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1.
Crit Rev Food Sci Nutr ; 61(6): 1027-1037, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32345036

RESUMEN

During the processing of the fishery resources, the significant portion is either discarded or used to produce low-value fish meal and oil. However, the discarded portion is the rich source of valuable proteins such as collagen, vitamins, minerals, and other bioactive compounds. Collagen is a vital protein in the living body as a component of a fibrous structural protein in the extracellular matrix, connective tissue and building block of bones, tendons, skin, hair, nails, cartilage and joints. In recent years, the use of fish collagen as an increasingly valuable biomaterial has drawn considerable attention from biomedical researchers, owing to its enhanced physicochemical properties, stability and mechanical strength, biocompatibility and biodegradability. This review focuses on summarizing the growing role of fish collagen for biomedical applications. Similarly, the recent advances in various biomedical applications of fish collagen, including wound healing, tissue engineering and regeneration, drug delivery, cell culture and other therapeutic applications, are discussed in detail. These applications signify the commercial importance of fish collagen for the fishing industry, food processors and biomedical sector.


Asunto(s)
Materiales Biocompatibles , Colágeno , Animales , Matriz Extracelular , Ingeniería de Tejidos , Cicatrización de Heridas
2.
J Nanobiotechnology ; 19(1): 38, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33546702

RESUMEN

BACKGROUND: Increasing antibiotic resistance continues to focus on research into the discovery of novel antimicrobial agents. Due to its antimicrobial and wound healing-promoting activity, metal nanoparticles have attracted attention for dermatological applications. This study is designed to investigate the scope and bactericidal potential of zinc ferrite nanoparticles (ZnFe2O4 NPs), and the mechanism of anti-bacterial action along with cytocompatibility, hemocompatibility, and wound healing properties. RESULTS: ZnFe2O4 NPs were synthesized via a modified co-precipitation method. Structure, size, morphology, and elemental compositions of ZnFe2O4 NPs were analyzed using X-ray diffraction pattern, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. In PrestoBlue and live/dead assays, ZnFe2O4 NPs exhibited dose-dependent cytotoxic effects on human dermal fibroblasts. In addition, the hemocompatibility assay revealed that the NPs do not significantly rupture red blood cells up to a dose of 1000 µg/mL. Bacterial live/dead imaging and zone of inhibition analysis demonstrated that ZnFe2O4 NPs showed dose-dependent bactericidal activities in various strains of Gram-negative and Gram-positive bacteria. Interestingly, NPs showed antimicrobial activity through multiple mechanisms, such as cell membrane damage, protein leakage, and reactive oxygen species generation, and were more effective against gram-positive bacteria. Furthermore, in vitro scratch assay revealed that ZnFe2O4 NPs improved cell migration and proliferation of cells, with noticeable shrinkage of the artificial wound model. CONCLUSIONS: This study indicated that ZnFe2O4 NPs have the potential to be used as a future antimicrobial and wound healing drug.


Asunto(s)
Antibacterianos/farmacología , Compuestos Férricos/farmacología , Nanopartículas , Cicatrización de Heridas/efectos de los fármacos , Zinc/farmacología , Animales , Antibacterianos/química , Línea Celular , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Infecciones por Escherichia coli/tratamiento farmacológico , Compuestos Férricos/química , Hemólisis/efectos de los fármacos , Humanos , Ratones , Células 3T3 NIH , Nanopartículas/química , Nanopartículas/ultraestructura , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Zinc/química
3.
J Environ Manage ; 262: 110318, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250801

RESUMEN

Groundwater with an excessive level of Arsenic (As) is a threat to human health. In Bangladesh, out of 64 districts, the groundwater of 50 and 59 districts contains As exceeding the Bangladesh (50 µg/L) and WHO (10 µg/L) standards for potable water. This review focuses on the occurrence, origin, plausible sources, and mobilization mechanisms of As in the groundwater of Bangladesh to better understand its environmental as well as public health consequences. High As concentrations mainly was mainly occur from the natural origin of the Himalayan orogenic tract. Consequently, sedimentary processes transport the As-loaded sediments from the orogenic tract to the marginal foreland of Bangladesh, and under the favorable biogeochemical circumstances, As is discharged from the sediment to the groundwater. Rock weathering, regular floods, volcanic movement, deposition of hydrochemical ore, and leaching of geological formations in the Himalayan range cause As occurrence in the groundwater of Bangladesh. Redox and desorption processes along with microbe-related reduction are the key geochemical processes for As enrichment. Under reducing conditions, both reductive dissolution of Fe-oxides and desorption of As are the root causes of As mobilization. A medium alkaline and reductive environment, resulting from biochemical reactions, is the major factor mobilizing As in groundwater. An elevated pH value along with decoupling of As and HCO3- plays a vital role in mobilizing As. The As mobilization process is related to the reductive solution of metal oxides as well as hydroxides that exists in sporadic sediments in Bangladesh. Other mechanisms, such as pyrite oxidation, redox cycling, and competitive ion exchange processes, are also postulated as probable mechanisms of As mobilization. The reductive dissolution of MnOOH adds dissolved As and redox-sensitive components such as SO42- and oxidized pyrite, which act as the major mechanisms to mobilize As. The reductive suspension of Mn(IV)-oxyhydroxides has also accelerated the As mobilization process in the groundwater of Bangladesh. Infiltration from the irrigation return flow and surface-wash water are also potential factors to remobilize As. Over-exploitation of groundwater and the competitive ion exchange process are also responsible for releasing As into the aquifers of Bangladesh.


Asunto(s)
Arsénico , Agua Subterránea , Contaminantes Químicos del Agua , Bangladesh , Monitoreo del Ambiente , Sedimentos Geológicos , Humanos
4.
Appl Microbiol Biotechnol ; 103(5): 1989-2006, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30637497

RESUMEN

The bacterial infections have always a serious problem to public health. Scientists are developing new antibacterial materials to overcome this problem. Polysaccharides are promising biopolymers due to their diverse biological functions, low toxicity, and high biodegradability. Chitin and chitosan have antibacterial properties due to their cationic nature, while cellulose/bacterial cellulose does not possess any antibacterial activity. Moreover, the insolubility of chitin in common solvents, the poor solubility of chitosan in water, and the low mechanical properties of chitosan have restricted their biomedical applications. In order to solve these problems, chemical modifications such as quaternization, carboxymethylation, cationization, or surface modification of these polymers with different antimicrobial agents, including metal and metal oxide nanoparticles, are carried out to obtain new materials with improved physiochemical and biological properties. This mini review describes the recent progress in such derivatives and composites with potential antibacterial applications.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Celulosa/farmacología , Quitina/farmacología , Quitosano/farmacología , Descubrimiento de Drogas/métodos , Celulosa/química , Quitina/química , Quitosano/química , Humanos , Nanopartículas del Metal/química , Metales/química
5.
Pharm Biol ; 57(1): 736-743, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31652081

RESUMEN

Contexts: Sauromatum guttatum (Wall.) Schott (Araceae) has been traditionally used for the treatment of wounds. Objectives: This study evaluates the healing and tissue regeneration potential of S. guttatum extract in burn wounds. Materials and methods: S. guttatum extract was analysed using various chemical tests, thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Moreover, the extract was tested against burn associated bacteria and minimum inhibitory concentration (MIC) was also calculated. Wound healing and tissue regeneration potential was assessed using a thermally induced burn BALBc mouse model. S. guttatum extract (2% w/w) prepared in petroleum jelly, vehicle and positive control [silver sulfadiazine (SD)] groups was applied three times a day. The treatment was continued for 15 d and wound closure was measured and photographed on day 5, 10 and 15. The burnt tissues excised from wounds were subjected to histological and comparative gene expression analysis. Results: The results of the chemical tests indicated the presence of alkaloids, saponins, phenols, phytosterols, tannins, and flavonoids, while TLC and HPLC analysis indicated the presence of various compounds. The extract showed excellent activity against the tested pathogens. The lowest MIC (125 µg/mL) was observed against Staphylococcus aureus. A considerable decrease in wound area (72%) was observed in extract-treated group. Histological examination of extract-treated group showed good signs of wound healing with complete re-epithelialization and better tissue regeneration. Comparative gene expression analysis revealed the up-regulation of wound healing related PDGF, EGF and FGF genes. Conclusions: S. guttatum extract may be used to isolate bioactive constituents for the treatment of burn wounds.


Asunto(s)
Araceae/química , Quemaduras/tratamiento farmacológico , Extractos Vegetales/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Quemaduras/patología , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Modelos Animales de Enfermedad , Factor de Crecimiento Epidérmico/genética , Factores de Crecimiento de Fibroblastos/genética , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Factor de Crecimiento Derivado de Plaquetas/genética , Sulfadiazina de Plata/farmacología , Staphylococcus aureus/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Cicatrización de Heridas/genética
6.
Microb Pathog ; 118: 154-158, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29571723

RESUMEN

Hepatitis C is a serious health issue and cause liver disorders in millions of people. Available therapeutic agents require long term administration with numerous side effects. Therefore, there is a dire need to find alternative treatment options for this disease. Since ancient times, medicinal plants are widely used to cure various diseases with no or less harmful effects. Therefore, this study was designed to find out phytochemicals and investigate antiviral activity of methanol extract of Ajuga bracteosa, Ajuga parviflora, Berberis lycium and Citrus lemon against Hepatitis C Virus (HCV infection). Phytochemical analysis of the plant extract was performed using various chemical tests. Toxicity of the plant extract was determined against using trypan blue exclusion method. Antiviral activity of the selected plant extract was find out against HCV infected HepG2 cells. For this purpose, HepG2 cells were seeded with HCV positive and negative serum and nontoxic doses of plant extract for 24 and 48 h. After this RNA was extracted and viral load was determined using Real-time PCR. Phytochemical analysis showed the presence of flavonoids and phenols in all plant extracts while amino acids, alkaloids and tannins were present in B. lycium and saponins were detected in C. lemon. Toxicity assay showed that all plant extracts were nontoxic at maximum concentration of 200 µg/ml except B. lycium, which showed mild toxicity at 40 µg/ml and were extremely toxic at 60 µg/ml and above doses. Real-time PCR quantitation result revealed that after 24 h treatments A. parviflora showed highest antiviral activity, followed by A. bracteosa, while B. lycium extract had low (35%) and C. lemon has no antiviral effects. The 48 h treatments showed an increase antiviral activity by A. bracteosa followed by A. parviflora and B. lycium while C. lemon showed negative effect. Our results depicted that mentioned plants might be used as an alternative therapeutic regime or in combination with existing treatments against HCV.


Asunto(s)
Ajuga/química , Antivirales/farmacología , Berberis/química , Citrus/química , Hepacivirus/efectos de los fármacos , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Adulto , Anciano , Alcaloides/análisis , Aminoácidos/análisis , Proliferación Celular/efectos de los fármacos , Femenino , Flavonoides/análisis , Células Hep G2/efectos de los fármacos , Células Hep G2/virología , Hepatitis C/tratamiento farmacológico , Hepatocitos/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Fenoles/análisis , Extractos Vegetales/química , Plantas Medicinales/química , Taninos/análisis , Carga Viral , Adulto Joven
7.
Neurol Sci ; 39(2): 207-214, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29079885

RESUMEN

Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease of the central nervous system (CNS), characterized by demyelination, neuronal injury, and breaching of the blood-brain barrier (BBB). Epidemiological studies have shown that immunological, genetic, and environmental factors contribute to the progression and development of MS. T helper 17 (Th17) cells are crucial immunological participant in the pathophysiology of MS. The aberrant production of IL-17 and IL-22 by Th17 cells crosses BBB promotes its disruption and interferes with transmission of nerve signals through activation of neuroinflammation in the CNS. These inflammatory responses promote demyelination through transcriptional activation of signal transducers and activators of transcription-1 (STAT-1), nuclear factor kappa-B (NF-κB), matrix metalloproteinases (MMPs), interferon ϒ (IFNϒ), and Src homology region 2 domain-containing phosphatase-1 (SHP-1). B cells also contribute to disease progression through abnormal regulation of antibodies, cytokines, and antigen presentation. Additionally, oxidative stress has been known as a causative agent for the MS. Curcumin is a hydrophobic yellowish diphenolic component of turmeric, which can interact and modulate multiple cell signaling pathways and prevent the development of various autoimmune neurological diseases including MS. Studies have reported curcumin as a potent anti-inflammatory, antioxidant agent that could modulate cell cycle regulatory proteins, enzymes, cytokines, and transcription factors in CNS-related disorders including MS. The current study summarizes the reported knowledge on therapeutic potential of curcumin against MS, with future indication as neuroprotective and neuropharmacological drug.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Curcumina/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Humanos , Esclerosis Múltiple/fisiopatología
8.
BMC Complement Altern Med ; 16: 251, 2016 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-27465545

RESUMEN

BACKGROUND: Viscum album has shown inhibitory effect on different smooth muscles but underlying mechanisms in gut and vascular smooth muscles are not well defined. Additionally, the plant has also importance in managing hyperactive gut and cardiovascular disorders. The current study was aimed to probe a pharmacological base of the smooth muscle relaxant effect of V. album in gut and vascular preparations. METHODS: V. album crude extract (Va. Cr) and its ethyl acetate fraction (Va. EtAc) were studied using in vitro techniques. The antispasmodic activity was performed using isolated rabbit jejunum while the vasorelaxant effects were studied in rabbit aortic rings. RESULTS: Va. Cr and Va. EtAc inhibited spontaneous and high K(+)-induced contractions with EC50 values of 0.31 mg/mL (0.15-0.57) and 0.62 mg/mL (0.3-0.95), respectively. This advocates an antispasmodic effect probably operated through calcium channels blockade (CBB). The proposed mechanism was confirmed by a pretreatment of the tissue with Va. Cr (0.01-0.3 mg/mL), which shifted the Ca(++) concentration-response curves (CRCs) rightward, similar to verapamil. Moreover, Va. Cr showed a partial relaxation against high K(+) and PE (1 µM) induced contractions in isolated rabbit aorta rings. Va. EtAc caused complete relaxation of high K(+) precontraction and partially relaxed PE (1 µM) induced contractions, suggesting inhibitory effect on Ca(++) entry, in addition to other possible mechanisms. CRCs were shifted to the right correspondingly to verapamil when the aortic rings were pretreated with Va. Cr and Va. EtAc. CONCLUSIONS: These data indicated that Va. Cr possesses smooth muscle relaxant effect mediated through voltage-dependent Ca(++) channel blockade (CCB), which explains its spasmolytic and vasorelaxant activity. The CCB activity is concentrated more in Va. EtAc. This study provides an evidence for the medicinal importance of V. album in gut spasm and possibly hypertension.


Asunto(s)
Aorta/efectos de los fármacos , Yeyuno/efectos de los fármacos , Parasimpatolíticos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Viscum album/química , Animales , Bloqueadores de los Canales de Calcio/farmacología , Hipertensión , Músculo Liso Vascular/efectos de los fármacos , Conejos , Vasodilatadores/farmacología
9.
Pharm Biol ; 54(11): 2679-2684, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27181135

RESUMEN

CONTEXT: Psidium guajava L. (Myrtaceae) is widely used in traditional medicine for the treatment of various ailments including cardiovascular and gastrointestinal disorders. OBJECTIVES: The current study investigated the chemical composition and cardiovascular and gastrointestinal effects of the essential oil of P. guajava. MATERIALS AND METHODS: The chemical composition of the essential oil was investigated using gas chromatography-mass spectrometry (GC-MS) technique. The biological activity of the essential oil was tested on rabbit aorta and jejunum. All changes in isometric tension were recorded through a force transducer coupled with a bridge amplifier data acquisition system. RESULTS AND DISCUSSION: GC-MS analysis showed the presence of butanoic acid methyl ester, 3-methyl glutaric anhydride, 1-butanol, 3-hexenal, cinnamyl alcohol, 1-hexanol and hexane as the major components. In isolated rabbit aorta preparations, the essential oil showed vasorelaxation at doses of 3-10 mg/mL against high K+ and phenylephrine pre-contractions with EC50 values of 5.52 (5-6.04) and 6.23 mg/mL (5.0-7.46). The essential oil inhibited spontaneous and high K+ induced contractions in isolated rabbit jejunum with EC50 values of 0.84 (0.3-1.38) and 0.71 mg/mL (0.3-1.12) and shifted Ca + 2 concentration curves to the right, similar to verapamil, suggesting spasmolytic activity mediated possibly through Ca + 2 channel blockade. CONCLUSIONS: In summary, the data indicated the presence of seven different phytoconstituents in the essential oil of P. guajava and calcium channel blocking activity, which provides a pharmacological base to the traditional use of P. guajava in cardiovascular and gastrointestinal disorders. Further studies are suggested to explore the molecular nature of these effects.


Asunto(s)
Aceites Volátiles/farmacología , Parasimpatolíticos/farmacología , Psidium/química , Animales , Frutas/química , Masculino , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Aceites Volátiles/análisis , Conejos
10.
J Food Sci Technol ; 52(12): 8343-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26604413

RESUMEN

Bacterial cellulose (BC) has been given an ample attention due to its high potential for many industrial applications. However, the high cost of production medium has hindered the commercialization of BC. Several efforts have been made to explore cheep, raw and waste sources for BC production. The current study aims at investigating the BC production from a waste source; the scum obtained during preparation of sugarcane jaggery or gur (JS). JS was five-fold diluted with distilled water and used as culturing medium without any additional nutrients. The production of BC was monitored till 10th days of cultivation both at static and shaking culturing conditions. A maximum of 2.51 g/L and 2.13 g/L BC was produced in shaking and static cultures, respectively, after 10 days. The structure features of BC were confirmed through FTIR, XRD and SEM analysis. The chemical structure and physical appearance strongly resembled the BC produced form synthetic media. It was noteworthy that the BC produced from JS showed higher mechanical and thermal properties. The cell adhesion and proliferation capabilities of produced BC were observed that depicted definite animal cell adhesion without any considerable cytotoxicity. Besides providing an economically feasible way for BC production, the high level of physico-mechanical and biological properties insured the importance in medical fields.

11.
J Nanosci Nanotechnol ; 14(1): 803-14, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24730299

RESUMEN

Nanotechnology-based drug delivery systems have the potential to enhance the efficacy of poorly soluble systemic drugs. Curcumin, a yellow pigment isolated from turmeric, possesses a wide range of pharmacological activities, including anticancer effects. The anticancer potential of curcumin is mediated through the inhibition and modulation of several intracellular signaling pathways, as confirmed in various in vitro and in vivo cancer studies. However, clinical application of dietary curcumin for the treatment of cancer and other chronic diseases have been hindered by poor bioavailability, due to low systemic solubility as well as rapid metabolism and elimination from the body. Different techniques for sustained and efficient curcumin delivery, including nanoparticles, liposomes, micelles, phospholipids, and curcumin-encapsulated polymer nanoparticles are the focus of this study. Previous studies have shown that nanocurcumin has improved anticancer effects as compared to normal curcumin formulations. Among nanoformulations, few composite nanosystems have the simultaneous properties of therapeutic activity and multifunctional nanoparticles as enhanced image contrast agents. We also address the challenges to the development of nanocurcumin delivery platforms by enhancing a steady aqueous dispersion state. Further studies are needed using preclinical and clinical cancer models to recommend nanocurcumin as a drug of choice for cancer therapy.


Asunto(s)
Curcumina/administración & dosificación , Curcumina/química , Nanocápsulas/administración & dosificación , Nanocápsulas/química , Neoplasias/tratamiento farmacológico , Absorción , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Cristalización/métodos , Difusión , Composición de Medicamentos/métodos , Diseño de Fármacos , Humanos , Nanocápsulas/efectos de la radiación
12.
Mar Pollut Bull ; 205: 116657, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38950514

RESUMEN

Pakistan, a country with limited water resources and highly vulnerable to the adverse effects of climate change, faces numerous challenges in managing its water supply. In this sense, this study assessed potentially toxic elements (PTEs) in the surface water and sediments of Pakistan's Indus River and its tributaries. Key water quality parameters such as pH, electrical conductivity (EC), and total dissolved solids (TDS) were determined, with respective average values of 7.1, 40 µS/cm, and 208 mg L-1. The concentrations of Cd, Cr, Cu, Ni, and Zn in surface water samples averaged 26 µg L-1, 0.9 µg L-1, 1.4 µg L-1, 22 µg L-1, and 2.1 µg L-1, respectively. The general sediment PTE profile was Ni > Cd > Zn > Cu > Cr. Certain PTE levels exceeded recommended thresholds, indicating the establishment of environmental pollution. Calculated geo-accumulation index values suggested moderate to heavy pollution levels in sediment, with PERI (404) values reinforcing the ecological risk posed by elevated PTE concentrations. Furthermore, significant correlations were observed between specific PTE pairs in both water and sediment samples. This study contributes with novel insights into the distribution and ecological implications of PTE contamination in the Indus River and its tributaries, paving the way for ecological risk management efforts.

13.
Adv Healthc Mater ; 12(31): e2301551, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37300448

RESUMEN

Hemorrhage and bacterial infections are major hurdles in the management of life-threatening surgical wounds. Most bioadhesives for wound closure lack sufficient hemostatic and antibacterial properties. Furthermore, they suffer from weak sealing efficacy, particularly for stretchable organs, such as the lung and bladder. Accordingly, there is an unmet need for mechanically robust hemostatic sealants with simultaneous antibacterial effects. Here, an injectable, photocrosslinkable, and stretchable hydrogel sealant based on gelatin methacryloyl (GelMA), supplemented with antibacterial zinc ferrite (ZF) nanoparticles and hemostatic silicate nanoplatelets (SNs) for rapid blood coagulation is nanoengineered. The hydrogel reduces the in vitro viability of Staphylococcus aureus by more than 90%. The addition of SNs (2% w/v) and ZF nanoparticles (1.5 mg mL-1 ) to GelMA (20% w/v) improves the burst pressure of perforated ex vivo porcine lungs by more than 40%. Such enhancement translated to ≈250% improvement in the tissue sealing capability compared with a commercial hemostatic sealant, Evicel. Furthermore, the hydrogels reduce bleeding by ≈50% in rat bleeding models. The nanoengineered hydrogel may open new translational opportunities for the effective sealing of complex wounds that require mechanical flexibility, infection management, and hemostasis.


Asunto(s)
Hemostáticos , Hidrogeles , Ratas , Porcinos , Animales , Hidrogeles/farmacología , Hemostáticos/farmacología , Hemostasis , Antibacterianos/farmacología , Silicatos/farmacología
14.
Sci Total Environ ; 873: 162438, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36842591

RESUMEN

The complication of stent implantation is the biggest obstacle to the success of its clinical application. In this study, we developed a combination way of 3D printing and the coating technique for preparation of functional polyurethane stents against stent implantation-induced thrombosis and postoperative infection. SEM, XPS, static water contact angle, and XRD demonstrated that the functional polyurethane stent had a 37 µm-thickness membrane composed of zein nanospheres (250-350 nm). Meanwhile, ZnO nanoparticles were encapsulated in zein nanospheres while heparin was adsorbed on the surface, causing 97.1 ± 6.4 % release of heparin in 120 min (first-order kinetic model) and 62.7 ± 5.6 % release of Zn2+ in 9 days (Korsmeyer-Peppas model). The mechanical analysis revealed that the functional polyurethane stents had about 8.61 MPa and 2.5 MPa tensile strength and bending strength, respectively. The in vitro biological analysis showed that the functional polyurethane stents had good EA.hy926 cells compatibility (97.9 ± 3.8 %), anti-coagulation response (comparable plasma protein, platelet adhesion and suppressed clotting) and sustained antibacterial activities by comparison with the bare polyurethane stent. The preliminary evaluation by rabbit ex vivo carotid artery intervention experiment demonstrated that the functional polyurethane stents could maintain blood circulation under the continuous stresses of blood flow. Meanwhile, the detailed data from the simulated implant infection experiment in vivo showed the functional polyurethane stents could effectively reduce microbial infection by 3-6 times lower and improve fibrosis and macrophage infiltration.


Asunto(s)
Nanosferas , Trombosis , Zeína , Animales , Conejos , Poliuretanos , Nanosferas/efectos adversos , Trombosis/etiología , Heparina/farmacología , Stents/efectos adversos
15.
Adv Mater ; 35(38): e2303047, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37363951

RESUMEN

Constructing Van der Waals heterojunction is a crucial strategy to achieve excellent photocatalytic activity. However, in most Van der Waals heterojunctions synthesized by ex situ assembly, electron transfer encounters huge hindrances at the interface between the two components due to the large spacing and potential barrier. Herein, a phosphate-bridged Van der Waals heterojunction of cobalt phthalocyanine (CoPc)/tungsten disulfide (WS2 ) bridged by phosphate (xCoPc-nPO4 - -WS2 ) is designed and prepared by the traditional wet chemistry method. By introducing a small phosphate molecule into the interface of CoPc and WS2 , creates an electron "bridge", resulting in a compact combination and eliminating the space barrier. Therefore, the phosphate (PO4 - ) bridge can serve as an efficient electron transfer channel in heterojunction and can efficiently transmit photoelectrons from WS2 to CoPc under excited states. These excited photoelectrons are captured by the catalytic central Co2+ in CoPc and subsequently convert CO2 molecules into CO and CH4 products, achieving 17-fold enhancement on the 3CoPc-0.6PO4 - -WS2 sample compared to that of pure WS2 . Introducing a small molecule "bridge" to create an electron transfer channel provides a new perspective in designing efficient photocatalysts for photocatalytic CO2 reduction into valuable products.

16.
J Healthc Eng ; 2022: 9581387, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35399840

RESUMEN

Prior to COVID-19, the tourism industry was one of the important sectors of the world economy. This study intends to measure the perception of Chinese tourists concerning the spread of COVID-19 in China. The crowding perception, xenophobia, and ethnocentrism are the measurement indicators of the study. A five-point Likert scale is used to predict the perception of the tourists in various destinations. The Kaiser-Mayer-Olkin test and Cronbach's alpha are conducted to ensure the validity and reliability of the corresponding items. SPSS version 21 is used to obtain factor loading, mean values, and standard deviation. Regression analysis is used to measure the strength of the constructs' relationship and prove the hypotheses. Questionnaires have been filled from 730 Chinese respondents. Artificial neural networks and confusion matrices are used for validation and performance evaluation, respectively. Results show that crowding perception, xenophobia, and ethnocentrism caused the spread of COVID-19 during the epidemic. Hence, the tourism industry in China is adversely affected by COVID-19. The crisis management stakeholders of the country need to adopt policies to reduce the spread of COVID-19. The tourism sector needs to provide confidence to the tourists. It will provide ground for the mental strength of the tourists in China.


Asunto(s)
COVID-19 , COVID-19/epidemiología , China/epidemiología , Humanos , Redes Neurales de la Computación , Reproducibilidad de los Resultados , Turismo
17.
Comput Intell Neurosci ; 2022: 8330702, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35154308

RESUMEN

Cycloaromatic hydrocarbons are a type of potentially hazardous chemicals that are widely present in the environment and pose a serious threat to human health. However, the traditional research methods for their detection process are cumbersome, the detection cycle is long, and the sensitivity is low. In response to the above problems, this article combines the molecular fingerprint information characteristics of surface-enhanced Raman scattering technology to simulate the four polycyclic aromatic hydrocarbons of pyrene, anthracene, phenanthrene, and trichenium and quantitative detection of cyclic aromatic hydrocarbons and four kinds of polycyclic aromatic hydrocarbon mixtures. The experimental results show that the PAHs based on SERS have the advantages of higher sensitivity and high selectivity, which verifies the accuracy and feasibility of the method in this article.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Humanos , Espectrometría Raman
18.
Bioresour Technol ; 360: 127600, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35820558

RESUMEN

This study emphasizes on the cellulase production characteristics of strain ZY7 and its collaboration with nitrate-dependent ferrous oxidizing (NFO) strain XL4 to achieve efficient denitrification at low carbon-to-nitrogen (C/N) ratio. Results indicated that the denitrification efficiency increased from 65.47 to 97.99% at 24 h after co-culture at C/N of 1.0. Three-dimensional fluorescence excitation-emission matrix (3D-EEM) showed significant changes in the intensity of soluble microbial products (SMP), fulvic-like materials, and aromatic proteins after co-culture. Bio-precipitates were characterized by Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FTIR), and X-ray diffraction (XRD), which showed that cellulose structure was disrupted and the metabolites were potential carbon source for denitrification. In addition, cellulase activity suggested that the hydrolysis of ß-1,4-glycosidic bonds and oligosaccharides may be the rate-limiting steps in cellulose degradation. This work promoted the understanding of denitrification characteristics of co-culture and expanded the application of cellulose degrading bacteria in sewage treatment.


Asunto(s)
Celulasa , Cupriavidus , Reactores Biológicos/microbiología , Carbono/química , Celulasa/metabolismo , Celulosa , Cupriavidus/metabolismo , Desnitrificación , Nitratos/metabolismo , Nitrógeno/química
19.
Saudi J Biol Sci ; 29(6): 103271, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35392596

RESUMEN

Equisetum arvense L. is widely used as a traditional medicine for the management of inflammation and cancer. In the present study, phyto-chemical analysis of E. arvense was carried out and its cytotoxic potential against human melanoma (MDA-MB-435) and ovarian cancer cells (OVCAR3) was evaluated. Phyto-chemical profile of E. arvense methanolic extract and its fractions was established employing UHPLC-MS/MS and Global Natural Product Social molecular networking. Cytotoxic activity was evaluated using absorbance assay (CellTiter-Blue® Cell Viability Assay). Overall, 22 compounds were identified in the crude extract and polarity-based fractions of E. arvense. Flavonoids, flavonoid-O-glycosides and phenolic acids were found to be the major classes of phyto-chemicals. In addition, the crude extract of E. arvense and its fractions were found active against the tested cell lines. The highest anti-cancer activity against OVCAR3 cells was exhibited by the n-hexane fraction. These results indicated that E. arvense is rich in flavonoids and might be used for the development of anti-cancer drugs against melanoma and ovarian cancers.

20.
J Healthc Eng ; 2022: 1678000, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991297

RESUMEN

The process of pneumonia detection has been the focus of researchers as it has proved itself to be one of the most dangerous and life-threatening disorders. In recent years, many machine learning and deep learning algorithms have been applied in an attempt to automate this process but none of them has been successful significantly to achieve the highest possible accuracy. In a similar attempt, we propose an enhanced approach of a deep learning model called restricted Boltzmann machine (RBM) which is named enhanced RBM (ERBM). One of the major drawbacks associated with the standard format of RBM is its random weight initialization which leads to improper feature learning of the model during the training phase, resulting in poor performance of the machine. This problem has been tried to eliminate in this work by finding the differences between the means of a specific feature vector and the means of all features given as inputs to the machine. By performing this process, the reconstruction of the actual features is increased which ultimately reduces the error generated during the training phase of the model. The developed model has been applied to three different datasets of pneumonia diseases and the results have been compared with other state of the art techniques using different performance evaluation parameters. The proposed model gave highest accuracy of 98.56% followed by standard RBM, SVM, KNN, and decision tree which gave accuracies of 97.53%, 92.62%, 91.64%, and 88.77%, respectively, for dataset named dataset 2. Similarly, for the dataset 1, the highest accuracy of 96.66 has been observed for the eRBM followed by srRBM, KNN, decision tree, and SVM which gave accuracies of 90.22%, 89.34%, 87.65%, and 86.55%, respectively. In the same way, the accuracies observed for the dataset 3 by eRBM, standard RBM, KNN, decision tree, and SVM are 92.45%, 90.98%, 87.54%, 85.49%, and 84.54%, respectively. Similar observations can also be seen for other performance parameters showing the efficiency of the proposed model. As revealed in the results obtained, a significant improvement has been observed in the working of the RBM by introducing a new method of weight initialization during the training phase. The results show that the improved model outperforms other models in terms of different performance evaluation parameters, namely, accuracy, sensitivity, specificity, F1-score, and ROC curve.


Asunto(s)
Aprendizaje Automático , Neumonía , Algoritmos , Humanos , Neumonía/diagnóstico por imagen , Curva ROC , Rayos X
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