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1.
Sci Adv ; 10(16): eadm8815, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38630817

RESUMO

Organisms surveil and respond to their environment using behaviors entrained by metabolic cues that reflect food availability. Mitochondria act as metabolic hubs and at the center of mitochondrial energy production is the protonmotive force (PMF), an electrochemical gradient generated by metabolite consumption. The PMF serves as a central integrator of mitochondrial status, but its role in governing metabolic signaling is poorly understood. We used optogenetics to dissipate the PMF in Caenorhabditis elegans tissues to test its role in food-related behaviors. Our data demonstrate that PMF reduction in the intestine is sufficient to initiate locomotor responses to acute food deprivation. This behavioral adaptation requires the cellular energy regulator AMP-activated protein kinase (AMPK) in neurons, not in the intestine, and relies on mitochondrial dynamics and axonal trafficking. Our results highlight a role for intestinal PMF as an internal metabolic cue, and we identify a bottom-up signaling axis through which changes in the PMF trigger AMPK activity in neurons to promote foraging behavior.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Mitocôndrias/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Transdução de Sinais
2.
BMC Complement Med Ther ; 24(1): 65, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291462

RESUMO

BACKGROUND: Type 2 Diabetes mellitus (DM) is an affliction impacting the quality of life of millions of people worldwide. An approach used in the management of Type 2 DM involves the use of the carbohydrate-hydrolyzing enzyme inhibitor, acarbose. Although acarbose has long been the go-to drug in this key approach, it has become apparent that its side effects negatively impact patient adherence and subsequently, therapeutic outcomes. Similar to acarbose in its mechanism of action, bee propolis, a unique natural adhesive biomass consisting of biologically active metabolites, has been found to have antidiabetic potential through its inhibition of α-amylase. To minimize the need for ultimately novel agents while simultaneously aiming to decrease the side effects of acarbose and enhance its efficacy, combination drug therapy has become a promising pharmacotherapeutic strategy and a focal point of this study. METHODS: Computer-aided molecular docking and molecular dynamics (MD) simulations accompanied by in vitro testing were used to mine novel, pharmacologically active chemical entities from Egyptian propolis to combat Type 2 DM. Glide docking was utilized for a structure-based virtual screening of the largest in-house library of Egyptian propolis metabolites gathered from literature, in addition to GC-MS analysis of the propolis sample under investigation. Thereafter, combination analysis by means of fixed-ratio combinations of acarbose with propolis and the top chosen propolis-derived phytoligand was implemented. RESULTS: Aucubin, identified for the first time in propolis worldwide and kaempferol were the most promising virtual hits. Subsequent in vitro α-amylase inhibitory assay demonstrated the ability of these hits to significantly inhibit the enzyme in a dose-dependent manner with an IC50 of 2.37 ± 0.02 mM and 4.84 ± 0.14 mM, respectively. The binary combination of acarbose with each of propolis and kaempferol displayed maximal synergy at lower effect levels. Molecular docking and MD simulations revealed a cooperative binding mode between kaempferol and acarbose within the active site. CONCLUSION: The suggested strategy seems imperative to ensure a steady supply of new therapeutic entities sourced from Egyptian propolis to regress the development of DM. Further pharmacological in vivo investigations are required to confirm the potent antidiabetic potential of the studied combination.


Assuntos
Diabetes Mellitus Tipo 2 , Própole , Humanos , Acarbose/farmacologia , Acarbose/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Quempferóis , Própole/farmacologia , Simulação de Acoplamento Molecular , Diabetes Mellitus Tipo 2/tratamento farmacológico , Egito , Qualidade de Vida , alfa-Glucosidases/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , alfa-Amilases/metabolismo
3.
BMC Oral Health ; 23(1): 967, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053146

RESUMO

BACKGROUND: In-vitro data from a clinically well-known lithium disilicate ceramic reference was used to assess the expected performance of resin-based materials in implant dentistry. The purpose of the study was to compare the bond strength and marginal adaptation of nano-ceramic hybrid composite crowns cemented to stock cement-retained abutments to lithium disilicate crowns. METHODS: Twenty abutment analogs were embedded into auto-polymerizing acrylic resin blocks. The blocks were divided into 2 groups according to the restorative crown material. The 2 groups were divided as follows: Resin nano-ceramic group and lithium disilicate group. Abutment analogs in both groups were scanned using a laboratory scanner, and the restorations were designed, manufactured, and cemented with resin cement over the corresponding group. All samples were tested for marginal adaptation and bond strength after storage for 24 hours at 37 °C in 100% humidity. Data were collected, tabulated, and statistically analysed using the appropriate tests. Normality was checked using Shapiro Wilk test and Q-Q plots. Data were normally distributed. Variables were presented using mean, 95% Confidence Interval (CI) and standard deviation in addition to median and Inter Quartile Range (IQR). Differences between groups regarding debonding forces was assessed using independent t test. Two Way ANOVA was performed to assess the effect of material and bonding on marginal gap. All tests were two tailed and p value was set at < 0.05. RESULTS: Marginal gap and debonding force values were significantly different according to the type of material used (P < .05). Resin nano-ceramic crowns presented lower marginal gap values before (20.80 ± 8.87 µm) and after (52.11 ± 22.92 µm) bonding than lithium disilicate crowns. The debonding force value for resin nano-ceramic crowns (284.30 ± 26.44 N) was significantly higher than that for lithium disilicate crowns (253.30 ± 33.26 N). Adhesive failure mode was detected in all the specimens in both groups. CONCLUSIONS: The type of material used for implant-supported cement-retained crowns had a statistically significant effect on marginal adaptation and bond strength. Resin nano-ceramic implant-supported cement-retained crowns had better marginal adaptation and higher bond strength than those manufactured using lithium disilicate.


Assuntos
Coroas , Cimentos Dentários , Humanos , Cimentos de Ionômeros de Vidro , Materiais Dentários , Cerâmica , Cimentos de Resina , Desenho Assistido por Computador , Teste de Materiais
4.
PLoS One ; 18(11): e0294411, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37967069

RESUMO

A heterogeneous network (HetNet), combining different technologies, is considered a promising solution adopted by several upcoming generations of mobile networks to keep up with the rapid development of mobile users' requirements while improving network performance. In this scenario, a vertical handover (VHO) algorithm is responsible for ensuring the continuity of the ongoing user connection while moving within the coverage of the HetNet. Although various VHO algorithms were proposed, achieving efficient performance from both network and user perspectives remains challenging. This paper proposes an adaptive optimized vertical handover algorithm based on a multi-attribute decision-making (MADM) algorithm integrated with particle swarm optimization and gravitational search algorithm (PSOGSA) as a framework to implement the handover process. The algorithm includes three main ideas. Firstly, a network selection framework is proposed considering the most important criteria, including signal strength and other networks' attributes, along with users' characteristics regarding their mobility and service preferences. Secondly, two new parameters are introduced as control handover parameters named load factor (LF) and score priority (SP) to reduce unnecessary handovers and the overall HetNet power consumption while achieving balanced load distribution. Lastly, the desired aims are formulated as an objective function, then the PSOGSA algorithm is used to reach the optimal values of both LF and SP, which will be considered when executing the handover algorithm. The presented algorithm is simulated in a heterogeneous wireless network where the fifth-generation (5G) wireless technology coexists with other radio access networks to improve the evaluation field of the proposed algorithm. Also, the proposed algorithm's performance is evaluated in the case of using various MADM algorithms. The simulation results show that the proposed adaptive optimized approach attains efficient performance by decreasing unnecessary handovers by more than 40% and achieving much better load distribution by around 20% to 40%, outperforming traditional handover approaches.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Simulação por Computador , Tecnologia sem Fio , Gravitação
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123063, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37390719

RESUMO

The target of the current study is to create a novel hybrid nanocomposite (Cs@Pyc.SOF) by combining the anti-hepatitis C virus (HCV) drug sofosbuvir with the nano antioxidant pycnogenol (Pyc) and nano biomolecules like chitosan nanoparticles (Cs NPs). The characterization procedure works to verify the creation of nanocomposite (NCP) using several different techniques. UV-Vis spectroscopy is used to measure SOF loading efficiency. The various concentrations of the SOF drug were used to determine the binding constant rate Kb, which was found to be 7.35 ± 0.95 min-1 with an 83% loading efficiency. At pH 7.4, the release rate was 80.6% after two hours and 92% after 48 h, whereas at pH 6.8, it was 29% after two hours and 94% after 48 h. After 2 and 48 h, the release rate in water was 38% and 77%, respectively. . The SRB technique for fast screening is used for the cytotoxicity test, where the investigated composites show a safety status and high viability against the examined cell line. The cytotoxicity assay of the SOF hybrid materials has been identified with cell lines like mouse normal liver cells (BNL). So, Cs@Pyc.SOF was recommended as a substitute medication for the therapy of HCV, but the results need clinical studies.


Assuntos
Quitosana , Hepatite C , Animais , Camundongos , Sofosbuvir , Antivirais/uso terapêutico , Hepacivirus , Preparações Farmacêuticas , Quimioterapia Combinada , Hepatite C/tratamento farmacológico , Análise Espectral , Ribavirina
6.
Cell Biochem Funct ; 41(6): 642-657, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37342005

RESUMO

The hepatoprotective effects of methanol extract of Mimusops elengi Linn. (M. elengi L.) leaves and isolated pure myricitrin (3-, 4-, 5-, 5, 7-five hydroxyflavone-3-O-α-l-rhamnoside) (Myr) were evaluated in male rats exposed to γ-irradiation. The extraction of M. elengi L. leaves was performed using ethyl acetate (EtOAC). Seven groups of rats were used: control group, irradiated (IRR) group (6 Gy of γ-rays in a single dose), vehicle group (oral administration of 0.5% carboxymethyl cellulose for 10 days), EtOAC extract group (100 mg/kg body weight of extract, orally for 10 days), EtOAC + IRR group (administration of extract and exposure to γ-rays on Day 7), Myr group (50 mg/kg body weight Myr, orally for 10 days), and Myr + IRR group (administration of Myr and exposure to γ-rays on Day 7). High-performance liquid chromatography and 1H-nuclear magnetic resonance were used to isolate and characterize the compounds from M. elengi L. leaves. Enzyme-linked immunosorbent assay was used for biochemical analyses. Identified compounds were Myr, myricetin 3-O-galactoside, myricetin 3-O-rahmnopyranoside (1 → 6) glucopyranoside, quercetin, quercitol, gallic acid, α-,ß-amyrin, ursolic acid, and lupeol. Serum aspartate transaminase and alanine transaminase activities were significantly increased, while serum protein and albumin levels were significantly decreased after irradiation. Hepatic levels of tumor necrosis factor-α, prostaglandin 2, inducible nitric oxide synthase, interleukin-6 (IL-6), and IL-12 were increased following irradiation. Improvements were observed in most serological parameters after treatment with extract or pure Myr, with histological analyses confirming decreased liver injury in treated rats. Our study demonstrates that pure Myr has a greater hepatoprotective effect than M. elengi leaf extracts against irradiation-induced hepatic inflammation.


Assuntos
Mimusops , Extratos Vegetais , Ratos , Masculino , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Mimusops/química , Fígado , Peso Corporal , Folhas de Planta
7.
Cellulose (Lond) ; 30(6): 3505-3522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36994234

RESUMO

In this work, new chitosan derivative nanofibers that exhibit antibacterial properties were successfully fabricated. The two CS Schiff base derivatives (CS-APC and CS-2APC) were prepared by incorporating 4-amino antipyrine moiety in two different ratios, followed by a reductive amination to obtain the corresponding derivatives CS-APCR and CS-2APCR. Spectral analyses were used to confirm the chemical structure. The molecular docking evaluation of CS-APC, CS-APCR, and CS was conducted on DNA topoisomerase IV, thymidylate kinase and SARS-CoV-2 main protease (3CLpro) active sites. CS-APCR showed a well-fitting into the three enzyme active sites with docking score values of - 32.76, - 35.43 and - 30.12 kcal/mol, respectively. The nanocomposites of CS derivatives were obtained by electrospinning the blends of CS-2APC and CS-2APCR with polyvinyl pyrrolidone (PVP) at 20 kV. The morphology of the nanofibers was investigated by scanning electron microscopy (SEM). It was found that fiber diameters were significantly decreased when CS-2APC and CS-2APCR were incorporated into pure PVP to reach 206-296 nm and 146-170 nm, respectively, compared to 224-332 nm for pure PVP. The derivatives of CS and their nanofibers with PVP were found to have antibacterial activities against two strains of Staphylococcus aureus and Escherichia coli. Data revealed that CS-2APC nanofibers showed antibacterial activity to the two strains of E. coli less than CS-2APCR nanofibers.

8.
J Cardiothorac Surg ; 17(1): 80, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35443734

RESUMO

OBJECTIVE: Many studies still dispute the identification of independent risk factors that influence outcome after neonatal cardiac surgery. We present our study to announce the contemporary outcomes and risk profile of neonatal cardiac surgery at our institute. METHODS: We designed a retrospective study of neonatal patients who underwent surgery for congenital heart diseases between June 2011 and April 2020. Demographic, operative, and postoperative data were collected from medical records and surgical databases. The primary outcome was the operative mortality (in-hospital death) and secondary outcomes included hospital length of stay, intensive care unit stay, duration of mechanical ventilation. RESULTS: In total, 1155 cardiac surgeries in children were identified; of these, 136 (11.8%) were performed in neonates. Arterial switch operations (48 cases) were the most frequent procedures. Postoperatively, 11 (8.1%) patients required extracorporeal membrane oxygenation, and 4 (2.9%) patients had complete heart block. Postoperative in-hospital mortality was 11%. The median postoperative duration of mechanical ventilation, intensive care unit stay, and hospital length of stay were 6, 18, and 24 days, respectively. CONCLUSION: The early outcomes of neonatal cardiac surgery are encouraging. The requirement of postoperative extracorporeal membrane oxygenation support, postoperative intracranial hemorrhage, and acute kidney were identified as independent risk factors of mortality following surgery for congenital heart defects in neonates.


Assuntos
Cardiopatias Congênitas , Complicações Pós-Operatórias , Criança , Cardiopatias Congênitas/complicações , Mortalidade Hospitalar , Humanos , Recém-Nascido , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
9.
Neurosurg Clin N Am ; 33(2): 149-159, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35346447

RESUMO

Transradial access (TRA) has gained traction in neurointerventions as studies continue to demonstrate improved access site safety and equivalent end artery effectiveness when compared with traditional transfemoral techniques. Herein, we describe the technical nuances of obtaining TRA with a focus on distal TRA, left TRA, and sheathless TRA using larger bore catheters. We also discuss various strategies to avoid access site conversion if radial artery spasm or radial anomalies are encountered and offer some solutions for forming the Simmons catheter especially when it cannot be performed in the descending aorta. Lastly, we provide some insights regarding contraindications to TRA.


Assuntos
Cateterismo Periférico , Artéria Radial , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/métodos , Humanos , Artéria Radial/cirurgia , Resultado do Tratamento
10.
Int J Mol Sci ; 23(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055029

RESUMO

Electrically conductive materials that are fabricated based on natural polymers have seen significant interest in numerous applications, especially when advanced properties such as self-healing are introduced. In this article review, the hydrogels that are based on natural polymers containing electrically conductive medium were covered, while both irreversible and reversible cross-links are presented. Among the conductive media, a special focus was put on conductive polymers, such as polyaniline, polypyrrole, polyacetylene, and polythiophenes, which can be potentially synthesized from renewable resources. Preparation methods of the conductive irreversible hydrogels that are based on these conductive polymers were reported observing their electrical conductivity values by Siemens per centimeter (S/cm). Additionally, the self-healing systems that were already applied or applicable in electrically conductive hydrogels that are based on natural polymers were presented and classified based on non-covalent or covalent cross-links. The real-time healing, mechanical stability, and electrically conductive values were highlighted.


Assuntos
Materiais Biocompatíveis/química , Biopolímeros/química , Condutividade Elétrica , Hidrogéis/química , Animais , Fenômenos Químicos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Polimerização , Engenharia Tecidual
11.
Nat Prod Res ; 36(21): 5619-5625, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34894905

RESUMO

Stevioside is the major component of Stevia rebaudiana (Bertoni) leaves, family Asteraceae. UPLC-ESI-MS/MS analyses of leaves total methanol extract (TEx) and standardized butanol fraction (BF, 113.5 mg stevioside/g) were performed herein, revealing steviol glycosides, caffeoylquinic acid derivatives, flavonoids, and sesquiterpenoids. Their hepatoprotective activities against radiation-induced toxicity were evaluated compared to pure stevioside. Rats pretreatment with stevioside, TEx, and BF orally for 7 days before subjection to 6.5 Gy whole-body-gamma-irradiation reversed histopathological damages; improved liver functions and restored depleted antioxidants. ALT and reduced-glutathione levels showed insignificant changes, compared to control, by (5.22%, 3.20%, 24.90%) and (-0.47%, -3.95%, -2.63%), respectively. Glutathione-S-transferase, catalase, and MDA levels were significantly ameliorated. Liver tissue molecular profiling showed reduction in elevated TNF-α by 23.83%, 29.06%, 28.34%, respectively, and in NF-kB and COX-2 expression levels via immunohistochemical study. BF showed better hepatoprotective activity than TEx which may be attributed to higher stevioside, flavonoids, and caffeoylquinic acid derivatives content.


Assuntos
Diterpenos do Tipo Caurano , Glucosídeos , Lesões por Radiação , Stevia , Animais , Ratos , 1-Butanol , Butanóis , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Glutationa/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Stevia/química , Espectrometria de Massas em Tandem , Lesões por Radiação/tratamento farmacológico , Glucosídeos/química , Glucosídeos/farmacologia
12.
J Cosmet Dermatol ; 21(9): 3934-3942, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34932866

RESUMO

BACKGROUND: Trichoscopy is a simple noninvasive tool that is used in calculating different hair parameters and the diagnosis of different hair/scalp diseases at variable magnifications. OBJECTIVE: The aim of this work is to describe the features and parameters of hair and scalp in a healthy sample of Egyptian population using videodermoscopy. This may help to provide standard range of measurements of normal hair in both males and females. METHODS: A nonrandomized, observational study for features and parameters of hair structure, performed on 368 healthy Egyptian subjects with no hair/scalp complaint. RESULTS: Each scalp area has its own vascular pattern. Male subjects showed different values regarding their hair parameters from the female subjects. No significant difference was seen after application of hair dye, except for few values. In both genders, there was a change in hair parameters with age. Smoking had a negative influence on hair parameters. CONCLUSION: Hair features and parameters observed in our population are different from those reported by other populations. Smoking affects hair thickness and density. Dyed hair has greater thickness mostly due to the protective effect of hair conditioners.


Assuntos
Doenças do Cabelo , Tinturas para Cabelo , Dermoscopia , Feminino , Cabelo/diagnóstico por imagem , Doenças do Cabelo/diagnóstico por imagem , Doenças do Cabelo/etiologia , Humanos , Masculino , Couro Cabeludo
13.
Integr Cancer Ther ; 20: 15347354211060369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34825602

RESUMO

Recent reports have shown that bromelain (BL), a pineapple extract, acts as an adjuvant therapy in cancer treatment and prevention of carcinogenesis. The present study was designed to investigate the possible mechanisms by which BL could radiosensitize tumor cells in vitro and in a mouse tumor model. BL has shown a significant reduction in the viability of the radioresistant human breast carcinoma (MCF-7) cell line using cell proliferation assay. The in vivo study was designed using the Ehrlich model in female albino mice, treated with BL (6 mg/kg b. wt., intraperitoneal, once daily for 10 days) 1 hour before exposure to a fractionated dose of gamma radiation (5 Gy, 1 Gy for 5 subsequent days). The radiosensitizing effect of BL was evident in terms of a significant reduction in tumor volume, poly ADP ribose polymerase-1 (PARP-1), the proliferation marker Ki-67 and nuclear factor kappa activated B cells (NF-κB) with a significant elevation in the reactive oxygen species (ROS) content and lipid peroxidation (LPO) in tumor cells. The present findings offer a novel insight into the radiosensitizing effect of BL and its potential application in the radiotherapy course.


Assuntos
Bromelaínas , Radiossensibilizantes , Animais , Bromelaínas/farmacologia , Feminino , Antígeno Ki-67 , Camundongos , NF-kappa B , Inibidores de Poli(ADP-Ribose) Polimerases , Radiossensibilizantes/farmacologia
14.
Int J Biol Macromol ; 189: 114-123, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34418416

RESUMO

Encapsulation of volatile essential oils has been investigated to provide an active food packaging (AFP) material with more control over their fast release and pungent smell. In this work, Gum Arabic-based adhesive membrane was developed as a self-stick AFP material, delivering cinnamon essential oil (CEO) in vapor phase. Gum Arabic (GA) was grafted with butyl acrylate (BA) and hydroxyethyl methacrylate [GA-g-poly(BA-HEMA)]. Adhesive membrane was characterized by means of spectral, physicochemical and rheological analysis. GA-adhesive membrane made of 5% wt/v GA, 3.5 m mol HEMA, and 87 m mol BA with 21 N/m tack are loaded with 4, 8 and 10% v/v of CEO and used for antimicrobial bioassays. GA-g-poly(BA-HEMA) membrane prolonged CEO release up to 2 days. 8%v/v CEO showed superior activities against both Gram negative and positive bacteria. Shelf-life of cheese samples, packed with the self-stick membranes loaded with cinnamon extract, has extended from 3 to 8 weeks. Cheese samples that inoculated with shiga toxin producing E. coli O157:H7 and packed in plastic boxes with the self-stick AFP (4, 8 and 10 % CEO), showed significant reduction in the total bacteria counts.


Assuntos
Queijo , Cinnamomum zeylanicum/química , Embalagem de Alimentos , Goma Arábica/química , Membranas Artificiais , Extratos Vegetais/química , Acrilatos/química , Adesividade , Anti-Infecciosos/farmacologia , Emulsões/química , Escherichia coli/efeitos dos fármacos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Interações Hidrofóbicas e Hidrofílicas , Metacrilatos/química , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Polymers (Basel) ; 13(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34301035

RESUMO

From the environmental point of view, there is high demand for the preparation of polymeric materials for various applications from renewable and/or waste sources. New lignin-based spun fibers were produced, characterized, and probed for use in methylene blue (MB) dye removal in this study. The lignin was extracted from palm fronds (PF) and banana bunch (BB) feedstock using catalytic organosolv treatment. Different polymer concentrations of either a plasticized blend of renewable polymers such as polylactic acid/polyhydroxybutyrate blend (PLA-PHB-ATBC) or polyethylene terephthalate (PET) as a potential waste material were used as matrices to generate lignin-based fibers by the electrospinning technique. The samples with the best fiber morphologies were further modified after iodine handling to ameliorate and expedite the thermostabilization process. To investigate the adsorption of MB dye from aqueous solution, two approaches of fiber modification were utilized. First, electrospun fibers were carbonized at 500 °C with aim of generating lignin-based carbon fibers with a smooth appearance. The second method used an in situ oxidative chemical polymerization of m-toluidine monomer to modify electrospun fibers, which were then nominated by hybrid composites. SEM, TGA, FT-IR, BET, elemental analysis, and tensile measurements were employed to evaluate the composition, morphology, and characteristics of manufactured fibers. The hybrid composite formed from an OBBL/PET fiber mat has been shown to be a promising adsorbent material with a capacity of 9 mg/g for MB dye removal.

16.
J Cardiothorac Surg ; 16(1): 166, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099003

RESUMO

BACKGROUND: Re-exploration of bleeding after cardiac surgery is associated with significant morbidity and mortality. Perioperative blood loss and rate of re-exploration are variable among centers and surgeons. OBJECTIVE: To present our experience of low rate of re-exploration based on adopting checklist for hemostasis and algorithm for management. METHODS: Retrospective analysis of medical records was conducted for 565 adult patients who underwent surgical treatment of congenital and acquired heart disease and were complicated by postoperative bleeding from Feb 2006 to May 2019. Demographics of patients, operative characteristics, perioperative risk factors, blood loss, requirements of blood transfusion, morbidity and mortality were recorded. Logistic regression was used to identify predictors of re-exploration and determinants of adverse outcome. RESULTS: Thirteen patients (1.14%) were reexplored for bleeding. An identifiable source of bleeding was found in 11 (84.6%) patients. Risk factors for re-exploration were high body mass index, high Euro SCORE, operative priority (urgent/emergent), elevated serum creatinine and low platelets count. Re-exploration was significantly associated with increased requirements of blood transfusion, adverse effects on cardiorespiratory state (low ejection fraction, increased s. lactate, and prolonged period of mechanical ventilation), longer intensive care unit stay, hospital stay, increased incidence of SWI, and higher mortality (15.4% versus 2.53% for non-reexplored patients). We managed 285 patients with severe or massive bleeding conservatively by hemostatic agents according to our protocol with no added risk of morbidity or mortality. CONCLUSION: Low rate of re-exploration for bleeding can be achieved by strict preoperative preparation, intraoperative checklist for hemostasis implemented by senior surgeons and adopting an algorithm for management.


Assuntos
Algoritmos , Procedimentos Cirúrgicos Cardíacos , Lista de Checagem , Hemostasia Cirúrgica/normas , Assistência Perioperatória/normas , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Hemostasia Cirúrgica/métodos , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/prevenção & controle , Reoperação , Estudos Retrospectivos , Fatores de Risco
17.
Int J Biol Macromol ; 182: 1820-1831, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34052272

RESUMO

Developing a multifunctional wound dressing that protects, cures and indicates the healing progress, is a new approach of investigation. Red cabbage extract (RCE), consisting of bioactive compounds that have antioxidant, anti-inflammatory, anti-carcinogenic, bactericidal, antifungal, and antiviral activities, was utilized as a natural pH-sensitive indicator. Chitosan-based hydrogel, encapsulating RCE, was developed to obtain a smart therapeutic pH-sensitive wound dressing as antimicrobial bio-matrix provides a comfortable cushion for wound bed and indicates its status. Methacrylated-chitosan was crosslinked by different concentrations of methylenebisacrylamide (MBAA) by which hydrogel mechanical and morphological properties were tuned. The proposed mechanism for hydrogel formation was confirmed by FT-IR. The coloristic properties of the RCE and the changes in color intensity as a function of pH were confirmed by UV-Vis spectroscopy. The effect of MBAA on the mechanical, swelling, release and morphological properties of hydrogel were investigated. MBAA (2.5% wt/v) in 2% wt/v chitosan showed preferable mechanical (20 KPa), swelling (1294% at pH 8 ± 0.2), and release (prolonged up to 5 days) properties. Hydrogel matrices, loaded on cotton gauze submerged in different pH buffer solutions, showed explicit color changes from green to red as pH changed from 9 to 4.


Assuntos
Bandagens , Brassica/química , Quitosana/farmacologia , Hidrogéis/farmacologia , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Acrilamidas/química , Antocianinas/análise , Quitosana/química , Colorimetria , Concentração de Íons de Hidrogênio , Fenômenos Mecânicos , Porosidade , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Cardiothorac Surg ; 16(1): 110, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892770

RESUMO

BACKGROUND: Pericardial patches are often used for repair of congenital cardiac defects. The aim of this study was to describe our initial experience with the use of equine pericardium and its safety and advantages and disadvantages compared to bovine pericardium. METHODS: We designed a retrospective cohort study of 111 patients who were surgically treated for congenital heart disease between 2017 and 2020. Equine pericardium was used in 58 patients and bovine pericardium was used in 53 patients. Recorded variables included demographic data, preoperative cardiac pathology, site of patch insertion, morbidity and mortality. RESULTS: The overall survival rate was 94.5% and no deaths were related to patch insertion. None of our patients were reoperated on for patch related complications. Postoperative transcatheter intervention was needed in 2 patients (1.8%): one for dilatation of aortic arch stenosis after repair of hypoplastic left heart syndrome with equine pericardium and one for dilatation of pulmonary artery branches after repair of tetralogy of Fallot using bovine pericardium. CONCLUSIONS: Equine pericardium is a safe patch material for reconstruction in congenital heart surgery. It may be preferable to bovine pericardium in cases requiring a complex shape or a pliable patch as in in arch reconstruction or for valve reconstruction.


Assuntos
Aorta Torácica/cirurgia , Bioprótese , Procedimentos Cirúrgicos Cardíacos/métodos , Cardiopatias Congênitas/cirurgia , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Pericárdio/cirurgia , Adolescente , Adulto , Animais , Bovinos , Criança , Pré-Escolar , Feminino , Cavalos , Humanos , Lactente , Recém-Nascido , Masculino , Procedimentos de Cirurgia Plástica , Reoperação , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
19.
Int J Radiat Biol ; 97(5): 632-641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33635746

RESUMO

PURPOSE: Cyclophosphamide (Cyp) is one of the most commonly used, wide spectrum chemotherapeutic agents. Cyp has multi-organ toxicities that are dose limiting, thus it's mostly used in chemotherapeutic combinations. Radiation is well known as a hazardous sort of energy, recent studies are interested in studying the beneficial therapeutic effects of low-dose gamma radiation. This study examined the protective effect of two different doses/dose-rates of irradiation either alone or combined with telmisartan against Cyp-induced cardiotoxicity. MATERIALS AND METHODS: Rats were divided into seven groups; (1): Control, (2): Cyp, (3-4): 0.05 Gy low dose rate (LDR) irradiation, 0.25 Gy high dose rate (HDR) irradiation, respectively, prior to Cyp dose, (5-7): telmisartan either alone or with 0.05 Gy LDR-irradiation or 0.25 Gy HDR-irradiation, respectively, prior to Cyp dose. The current investigation studied the effect of Cyp alone or combined with different treatment regimens on serum cTn-I and LDH, nuclear factor-κB (NF-κB) pathway (p65/IκB/IKK-α/IKK-ß) in the myocardium. Pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α were assessed in addition to histopathological examination of the heart. RESULTS: Low-dose irradiation attenuated cardiac enzymes, pro-inflammatory cytokines, NF-κB content, and histology, in both low and HDRs. Furthermore, the combination of low-dose irradiation with telmisartan (an angiotensin-II receptor type-1 blocker and a known cardio-protective drug) offered the best histological results. CONCLUSIONS: Low-dose irradiation-induced amelioration is partially but not completely through canonical activation of NF-κB, and may have another atypical pathway. While telmisartan probably ameliorates NF-κB totally through canonical pathway.


Assuntos
Ciclofosfamida/toxicidade , Raios gama , Coração/efeitos dos fármacos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Citocinas/metabolismo , Relação Dose-Resposta à Radiação , Coração/efeitos da radiação , Masculino , Ratos
20.
Am J Dermatopathol ; 43(9): 653-655, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577178

RESUMO

ABSTRACT: Crystalglobulinemia (CG) is a rare disorder characterized by crystallization of monoclonal immunoglobulins in the microcirculation leading to multiorgan vascular thrombosis and ischemic injury. The main cause of CG is multiple myeloma. We report a case of a 52-year-old man who presented with widespread necrotizing plaques and ulcerations. A skin biopsy revealed eosinophilic rectangular-shaped crystals occluding the lumina of blood vessels with no associated features of vasculitis. The crystals were Periodic acid-Schiff stain positive. The findings were diagnostic of CG. Extensive work up lead to the discovery of multiple myeloma. Awareness of CG is important because it may be the first presenting manifestation of an underlying serious hematological malignancy.


Assuntos
Imunoglobulinas/sangue , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/patologia , Úlcera Cutânea/patologia , Vasos Sanguíneos , Cristalização , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Úlcera Cutânea/etiologia
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