significant and drastic changes. Conclusion In conclusion, this study sheds light on a higher prevalence of typhoid fever among males, with a notable seasonal peak observed during the summer and spring months. The age group most affected spans from one to 24 years. Salmonella isolates displayed significant resistance to conventional first-line antibiotics, alongside ciprofloxacin and third-generation cephalosporins. Azithromycin exhibited lower sensitivity compared to amikacin, gentamicin, and fosfomycin. The research advocates for the empirical use of amikacin, gentamicin, fosfomycin, and meropenem in the treatment of typhoid fever in Pakistan. Urgent measures, including regular Salmonella antibiogram surveillance, antibiotic stewardship, public health education, and Salmonella vaccination programs, are deemed crucial for primary disease prevention.

11.
Biomed Pharmacother ; 174: 116544, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599058

RESUMO

The current study was designed to investigate the potential of a synthetic therapeutic agent for better management of pain and inflammation, exhibiting minimal to non-existent ulcerogenic effects. The effect of 1-(2-chlorobenzoyl)-3-(2,3-dichlorophenyl) thiourea was assessed through model systems of nociception and anti-inflammatory activities in mice. In addition, the ulcerogenic potential was evaluated in rats using the NSAID-induced pyloric ligation model, followed by histopathological and biochemical analysis. The test was conducted on eight groups of albino rats, comprising of group I (normal saline), groups II and III (aspirin® at doses of 100 mg/kg and 150 mg/kg, respectively), groups IV and V (indomethacin at doses of 100 mg/kg and 150 mg/kg, respectively), and groups VI, VII, and VIII (lead-compound at 15 mg/kg, 30 mg/kg and 45 mg/kg doses, respectively). Furthermore, molecular docking analyses were performed to predict potential molecular target site interactions. The results showed that the lead-compound, administered at doses of 15, 30, and 45 mg/kg, yielded significant reductions in chemically and thermally induced nociceptive pain, aligning with the levels observed for aspirin® and tramadol. The compound also effectively suppressed inflammatory response in the carrageenan-induced paw edema model. As for the ulcerogenic effects, the compound groups displayed no considerable alterations compared to the aspirin® and indomethacin groups, which displayed substantial increases in ulcer scores, total acidity, free acidity, and gastric juice volume, and a decrease in gastric juice pH. In conclusion, these findings suggest that our test compound exhibits potent antinociceptive, anti-inflammatory properties and is devoid of ulcerogenic effects.


Assuntos
Inflamação , Simulação de Acoplamento Molecular , Nociceptividade , Úlcera Gástrica , Tioureia , Animais , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Úlcera Gástrica/tratamento farmacológico , Tioureia/análogos & derivados , Tioureia/farmacologia , Masculino , Nociceptividade/efeitos dos fármacos , Camundongos , Inflamação/tratamento farmacológico , Inflamação/patologia , Ratos , Ratos Wistar , Analgésicos/farmacologia , Analgésicos/química , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Simulação por Computador , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Mucosa Gástrica/metabolismo , Indometacina/farmacologia , Dor/tratamento farmacológico , Dor/induzido quimicamente , Dor/patologia , Anti-Inflamatórios/farmacologia
12.
Plant Physiol ; 195(2): 1660-1680, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38445796

RESUMO

Low-temperature sensitivity at the germination stage is a challenge for direct seeding of rice in Asian countries. How Ca2+ and auxin (IAA) signaling regulate primary root growth under chilling remains unexplored. Here, we showed that OsCML16 interacted specifically with OsPILS7a to improve primary root elongation of early rice seedlings under chilling. OsCML16, a subgroup 6c member of the OsCML family, interacted with multiple cytosolic loop regions of OsPILS7a in a Ca2+-dependent manner. OsPILS7a localized to the endoplasmic reticulum membranes and functioned as an auxin efflux carrier in a yeast growth assay. Transgenics showed that presence of OsCML16 enhanced primary root elongation under chilling, whereas the ospils7a knockout mutant lines showed the opposite phenotype. Moreover, under chilling conditions, OsCML16 and OsPILS7a-mediated Ca2+ and IAA signaling and regulated the transcription of IAA signaling-associated genes (OsIAA11, OsIAA23, and OsARF16) and cell division marker genes (OsRAN1, OsRAN2, and OsLTG1) in primary roots. These results show that OsCML16 and OsPILS7a cooperatively regulate primary root elongation of early rice seedlings under chilling. These findings enhance our understanding of the crosstalk between Ca2+ and IAA signaling and reveal insights into the mechanisms underlying cold-stress response during rice germination.


Assuntos
Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Oryza , Proteínas de Plantas , Raízes de Plantas , Plântula , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Calmodulina/metabolismo , Calmodulina/genética , Cálcio/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais
13.
Heliyon ; 10(4): e26149, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384569

RESUMO

Biomedical image analysis plays a crucial role in enabling high-performing imaging and various clinical applications. For the proper diagnosis of blood diseases related to red blood cells, red blood cells must be accurately identified and categorized. Manual analysis is time-consuming and prone to mistakes. Analyzing multi-label samples, which contain clusters of cells, is challenging due to difficulties in separating individual cells, such as touching or overlapping cells. High-performance biomedical imaging and several medical applications are made possible by advanced biosensors. We develop an intelligent neural network model that can automatically identify and categorize red blood cells from microscopic medical images using region-based convolutional neural networks (RCNN) and cutting-edge biosensors. Our model successfully navigates obstacles like touching or overlapping cells and accurately recognizes various blood structures. Additionally, we utilized data augmentation as a pre-processing method on microscopic images to enhance the model's computational efficiency and expand the sample size. To refine the data and eliminate noise from the dataset, we utilized the Radial Gradient Index filtering algorithm for imaging data equalization. We exhibit improved detection accuracy and a reduced model loss rate when using medical imagery datasets to apply our proposed model in comparison to existing ResNet and GoogleNet models. Our model precisely detected red blood cells in a collection of medical images with 99% training accuracy and 91.21% testing accuracy. Our proposed model outperformed earlier models like ResNet-50 and GoogleNet by 10-15%. Our results demonstrated that Artificial intelligence (AI)-assisted automated red blood cell detection has the potential to revolutionize and speed up blood cell analysis, minimizing human error and enabling early illness diagnosis.

14.
Int J Biol Macromol ; 261(Pt 2): 129764, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296144

RESUMO

In this study, Hydroxyapatite nanoparticles (HANPs), derived from eggshell waste, were employed to reinforce chitosan biopolymer-based films through the solvent-casting method. The impact of varying HANPs content (1%, 3%, 5%, and 10 wt %) in bionanocomposites was investigated. The influence of HANPs addition on the final film properties was comprehensively analyzed using Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA), mechanical (tensile) testing, and Water Vapor Permeability (WVP). The morphological aspects of bionanocomposites and the dispersion of nanoparticles within the matrix were studied using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). The structural changes in the films were probed using Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) techniques. Results indicated that the addition of 1% and 3% of HANPs exhibited a higher glass transition temperature and improved thermal stability in bionanocomposites. Films with 3% HANPs content exhibited a notable increase in tensile strength, showing a 61.54% increase, while films with 1% HANPs content displayed a 52% reduction in WVP compared to pristine chitosan films. These findings underscore the significant potential of chitosan-hydroxyapatite bionanocomposite films for applications in food packaging applications.


Assuntos
Quitosana , Nanopartículas , Animais , Quitosana/química , Durapatita , Casca de Ovo , Resistência à Tração , Nanopartículas/química
15.
Heliyon ; 9(11): e22483, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38074891

RESUMO

Neurodegenerative complications, like Alzheimer's disease (AD) exert adverse effects i.e. psychological and physiological in the central nervous system. The synthetic drugs used for these complications have negative effects on body health and therefore natural remedies are a good and targeted approach to counter such complications. Alternatively, fruits and a variety of biochemicals which are an important source of diet, can be used for remedial purposes. Due to the antioxidant properties of polyphenolic compounds, several companies utilize this property to advertise polyphenol-rich beverages. Pomegranate (Punica granatum L.), is one such fruit that is well known for its medical usage due to its antioxidant properties. In the cuurent study a literature search survey was performed on traditional uses, phytochemicals on pomegranate and their medical applications especaily in neurodegenerative deasese using electronic data bases like PubMed, Google Scholar, Scopus, Science Direct Wikipedia and Springer Nature. Based on previous preclinical and clinical studies, pomegranate juice, extracts, and its bioactive constituents have shown many mitigating properties, including suppression of inflammatory cell signaling, reduction in expression of genes associated with oxidative stress as well as pro-inflammatory cytokines in neurons, decreased production of inflammatory and oxidative stress biomarkers and increased expression of endothelial nitric oxide synthase. It also decreases the expression of soluble amyloid protein procurer ß (sAPPß), ß-secretase and carboxyl terminal fragment ß (CTFß). Similarly, during an in-vivo study on APP/PS1 mice, pomegranate supplementation has been shown to impart cognitive aid by the protection of neurons and triggering neurogenesis through anti-inflammatory signaling pathway. In conclusion, pomegranate supplementation can be a promising source of protection against Alzheimer's disease.

16.
J Ethnobiol Ethnomed ; 19(1): 62, 2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38105177

RESUMO

BACKGROUND: In multicultural societies, traditional knowledge among minorities faces several challenges. Minority groups often face difficult situations living in specific peripheral geographies and striving to retain their biocultural heritage, including medicinal plant knowledge and practices. Folk medicinal plant knowledge is a dynamic eco-cultural complex influenced by various environmental, socio-cultural, and political factors. Examining medicinal plant knowledge among minorities has been an increasingly popular topic in cross-cultural ethnobiology. It also helps understand the dynamics of local/traditional ecological knowledge (LEK/TEK) change within a given community. The current study was designed to investigate the status of medicinal plant knowledge among two linguistic groups, i.e. Ormurs and Pathans, living in a remote valley of West Pakistan. METHODS: We recruited 70 male study participants from the studied groups for semi-structured interviews to record the medicinal plant use of their communities. Data were compared among the two studied communities using the stacked charts employing the presence or absence of data with Past 4.03 and Venn diagrams. Use reports (URs) were counted for each recorded taxon. RESULTS AND DISCUSSION: A total of seventy-four medicinal plants were quoted as used as ethnomedicines by the researched communities. Most of the reported plants were used to treat digestive and liver problems. The cross-cultural comparison revealed a considerable homogeneity of medicinal plant knowledge (the two groups commonly used more than seventy plants); however, comparing uses recorded for the widely utilised medicinal plants showed numerous idiosyncratic uses among Ormurs but very few among Pathans. Ormurs reported a higher number of cultivated, wild, and imported plant uses than did Pathans. These results indicate that, compared to Pathans, the Ormur linguistic minority retain more folk medicinal plant knowledge, which may be explained by the fact that they have incorporated different folk remedies: their "own knowledge" plus that of Pathans, with whom they have lived together for centuries. Moreover, the local plant nomenclature among Ormurs was highly affected by the plant nomenclature of Pathans. CONCLUSION: The current study revealed that living together for a few centuries has not implied sharing plant knowledge (as the Pathans do not seem to have learnt from the Ormurs) or, in other words, that plant knowledge exchanges have been unidirectional. The findings show that the Pashto dominant culture may have possibly put pressure on the minority groups and affected local plant-centred cultural practices, as we see in the case of local plant nomenclature hybridisation among Omuri speakers. Hence, it is imperative to employ diverse educational strategies to revitalise the decline of medicinal plant knowledge in the studied communities, especially among Ormurs, who need more attention as they face more challenges than the other group. Locally based strategies should be devised to restore the fading connection with nature, which will be advantageous for revitalising plant knowledge.


Assuntos
Plantas Medicinais , Humanos , Etnobotânica , Paquistão , Medicina Tradicional/métodos , Fitoterapia
17.
Neurotoxicology ; 99: 274-281, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37939858

RESUMO

Ethanol administration triggers an inflammatory response that leads to a complex series of immune responses including the release of an excessive amount of inflammatory mediators particularly tumor necrosis factor (TNF-α) and nuclear factor-kB (NF-KB) which produce a large amount of reactive oxygen species. The inflammatory-induced cytotoxicity is increased when the PI3-kinase/Akt pathway is inhibited. Some studies have also shown that ethanol suppresses the PI3-kinase signaling pathway induced by receptor activation. Friedelin and Glutinol belong to pentacyclic triterpenoid class and are known for their anti-inflammatory and antioxidant properties. The present study was aimed to elucidate the effects of these phytoconstituents on one of the key ethanol-induced neuronal damage pathways. The pups having (5-7 g average body weight) were used and randomly divided into groups. The control and ethanol treated pups were administered 0.9% normal saline while treated pups received glutinol and friedelin (30 mg/kg subcutaneously) respectively. After four hours all the experimental animals were sacrificed and their brains were collected carefully for protein expression analysis of p-Akt, TNF-α, NF-KB, caspase-3 and PARP-1 employing immunoblotting technique. Hemolytic, DNA protection, chelating power and ß-carotene assays results revealed that freidelin and glutinol are safe for parenteral administration. Glutinol administration with ethanol significantly abridged the ethanol induced over expression of TNF-α, caspase-3 and PARP-1 in pup's brain. Similarly, freidelin attenuated the neurodegeneration by inhibiting the ethanol induced p-JNK and NF-kB expression in pups' brain. This protection may be attributed to the revival of p-Akt signaling for cell survival. It is concluded that the present study demonstrates the neuro-protective effects of friedelin and glutinol via modulating the capase-3 and PARP-1 expression and modulating the neuronal apoptotic pathways.


Assuntos
Lupanos , NF-kappa B , Neuroproteção , Fator de Necrose Tumoral alfa , Animais , Encéfalo , Caspase 3/metabolismo , Etanol/toxicidade , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Lupanos/farmacologia
18.
Carbohydr Polym ; 321: 121318, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739510

RESUMO

The attention to polymer-based biomaterials, for instance, chitosan and its derivatives, as well as the techniques for using them in numerous scientific domains, is continuously rising. Chitosan is a decomposable naturally occurring polymeric material that is mostly obtained from seafood waste. Because of its special ecofriendly, biocompatible, non- toxic nature as well as antimicrobial properties, chitosan-based materials have received a lot of interest in the field of biomedical applications. The reactivity of chitosan is mainly because of the amino and hydroxyl groups in its composition, which makes it further fascinating for various uses, including biosensing, textile finishing, antimicrobial wound dressing, tissue engineering, bioimaging, gene, DNA and drug delivery and as a coating material for medical implants. This study is an overview of the different types of chitosan-based materials which now a days have been fabricated by applying different techniques and modifications that include etherification, esterification, crosslinking, graft copolymerization and o-acetylation etc. for hydroxyl groups' processes and acetylation, quaternization, Schiff's base reaction, and grafting for amino groups' reactions. Furthermore, this overview summarizes the literature from recent years related to the important applications of chitosan-based materials (i.e., thin films, nanocomposites or nanoparticles, sponges and hydrogels) in different biomedical applications.


Assuntos
Quitosana , Esterificação , Materiais Biocompatíveis/farmacologia , Acetilação , Bandagens , Polímeros
19.
Biomolecules ; 13(8)2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37627324

RESUMO

Calcium (Ca2+) sparks are the elementary events of excitation-contraction coupling, yet they are not explicitly represented in human ventricular myocyte models. A stochastic ventricular cardiomyocyte human model that adapts to intracellular Ca2+ ([Ca2+]i) dynamics, spark regulation, and frequency-dependent changes in the form of locally controlled Ca2+ release was developed. The 20,000 CRUs in this model are composed of 9 individual LCCs and 49 RyRs that function as couplons. The simulated action potential duration at 1 Hz steady-state pacing is ~0.280 s similar to human ventricular cell recordings. Rate-dependence experiments reveal that APD shortening mechanisms are largely contributed by the L-type calcium channel inactivation, RyR open fraction, and [Ca2+]myo concentrations. The dynamic slow-rapid-slow pacing protocol shows that RyR open probability during high pacing frequency (2.5 Hz) switches to an adapted "nonconducting" form of Ca2+-dependent transition state. The predicted force was also observed to be increased in high pacing, but the SR Ca2+ fractional release was lower due to the smaller difference between diastolic and systolic [Ca2+]SR. Restitution analysis through the S1S2 protocol and increased LCC Ca2+-dependent activation rate show that the duration of LCC opening helps modulate its effects on the APD restitution at different diastolic intervals. Ultimately, a longer duration of calcium sparks was observed in relation to the SR Ca2+ loading at high pacing rates. Overall, this study demonstrates the spontaneous Ca2+ release events and ion channel responses throughout various stimuli.


Assuntos
Artrogripose , Sinalização do Cálcio , Humanos , Miócitos Cardíacos , Potenciais de Ação , Ventrículos do Coração
20.
Sci Rep ; 13(1): 13006, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563284

RESUMO

The high-precision machine tool's dynamic, static, and rigid nature directly affects the machining efficiency and surface quality. Static and dynamic analyses are essential for the design and improvement of precision machine to ensure good tool performance under difficult and demanding machining conditions. In this study, the performance of a high-precision machine tool was analyzed using its virtual model created using CAD. Static and model analysis using ANSYS Workbench software was conducted to establish the tool's static deformation and static stiffness. Furthermore, the static and dynamic characteristics of the tool were explored using a finite element modeling approach to study their performance. In particular, the structure, static force, modal, frequency spectrum, and topology optimization of machine tools were primarily analyzed. Using model analysis, we found the first four different frequencies (22.5, 28.9, 40.6, and 47.4 Hz) and vibration type, which suggested of a weak link. Further static structural analysis revealed that the deformation of the spindle was 67.26 µm. An experimental static rigidity analysis was performed, and the experimental deformation values of the tool and spindle were obtained. The static and dynamic characteristics, as well as the accuracy and efficiency of the finite element model, were verified by comparing the data with the finite element analysis (FEA) results. Subsequently, we modified the settings and analysis model to ensure that the analysis results were consistent with the experimental findings. The error between the two results was within 1.56%. For an applied load of 5000 N on the spindle nose, the tool nose transient response was 0.5 s based on transient analysis. Under the condition that the structural deformation is as constant as possible, the lightweight structure may achieve the minimum weight and enhance the natural frequency; thus, the ideal structure will be obtained, and finite element analysis will then be performed. The optimal conditions for topology optimization include a lightweight structure, reduced structural deformation, and increased natural frequency of the structure. The developed method improves structural optimization, increases the ability of the product to be manufactured, and offers designers a variety of price-effective options.

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