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1.
Chem Biodivers ; 21(6): e202400348, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38616166

RESUMEN

The immobilization of proteins on the surface of carriers is challenging due to the loss of protein structure and function in this process. Here, we report the development of the protein immobilization on the surface of the metallated-porphyrin complex in the porphysome nanocarrier. The conjugated Ni-porphyrin to fatty acid (as a tail) has been synthesized and independently placed at the depth of the bilayer center of Dipalmitoylphosphatidylcholine (DPPC) in which the Ni-porphyrin was at the polar region of the membrane and is thus superficial. This porphysome (DPPC: Ni-porphyrin, 4 : 1 mole ratio) was formed by supramolecular self-assembly with a diameter of 173±7 nm and zeta potential -8.5±3.4 mv, which exhibited no significant toxicity at the experimental concentrations and acceptable cellular uptake on MCF-7 cells. The physicochemical properties and specific protein binding sites of the firefly luciferase as a model protein into the porphysome (1 : 2 mole ratio) show the conjugation efficiency about 80 % and the conformation of protein was completely maintained. Furthermore, bioluminescence assay and SDS-PAGE confirmed the preservation of protein function. The stabilized platform of porphyrin-lipid structure can potentially improve the efficacy of protein functionality for a particular display, shifting porphysomes from a simple carrier to a therapeutic agent.


Asunto(s)
Porfirinas , Humanos , Sitios de Unión/efectos de los fármacos , Porfirinas/química , Porfirinas/farmacología , Células MCF-7 , Portadores de Fármacos/química , Nanomedicina Teranóstica , Nanopartículas/química , Supervivencia Celular/efectos de los fármacos , 1,2-Dipalmitoilfosfatidilcolina/química , Sistemas de Liberación de Medicamentos , Tamaño de la Partícula
2.
J Pharm Sci ; 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38582281

RESUMEN

The oral formulation design for colon-specific drug delivery brings some therapeutic benefits in the ulcerative colitis treatment. We recently reported the specific delivery of hemoglobin nanoparticles-conjugating 5-aminosalicylic acid (5-ASA-HbNPs) to the inflamed site. In the current study, the therapeutic effect of the 5-ASA-HbNPs formulation was confirmed in vivo. This evaluation of 5-ASA-HbNPs not only shows longer colonic retention time due to adhesive properties, also provides full support for it as compared with free 5-ASA. It was considered as a suitable bio-adhesive nanoparticle with mucoadhesive property to pass through the mucus layer and accumulate into the mucosa. In UC model mice, a two-fold decrease in the disease activity indexes and colon weight/length ratios was significantly observed in the group treated with 5-ASA-HbNPs. This group received one percent of the standard dosage of 5-ASA (50 µg/kg), while, a similar result was observed for a significant amount of free 5-ASA (5 mg/kg). Furthermore, microscopic images of histological sections of the extracted colons demonstrated that the 5-ASA-HbNPs and 5-ASA groups displayed instances of inflammatory damage within the colon. However, in comparison to the colitis group, the extent of this damage was relatively moderate, suggesting 5-ASA-HbNPs improved therapeutic efficacy with the lower dosage form.

3.
J Liposome Res ; 34(3): 475-488, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38252419

RESUMEN

'Active targeting' refers to modifying a nanocarrier's surface with targeting ligands. This study introduced an efficient approach for immobilizing imidazole-based drugs onto the metallated-porphyrin complex within the porphysome nanocarrier. To enhance cellular and bacterial uptake, a Ni-porphyrin with a fatty acid tail was synthesized and placed in the bilayer center of DPPC, facilitating receptor-mediated endocytosis. The Ni-porphyrin in the head group of the Ni-porphyrin-tail was placed superficially in the polar region of the membrane. Spherical unilamellar vesicle formation (DPPC: Ni-porphyrin-tail 4:1 mole ratio), as metallo-porphysome, was achieved through supramolecular self-assembly in an aqueous buffer. These vesicles exhibited a diameter of 279 ± 7 nm and a zeta potential of -15.3 ± 2.5 mV, showcasing their unique cytocompatibility. Nitroimidazole was decorated on the surface of metallo-porphysomes and pistachio green hull extract (PGHE) was loaded into the carrier for synergistic activity against (E. coli) and (S. aureus) bacteria strains. The physicochemical properties of Nitroimidazole-porphysome-PGHE, including size, zeta potential, morphology, loading efficiency, and release profile under various pH and temperature conditions in simulated gastrointestinal fluids were characterized. This combination therapy prevented bacterial cell attachment and biofilm formation in Caco-2 cells, as colon epithelial cells. The remarkable benefit of this system is that it does not affect cell viability even at 0.5 mg/ml. This study demonstrates the potential of a new co-delivery system using biocompatible metallo-porphysomes to decrease bacterial infections.


Asunto(s)
Antibacterianos , Escherichia coli , Pruebas de Sensibilidad Microbiana , Pistacia , Extractos Vegetales , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química , Humanos , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Pistacia/química , Porfirinas/química , Porfirinas/farmacología , Imidazoles/química , Imidazoles/farmacología , Tamaño de la Partícula , Portadores de Fármacos/química , Sinergismo Farmacológico , Células CACO-2
4.
Int J Biol Macromol ; 253(Pt 7): 127454, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37844822

RESUMEN

Glucosamine (Glu) is a cartilage and joint fluid matrix precursor that modulates osteoarthritic joint changes. To improve the enzymatic stability, glucosamine was developed into nanoglucosamine by the ionic gelation method through sodium tripolyphosphate (TPP) as cross-linking agent. The optimized mass ratio of Glu:TPP was (3:1) with the particle size 163 ± 25 nm and surface charge -5 mV. Then Sinapic acid (SA) as a natural phenolic acid with strong antioxidant and antimicrobial activities has been grafted onto glucosamine nanoparticles (GluNPs) with grafting efficiency (73 ± 6 %). The covalent insertion of SA was confirmed by UV-Vis, FTIR, 1HNMR, XRD, and FESEM analyses and the other physicochemical properties were also characterized. SA-g-GluNPs showed spherical shape with a mean diameter of 255 ± 20 nm and zeta potential +16 mV. The in vitro release profile of SA-g-GluNPs exhibited the sustained and pH-dependent drug release property. SA-g-GluNPs had a more pronounced effect on reducing the elevated levels of LPS-induced oxidative stress and pro-inflammatory cytokines than free SA in the human chondrocyte C28/I2 cell line. Furthermore, the antibacterial properties against E. coli and S. aureus were also improved by SA-g-GluNPs. This study demonstrated the potential of phenolic acid grafted GluNPs in therapeutic drug applications for chondroprotection and food industries.


Asunto(s)
Quitosano , Nanopartículas , Osteoartritis , Humanos , Glucosamina , Quitosano/química , Escherichia coli , Staphylococcus aureus , Antiinflamatorios/farmacología , Osteoartritis/tratamiento farmacológico , Nanopartículas/química
5.
J Pharm Biomed Anal ; 212: 114628, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35151068

RESUMEN

This review discusses recent advances and the reported strategies over the last ten years on the use of carbon-based quantum dots (QDs), including carbon dots (CDs), graphene quantum dots (GQDs), and polymer dots (PDs) in the design of fluorescence imaging and biosensing system for early diagnosis of cancers. Besides, this study comprehensively reports the latest developments in these years in the fluorescence imaging (FI) area with special attention to carbon-based QDs that take advantage of the excellent properties offered by these zero-dimensional (0D) nanomaterials as fluorescent tags. The most remarkable advantages of these carbon nanomaterials in the development of fluorescence sensing and imaging strategies compared to the conventional dyes arise from sharp emission spectra, long photostability, low-cost synthesis, reliability, reproducibility, high fluorescent intensity, and high surface functional groups such as carboxyl and amide, which impart better solubility in many solvents and aqueous media and facilitate their easy functionalization with biological species. The final section discusses the main challenges to be met to take full advantage of these properties in fluorescence bio-sensing and imaging as well as the possible future trends in this field based on the great advances that have occurred in recent years.


Asunto(s)
Técnicas Biosensibles , Neoplasias , Puntos Cuánticos , Técnicas Biosensibles/métodos , Carbono , Detección Precoz del Cáncer , Colorantes Fluorescentes , Humanos , Neoplasias/diagnóstico por imagen , Reproducibilidad de los Resultados
6.
Int J Pharm ; 616: 121531, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35121044

RESUMEN

A colonic drug delivery system was developed to specifically deliver 5-aminosalicylic acid (5-ASA) to the inflamed site by conjugating with hemoglobin nanoparticles (HbNPs). The 5-ASA-HbNPs (eight 5-ASA molecules per Hb molecule) with the size of 220 nm and zeta potential of -14.6 mV is a tailored nanoparticle able to pass through the mucus layer. The 5-ASA-HbNPs do not undergo chemical and enzymatic hydrolysis in the simulated gastrointestinal fluids over 6 h. Significantly higher cellular uptakes and prolonged release was seen for the 5-ASA-HbNPs in Caco-2 cells, compared to free 5-ASA over 72 h. In addition, 5-ASA-HbNPs revealed similar therapeutic effectiveness with free 5-ASA against tumor necrosis factor and showed less inhibitory concentration (IC50) for myeloperoxidase enzyme activity. In vivo imaging of mouse demonstrated the localization of drug in the descending colon after oral administration and about 15% of the administered dose was recovered as 5-ASA from urine in 6 h. The use of these nanoparticles with the mucus adhesion properties and permeability to intestinal epithelial cells can be a good candidate with potential application in the colonic drug delivery field.


Asunto(s)
Colitis Ulcerosa , Enfermedades Inflamatorias del Intestino , Nanopartículas , Adhesivos/farmacología , Animales , Antiinflamatorios no Esteroideos/química , Células CACO-2 , Colitis Ulcerosa/tratamiento farmacológico , Colon , Preparaciones de Acción Retardada/farmacología , Hemoglobinas , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Mesalamina , Ratones
7.
Chimia (Aarau) ; 76(7-8): 661-668, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-38071633

RESUMEN

Circulating tumor cells (CTCs), secreted from primary and metastatic malignancies, hold a wealth of essential diagnostic and prognostic data for multiple cancers. Significantly, the information contained within these cells may hold the key to understanding cancer metastasis, both individually and fundamentally. Accordingly, developing ways to identify, isolate and interrogate CTCs plays an essential role in modern cancer research. Unfortunately, CTCs are typically present in the blood in vanishingly low titers and mixed with other blood components, making their isolation and analysis extremely challenging. Herein, we report the design, fabrication and optimization of a microfluidic device capable of automatically isolating CTCs from whole blood. This is achieved in two steps, via the passive viscoelastic separation of CTCs and white blood cells (WBCs) from red blood cells (RBCs), and subsequent active magnetophoretic separation of CTCs from WBCs. We detail the specific geometries required to balance the elastic and inertial forces required for successful passive separation of RBCs, and the use of computational fluid dynamics (CFD) to optimize active magnetophoretic separation. We subsequently describe the use of magnetic biosilica frustules, extracted from Chaetoceros sp. diatoms, to fluorescently tag CTCs and facilitate magnetic isolation. Finally, we use our microfluidic platform to separate HepG2-derived CTCs from whole blood, demonstrating exceptional CTC recovery (94.6%) and purity (89.7%).

8.
J Biomater Sci Polym Ed ; 33(2): 174-196, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34605363

RESUMEN

Pseudomonas aeruginosa is the most common pathogen that causes chronic lung infections and recurrence of the disease in cystic fibrosis patients by hiding inside cells and biofilm matrix. Herein, we developed gentamicin and curcumin-loaded lipid-polymer hybrid nanoparticle- (termed CG-HNPs) to evaluate in vitro activities against biofilm-embedded P. aeruginosa and compared with lipid nanoparticles containing the same drugs (CG-Lip). The nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), fluorescence spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy, which demonstrated that HNPs with a diameter of approximately 340 nm were uniform. The optimal CG-HNPs formulation illustrated high encapsulation (∼70%) and controlled release characteristics (gradually released in 72 h). The antibacterial activities of generated nanoparticles are maintained against planktonic and biofilm bacteria and it is effective in damage established biofilms. Besides, HNPs were biocompatible and nontoxic to J774 and HFF cell lines and uptake by the macrophages (J774), which facilitated the killing of intracellular bacteria in macrophages. These results introduced CG-HNPs as a promising antibacterial agent for the treatment of chronic infections and intracellular bacteria due to excellent antibacterial activity.


Asunto(s)
Curcumina , Nanopartículas , Antibacterianos/farmacología , Biopelículas , Curcumina/farmacología , Gentamicinas/farmacología , Humanos , Lípidos , Liposomas , Pruebas de Sensibilidad Microbiana , Infección Persistente , Polímeros , Pseudomonas aeruginosa
9.
Med J Islam Repub Iran ; 36: 171, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36896240

RESUMEN

Background: Mental disorders have a high prevalence and significant burden among all health conditions across the world and in Iran. Therefore, some targets in the field of mental health and substance and alcohol use prevention have been included in the National Action Plan for Prevention and Control of Non-communicable Diseases and Related Risk Factors. Methods: Keeping in mind the key priorities, important strategies have been considered for attaining the main targets in this field. These strategies fall under four categories of governance, prevention and reduction of risk factors, health care, and surveillance, and monitoring and evaluation strategies. Conclusion: The success of mental health and substance and alcohol use prevention programs in Iran can be partly related to the evidence-based approach adopted and also to the commitment of high-rank officials of the Ministry of Health and Medical Education to the principal strategy of increasing access to the general population to basic mental health services, among all other non-communicable diseases.

10.
Cureus ; 12(8): e9889, 2020 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-32968555

RESUMEN

A 44-year-old male without any significant past medical history presented to the emergency department (ED) with the chief complaint of severe constant epigastric pain for three hours. On physical examination, the abdomen was distended and tender, particularly in the epigastric region. The lab work showed an elevation of the lipase (12,405 U/L) and triglycerides (5,837 mg/dL). An abdominal CT scan with contrast was ordered, which revealed non-necrotic pancreatitis. In addition, the liver ultrasound showed no evidence of gallstones. Subsequently, fluid infusion, meropenem, pain medication, and an insulin drip were started, and the patient was transferred to the intensive care unit (ICU). After six hours in the ICU, he complained of abdominal pain despite taking a high hydromorphone dose. On further physical examination, the abdomen was tender and distended but without rebound tenderness. The gastric distention on kidneys, ureter, and bladder (KUB) and a bladder pressure of 34 mmHg raised the suspicion for intra-abdominal hypertension (IAH), which led us to place a nasogastric tube (NGT) and consult the surgical team. The patient's symptoms and bladder pressure were closely followed and showed significant improvement. On day seven in the ICU, the patient responded well to medications; feeding through the Dobhoff tube was started, and his triglycerides decreased to approximately 1,000 mg/dL. Despite his general improvement and meropenem regimen, the patient spiked a fever of 38.5 °C. Due to the possibility of pancreatitis complications, a CT abdomen with contrast was ordered, which showed partial portal vein thrombosis (PVT). Subsequently, enoxaparin was started, and the patient was closely observed for gastrointestinal bleeding. Eventually, after 17 days in the ICU, the patient was transferred to the floor and then discharged from the hospital with normal lab tests and without evidence of portal thrombosis on abdominal CT. In this report, we illustrate and discuss a case of hypertriglyceridemia (HTG)-induced pancreatitis (HTGP), which progressed to PVT and IAH. Physicians should be aware that patients with HTG are inclined to have severe pancreatitis. In addition, the degree of triglyceride elevation is correlated with the severity of acute pancreatitis.

11.
Cureus ; 12(8): e9684, 2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32923277

RESUMEN

Allergic bronchopulmonary aspergillosis (ABPA) is an eosinophilic pulmonary disorder caused by a hypersensitivity reaction to Aspergillus fumigatus that manifests with uncontrolled asthma, peripheral blood eosinophilia, and radiological findings, such as mucus plugging. Early diagnosis and proper treatment of ABPA are essential to prevent irreversible lung damage such as pulmonary fibrosis and bronchiectasis and improve the quality of life of patients. Beside inhaled medication for asthma, anti-inflammatory agents (i.e., systemic glucocorticoids) and antifungal agents are the mainstay treatment of ABPA. The goal of therapy using glucocorticoids and antifungal agents is to suppress the immune hyperreactivity to A. fumigatus and attenuate the fungal burden. Since the systemic glucocorticoid therapy may lead to serious adverse effects including osteoporosis, avascular necrosis, myopathy, cushingoid appearance, hypertension, insomnia, and increased risk of infection, a glucocorticoid-sparing agent could be considered. Mepolizumab is a humanized monoclonal antibody that binds to interleukin-5, which is the key mediator for eosinophil differentiation, activation, migration, and survival. We review eight cases of ABPA treated successfully with mepolizumab. Treatment with mepolizumab was not restricted to the total immunoglobulin E level, the limiting factor for omalizumab in ABPA. In addition, mepolizumab therapy improved forced expiratory volume in one second, radiological findings, and patient quality of life.

12.
Gastroenterol Hepatol Bed Bench ; 13(3): 268-271, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32821359

RESUMEN

Angiosarcomas are soft-tissue neoplasms that originate from the vascular epithelium. The most commonly involved sites include the skin and subcutaneous tissues. In the GI tract, generally, angiosarcomas involve the spleen and liver, although locations in the small intestine and colon have been very occasionally reported. In the present study we report the unusual case of a man with duodenal epithelioid angiosarcoma, presenting with anemia and recurrent upper gastrointestinal bleeding, which was initially misdiagnosed as a Dieulafoy's lesion. It is important to consider the diagnosis of gastrointestinal malignancy, including unusual neoplasms such as angiosarcomas, in the setting of anendoscopic appearance such as hemorrhagic nodule, purpuric mass and/or recurrent bleeding lesions that are persistent despite repeat interventions. In such cases, a biopsy should be considered to confirm the diagnosis.

13.
Talanta ; 218: 121137, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32797894

RESUMEN

A new method based on fluorescent probe of iron quantum cluster has been proposed for rapid detection of Escherichia coli (E. coli). The iron quantum cluster was synthesized using hemoglobin as both a source of iron and a protective agent (Hb-FeQCs). The investigation of the sensitivity of Hb-FeQCs towards metal ions showed a highly selective turn off fluorescence for Cu2+. It suggests that Cu2+ can induce fluorescence quenching by binding to amino acids of Hb. The ability of E. coli bacteria to capture and reduce of Cu ions caused to efficient recovery of the fluorescence of Hb-FeQCs from Cu2+-caused quenching. This probe has a satisfactorily linear range of 0.35-35 µM for Cu2+ under the optimal iron quantum cluster concentration (500 µg/mL) with an 85 nM detection limit. Rapid and facile detection of E.coli bacteria with the limit of detection around 8.3 × 103 CFU/mL was successfully achieved in the artificially contaminated urine, tap water, and DMEM samples within 30 min. The fluorescence recovery was investigated by different types of bacteria and only E. coli revealed 56% recovery which related to its capability to Cu2+ reduction and the great potential of the fluorescent probe for rapid detection of pathogenic E. coli bacteria. Furthermore, the Hb-FeQCs can detect E. coli bacteria in an infected urine sample by retrieving up to 74% of its fluorescence which is helpful to accelerate the diagnosis and treatment of urinary tract infection (UTI).


Asunto(s)
Hierro , Puntos Cuánticos , Cobre , Escherichia coli , Colorantes Fluorescentes , Hemoglobina Falciforme , Límite de Detección , Espectrometría de Fluorescencia
14.
Pharm Dev Technol ; 25(9): 1150-1161, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32746669

RESUMEN

Imidazolium-based ionic liquid functionalized PEGylated mesoporous silica nanoparticles MCM-41 (denoted as [ImIL-PEGylated@MCM-41] NPs) is synthesized and evaluated as an efficient and reliable pH-sensitive nano-carrier for controlled release of cationic Lapatinib (Lap) drug. This nano-DDS was fully characterized by dynamic light scattering, scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, N2 adsorption-desorption measurement, and differential scanning calorimeter. Furthermore, the drug loading content and in-vitro drug release profile were studied. The entrapment and loading efficiency of the optimized formulation for Lap were 91 ± 2.0% and 32.21 ± 2.70%, respectively. The results of cytotoxicity assay demonstrated that ImIL-PEG@MCM-41 has no significant toxicity on both cancerous and normal cell lines and the anticancer activity of Lap@ImIL-PEG@MCM-41 was comparable to free drug in case of human breast cells (SKBR3) and human embryonic kidney 293 cells (HEK-293). Meanwhile, three-dimensional (3D) cell culture was performed by multicellular tumor spheroids for understanding of cell response to drugs in physiologically 3D microenvironments. The results of Lap@ImIL-PEG@MCM-41 uptake during 48 hours showed a gradual release of the Lap through the multicellular tumor spheroids. This showed that the pH-responsive controlled release of Lapatinib leads to the satisfactory results in the in vitro breast cancer therapy.


Asunto(s)
Portadores de Fármacos/química , Imidazoles/química , Líquidos Iónicos/química , Lapatinib/química , Nanopartículas/química , Dióxido de Silicio/química , Adsorción , Línea Celular , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de los fármacos , Dispersión Dinámica de Luz/métodos , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo/métodos , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X/métodos
15.
Photodiagnosis Photodyn Ther ; 30: 101753, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32305652

RESUMEN

The ability to identify and enrich target cells can play a significant role in biosensing in general. For the separation of rare cells; a biosilica structure was extracted from "Chaetoceros sp." diatoms as a novel natural source of mesoporous materials. These diatoms had special optical capabilities, especially in fluorescence emission. Biosilica surfaces of Chaetoceros sp. were chemically modified by iron oxide nanoparticles resulting in diatom silica magnetic particles functionalized with Trastuzumab antibody to separate the breast cancer cells from normal cells. The fully characterization of magnetic biosilica structure were studied by various spectroscopic techniques. The magnetic diatom conjugated with antibody displays strong absorption and two main types of fluorescence emission with peaks centered at 493 and 650 nm (photo-excited at 405 nm). As in vitro study, SKBR3 cells (HER2 positive cells) were selectively targeted and separated with this magnetic diatom structure from the mix of HER2 negative cells using a magnetic field. These results show that Chaetoceros silica shells are promising eco-friendly biomaterials suitable for biosensing chip and the targeted delivery of drugs to the specific sites.


Asunto(s)
Diatomeas , Neoplasias , Fotoquimioterapia , Fluorescencia , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes , Dióxido de Silicio
16.
Mater Sci Eng C Mater Biol Appl ; 111: 110775, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32279758

RESUMEN

Template-mediated self-assembly synthesis has produced a diverse range of biomimetic materials with unique physicochemical properties. Here, we fabricated novel fluorescent three-dimensional (3-D) hydroxyapatite (HAP) nanorod-assembled microspheres using iron quantum cluster (FeQC) as a hybrid template, containing three organic components: hemoglobin chains, piperidine, and iron clusters. The material characterization indicated that the synthesized HAP possessed a uniform rod-like morphology, ordered 3-D architecture, high crystallinity, self-activated fluorescence, and remarkable photostability. Our study proposed that this FeQC template is a promising regulating agent to fabricate fluorescent self-assembled HAP microspheres with a controlled morphology. The effect of HAP on stem cell fate and their osteogenic differentiation was investigated by culturing human bone marrow-derived mesenchymal stromal/stem cells (BMSCs) with HAP microspheres. Significant increases in collagen matrix production and gene expression of osteogenic markers, including osteocalcin (OCN), Runt-related transcription factor 2 (Runx2), bone sialoprotein (BSP) and alkaline phosphatase (ALP), were observed compared to the controls after 21 days of culture. Taken together, our data suggest that synthetic HAP nanorod-assembled microspheres represent a promising new biomaterial which exhibits enhanced fluorescent properties and osteoinductive effects on human BMSCs.


Asunto(s)
Materiales Biocompatibles/química , Durapatita/química , Hierro/química , Puntos Cuánticos/química , Fosfatasa Alcalina/metabolismo , Materiales Biocompatibles/farmacología , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colágeno/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Colorantes Fluorescentes/química , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Microesferas , Osteocalcina/metabolismo , Osteogénesis/efectos de los fármacos
17.
Nanomaterials (Basel) ; 10(4)2020 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-32252384

RESUMEN

Microfluidics cell-based assays require strong cell-substrate adhesion for cell viability, proliferation, and differentiation. The intrinsic properties of PDMS, a commonly used polymer in microfluidics systems, regarding cell-substrate interactions have limited its application for microfluidics cell-based assays. Various attempts by previous researchers, such as chemical modification, plasma-treatment, and protein-coating of PDMS revealed some improvements. These strategies are often reversible, time-consuming, short-lived with either cell aggregates formation, not cost-effective as well as not user- and eco-friendly too. To address these challenges, cell-surface interaction has been tuned by the modification of PDMS doped with different biocompatible nanomaterials. Gold nanowires (AuNWs), superparamagnetic iron oxide nanoparticles (SPIONs), graphene oxide sheets (GO), and graphene quantum dot (GQD) have already been coupled to PDMS as an alternative biomaterial enabling easy and straightforward integration during microfluidic fabrication. The synthesized nanoparticles were characterized by corresponding methods. Physical cues of the nanostructured substrates such as Young's modulus, surface roughness, and nanotopology have been carried out using atomic force microscopy (AFM). Initial biocompatibility assessment of the nanocomposites using human amniotic mesenchymal stem cells (hAMSCs) showed comparable cell viabilities among all nanostructured PDMS composites. Finally, osteogenic stem cell differentiation demonstrated an improved differentiation rate inside microfluidic devices. The results revealed that the presence of nanomaterials affected a 5- to 10-fold increase in surface roughness. In addition, the results showed enhancement of cell proliferation from 30% (pristine PDMS) to 85% (nano-modified scaffolds containing AuNWs and SPIONs), calcification from 60% (pristine PDMS) to 95% (PDMS/AuNWs), and cell surface marker expression from 40% in PDMS to 77% in SPION- and AuNWs-PDMS scaffolds at 14 day. Our results suggest that nanostructured composites have a very high potential for stem cell studies and future therapies.

18.
Gastroenterol Hepatol Bed Bench ; 13(2): 184-187, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32308943

RESUMEN

The most common sites of metastasis for esophageal cancers include the liver, lungs, and bones. We report a rare case of esophageal adenocarcinoma with metastasis to the subcutaneous perianal region as well as to the small bowel. Physicians should consider the possibility of metastasis in a patient with esophageal adenocarcinoma even after the onset of remission. It is essential to examine these patients and maintain a high index of suspicion for possible metastases. Early recognition helps in the accurate staging of the disease and enables the initiation of life-prolonging therapy and achieving meaningful palliation.

19.
Case Rep Gastroenterol ; 14(1): 15-26, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32095121

RESUMEN

The primary purpose of screening colonoscopy is the detection and subsequent removal of precancerous polyps. However, effective recognition of appendiceal lesions with a standard endoscope is often challenging and is limited to the base of the cecum and appendiceal orifice. The majority of appendiceal polyps are found incidentally following an appendectomy, though rarely they may be discovered during a colonoscopy. Despite being visualized by colonoscopy, most of these polyps are generally referred for surgical resection. The risk of developing carcinoma in patients with appendiceal polyps is likely similar to that of other colonic polyps, so it is essential for the endoscopist to examine and visualize the appendiceal orifice thoroughly. Various techniques are available to the endoscopist that can increase the accuracy of colonoscopic evaluation. These include luminal inflation and deflation, looking behind and pressing haustral folds, and repetitive passage of the scope over poorly visualized areas. To our knowledge, only 3 cases have been reported in the literature describing the discovery of obscure appendiceal polyps using colonoscopic techniques. Here we describe three cases of appendiceal orifice polyps missed on initial visualization but subsequently protruded into the cecum following prolonged examination and gentle deflation in the cecum. The endoscopist should consider the possibility of an appendiceal neoplasm, especially if other colonic polyps have been found. Endoscopists should spend adequate time examining the cecum during a screening colonoscopy to expose and thoroughly examine the appendiceal region.

20.
Colloids Surf B Biointerfaces ; 185: 110552, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31648117

RESUMEN

The endostatin protein is a potent inhibitor of angiogenesis and tumor growth. The anti-angiogenic and antitumor properties of full-length endostatin can be mimicked by its N-terminal segment, including residues 1-27. Therefore, our previous studies have shown that a mutant N-terminal peptide which the Zn-binding loop was replaced by a disulfide loop (referred to as the ES-SS peptide) has preserved antiangiogenic and antitumor properties compared to the native peptide. To increase stability and plasma half-life of the ES-SS peptide, the nano-sized liposomal formulations of the peptide with different ratio of phosphocholine (PC) were synthesized. The liposomal peptide formulations possessed an average size of around 100 nm with (-4 to -36 mv) in zeta potential. The encapsulation efficiency of the ES-SS peptide was in the range of 24-54% with different lipid: peptide molar ratios. In vitro release of the peptide from liposomes indicated a complete peptide release after 7 days. Cytotoxicity assay was evaluated using the human umbilical vein endothelial cells (HUVECs) for various concentrations of the liposomal peptide. The results depicted the gradual release of the peptide through liposomes. By comparing with the free peptide, the liposomal peptide formulations have indicated higher cell viability with IC50 value about 0.1 µM. The peptide-liposome interactions, as well as the peptide effect on the liposome structure, were also investigated through coarse-grained molecular dynamics (CG-MD) simulation. The results revealed that the peptides were assembled in the hydrophilic core of the liposome. The peptide behavior in liposome can stabilize the liposome structure and be a response to the observed low peptide release rate. The investigation is promising for designing a liposome-based anti-angiogenesis peptide delivery system.


Asunto(s)
Liberación de Fármacos , Endostatinas/metabolismo , Péptidos/metabolismo , Muerte Celular , Supervivencia Celular , Células Endoteliales de la Vena Umbilical Humana/citología , Humanos , Liposomas , Simulación de Dinámica Molecular
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