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1.
Nanomaterials (Basel) ; 14(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38786780

RESUMO

Understanding both the physicochemical and biological interactions of nanoparticles is mandatory for the biomedical application of nanomaterials. By binding proteins, nanoparticles acquire new surface identities in biological fluids, the protein corona. Various studies have revealed the dynamic structure and nano-bio interactions of the protein corona. The binding of proteins not only imparts new surface identities to nanoparticles in biological fluids but also significantly influences their bioactivity, stability, and targeting specificity. Interestingly, recent endeavors have been undertaken to harness the potential of the protein corona instead of evading its presence. Exploitation of this 'protein-nanoparticle alliance' has significant potential to change the field of nanomedicine. Here, we present a thorough examination of the latest research on protein corona, encompassing its formation, dynamics, recent developments, and diverse bioapplications. Furthermore, we also aim to explore the interactions at the nano-bio interface, paving the way for innovative strategies to advance the application potential of the protein corona. By addressing challenges and promises in controlling protein corona formation, this review provides insights into the evolving landscape of the 'protein-nanoparticle alliance' and highlights emerging.

2.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791209

RESUMO

Nanoparticles (NPs) are extremely important tools to overcome the limitations imposed by therapeutic agents and effectively overcome biological barriers. Smart designed/tuned nanostructures can be extremely effective for cancer treatment. The selection and design of nanostructures and the adjustment of size and surface properties are extremely important, especially for some precision treatments and drug delivery (DD). By designing specific methods, an important era can be opened in the biomedical field for personalized and precise treatment. Here, we focus on advances in the selection and design of nanostructures, as well as on how the structure and shape, size, charge, and surface properties of nanostructures in biological fluids (BFs) can be affected. We discussed the applications of specialized nanostructures in the therapy of head and neck cancer (HNC), which is a difficult and aggressive type of cancer to treat, to give an impetus for novel treatment approaches in this field. We also comprehensively touched on the shortcomings, current trends, and future perspectives when using nanostructures in the treatment of cancer.


Assuntos
Nanoestruturas , Humanos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Antineoplásicos/administração & dosagem , Nanopartículas/química , Nanopartículas/uso terapêutico , Animais
3.
J Pharm Biomed Anal ; 226: 115250, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36657352

RESUMO

In this study, a L-asparagine (L-Asn) imprinted membranes (L-Asn-MIPs) were synthesized via molecular imprinting for selective and efficient removal of L-Asn. The L-Asn-MIP membrane was prepared by using acrylamide (AAm) and hydroxyethyl methacrylate (HEMA) as a functional monomer and a comonomer, respectively. The membrane was characterized by scanning electron microscopy (SEM) and Fourier Transform infrared spectroscopy (FTIR). The L-Asn adsorption capacity of the membrane was investigated in detail. The maximum L-Asn adsorption capacity was determined as 408.2 mg/g at pH: 7.2, 24 °C. Determination of L-Asn binding behaviors of L-Asn-MIPs also shown with Scatchard analyses. The effect of pH on L-Asn adsorption onto the membrane and also the selectivity and reusability of the L-Asn-MIPs for L-Asn adsorption were determined through L-asparaginase (L-ASNase) enzyme activity measurements. The selectivity of the membrane was investigated by using two different ternary mixtures; L-glycine (L-Gly)/L-histidine (L-His)/L-Asn and L-tyrosin (L-Tyr)/L-cystein(L-Cys)/L-Asn. The obtained results showed that the L-Asn-MIP membranes have a high selectivity towards L-Asn.


Assuntos
Asparagina , Impressão Molecular , Adsorção , Microscopia Eletrônica de Varredura , Impressão Molecular/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Colloids Surf B Biointerfaces ; 222: 113031, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36435026

RESUMO

Short peptides are important in the design of self-assembled materials due to their versatility and flexibility. Self-assembled dipeptides, a group of peptide nanostructures, have highly attractive uses in the field of biomedicine. Recently these materials have proved to be important nanostructures because of their biocompatibility, low-cost and simplicity of synthesis, functionality/easy tunability and nano dimensions. Although there are different studies on peptide and protein-based nanostructures, more information about self-assembled nanostructures for dipeptides is still required to discover the advantages, challenges, importance, synthesis, interactions, and applications. This review describes and discusses the self-assembled dipeptide nanostructures especially for biomedical applications.


Assuntos
Dipeptídeos , Nanoestruturas , Dipeptídeos/química , Peptídeos/química , Nanoestruturas/química
5.
Colloids Surf B Biointerfaces ; 221: 113024, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36403418

RESUMO

Microbial adhesion and formation of biofilms cause a serious problem in several areas including but not limited to food spoilage, industrial corrosion and nosocomial infections. These microbial biofilms pose a serious threat to human health since microbial communities in the biofilm matrix are protected with exopolymeric substances and difficult to eradicate with antibiotics. Hence, the prevention of microbial adhesion followed by biofilm formation is one of the promising strategies to prevent these consequences. The attachment of antimicrobial agents, coatings of nanomaterials and synthesis of hybrid materials are widely used approach to develop surfaces having potential to hinder bacterial adhesion and biofilm formation. In this study, epigallocatechin gallate (EGCG) is attached on p(HEMA-co-GMA) membranes to prevent the bacterial colonization. The attachment of EGCG to membranes was proved by Fourier-transform infrared spectroscopy (FT-IR). The synthesized membrane showed porous structure (SEM), and desirable swelling degree, which are ideal when it comes to the application in biotechnology and biomedicine. Furthermore, EGCG attached membrane showed significant potential to prevent the microbial colonization on the surface. The obtained results suggest that EGCG attached polymer could be used as an alternative approach to prevent the microbial colonization on the biomedical surfaces, food processing equipment as well as development of microbial resistant food packaging systems.


Assuntos
Aderência Bacteriana , Biofilmes , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros
6.
Food Chem ; 372: 131254, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818729

RESUMO

Molecularly imprinted polymer based nanofilms specific to melamine were synthesized on quartz crystal microbalance (QCM) electrode surface. Contact angle measurements, atomic force microscopy, ellipsometry and scanning electron microscopy were used for characterizations process. Some of the findings of the study are as follows: pH 6.0 was found as optimal working pH for melamine detection. Prepared MIP QCM electrode showed a linearity of 99.53% in the concentration range of 50-1000 ng/mL. Langmuir-Freundlich hybrid model was the best fitted isotherm for whole concentration range. The performance of MIP QCM electrode was also confirmed by determining of melamine in melamine spiked milk samples. As a conclusion, the results figured out that not only QCM nanosensor for specific melamine detection but also polymerization strategy were classified as an intriguing alternative for developing new melamine sensing platforms. Limit of detection (LOD) and limit of quantification (LOQ) were calculated as 2.3 ng/mL and 7.8 ng/mL, respectively.


Assuntos
Impressão Molecular , Técnicas de Microbalança de Cristal de Quartzo , Animais , Eletrodos , Leite , Polímeros , Triazinas
7.
Arch Microbiol ; 203(7): 3739-3749, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34002253

RESUMO

Bacteria utilize small signal molecules to monitor population densities. Bacteria arrange gene regulation in a method called Quorum Sensing (QS). The most widespread signalling molecules are N-Acyl Homoserine Lactones (AHLs/HSLs) for Gram-negative bacteria communities. QS plays significant role in the organizing of the bacterial gene that adapts to harsh environmental conditions for bacteria. It is involved in the arrangement of duties, such as biofilm formation occurrence, virulence activity of bacteria, production of antibiotics, plasmid conjugal transfer incident, pigmentation phenomenon and production of exopolysaccharide (EPS). QS obviously impacts on human health, agriculture and environment. AHL-related QS researches have been extensively studied and understood in depth for cell to cell intercommunication channel in Gram-negative bacteria. It is understood that AHL-based QS research has been extensively studied for cell-to-cell communication in Gram-negative bacteria; hence, a comprehensive study of AHLs, which are bacterial signal molecules, is required. The purpose of this review is to examine the effects of QS-mediated AHLs in many areas by looking at them from a different perspectives, such as clinic samples, food industry, aquatic life and wastewater treatment system.


Assuntos
Acil-Butirolactonas , Bactérias Gram-Negativas , Percepção de Quorum , Acil-Butirolactonas/metabolismo , Bactérias Gram-Negativas/fisiologia , Humanos , Percepção de Quorum/fisiologia
8.
Appl Biochem Biotechnol ; 193(8): 2483-2496, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33779933

RESUMO

Stability of enzymes is a significant factor for their industrial feasibility. α-Amylase is an important enzyme for some industries, i.e., textile, food, paper, and pharmaceutics. Pumice particles (PPa) are non-toxic, natural, and low-cost alternative adsorbents with high adsorption capacity. In this study, Cu2+ ions were attached to pumice particles (Cu2+-APPa). Then, Cu2+-APPa embedded composite cryogel was synthesized (Cu2+-APPaC) via polymerization of gel-forming agents at minus temperatures. Characterization studies of the Cu2+-APPaC cryogel column were performed by X-ray fluorescence spectrometry (XRF), scanning electron microscopy (SEM), and Brunauer, Emmett, Teller (BET) method. The experiments were carried out in a continuous column system. α-Amylase was adsorbed onto Cu2+-APPaC cryogel with maximum amount of 858.7 mg/g particles at pH 4.0. Effects of pH and temperature on the activity profiles of the free and the immobilized α-amylase were investigated, and results indicate that immobilization did not alter the optimum pH and temperature values. kcat value of the immobilized α-amylase is higher than that of the free α-amylase while KM value increases by immobilization. Storage and operational stabilities of the free and the immobilized α-amylase were determined for 35 days and for 20 runs, respectively.


Assuntos
Criogéis/química , Enzimas Imobilizadas/química , alfa-Amilases/química , Cobre/química , Concentração de Íons de Hidrogênio
9.
Mater Sci Eng C Mater Biol Appl ; 113: 111020, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32487418

RESUMO

Selection of purification method and type of adsorbent has high significance for separation of a biomolecule like deoxyribonucleic acid (DNA). Nanoflowers are a newly improved class of adsorbent. Due to showing very structural similarity to plant flowers, they are named as nanoflowers. Herein, after synthesize of copper phosphate three hydrate nanoflowers [(Cu3(PO4)2.3H2O), CP-NFs], Fe3+ ions were attached to their surfaces. Obtained Fe3+-CP-NFs, before investigation of some adsorption parameters for DNA, they were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Some attained data from the results of adsorption experiments as follows: While maximum DNA adsorption on Fe3+-CP-NFs was found as an excellent value of 845.8 mg/g, nanoflowers without Fe3+ ions adsorbed DNA as only 25.3 mg/g. Optimum media conditions for DNA adsorption were observed at pH 7 and 25 °C with an initial concentration of 1.5 mg/mL DNA. Langmuir and Freundlich adsorption equations were applied to determine which adsorption model was appropriate, and it was seen that Langmuir model was fit with a R2 of 0.9885.


Assuntos
DNA/química , Imidazóis/química , Ferro/química , Nanoestruturas/química , Adsorção , Cobre/química , DNA/isolamento & purificação , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Fosfatos/química
10.
Environ Monit Assess ; 191(12): 722, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696322

RESUMO

Monitoring of groundwater is fundamentally important due to it has emerged as a major source of drinking water and also used for irrigation purposes in many places in the world. Arsenic contamination in surface water and groundwater resources is a major concern due to its presence at high concentration and associated adverse health effects. Thus, the remediation of As in water resources, alongside other chemical species including fluoride, lithium, vanadium aluminium and nitrate is necessary. We have designed a hybrid [polyethyleneimine (PEI)-supported Fe3+-attached poly-(HEMA-co-GMA)] column for the reduction of arsenic (III and V) and other groundwater chemicals from natural groundwater as a potential contribution to water resource management. Swelling behaviour and scanning electron microscopy (SEM) were performed for the characterization of hybrid material. For the optimization of experimental conditions, the effects of pH and initial arsenic concentrations on adsorption were studied using arsenic solutions. Maximum adsorption capacity in equilibrium was 11.44 and 5.79 mg/g polymer for As(III) and As(V), respectively at pH 7. The reduction of metalloids and other subsurface chemicals were carried out with natural groundwater samples obtained from local sources. The mean concentrations of arsenic were recorded between 44.96 and 219.04 µg/L and of which 71.3-95.4 % (0.32-1.22 mg/g) were removed. The average removals were determined as F-1 50-86%, Li+ 43.2-99.7%, Al+3 83.8-91.4%, NO3- 48.4-72.2% and V 91.3-95.7. Chemical-loaded hybrid columns were regenerated successfully 15 times with only a loss of 5% in adsorption capacity by 0.01 M NaCl- treatment for potential adaptation into water industry. No pre-oxidation of As species was performed for the treatment of ground water samples prior to the hybrid column testing.


Assuntos
Arsênio/análise , Filtração/métodos , Água Subterrânea/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Alumínio , Monitoramento Ambiental , Fluoretos , Água/química
11.
Int J Biol Macromol ; 141: 1183-1190, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31520707

RESUMO

Preparation of new sorbents specific to DNA has a great significance in many biomedical fields. This study reports a new sorbent with high surface area and porosity to immobilize nucleic acids having both high molecular weight like genomic DNA (gDNA) for potential use in therapy of some immune system disease and low molecular weight like plasmid DNA (pDNA) for diagnosis, gene therapy and DNA vaccination. For this aim, silica-based pore-expanded SBA-15 nanoparticles with aminopropyl-trimethoxysilane (APTMS) for decoration of Fe+3 ions (PE SBA-15-APTMS/Fe+3) were synthesized to get high surface area for high adsorption, and embedded into cryogel column for obtaining interconnected pores to avoid diffusion limitation of DNA samples because of their viscosity features. SEM, XRD, BET, and FTIR techniques were used for characterization of samples. Synthesized hybrid column showed a superior adsorption capacity of 751.5 mg/g NP for gDNA at pH 6 with an initial concentration of 2.0 mg/mL. Hybrid column presented excellent performance for pDNA when evaluated with agarose gel electrophoresis.


Assuntos
Cromatografia/métodos , DNA/química , Genômica , Plasmídeos/genética , Adsorção , Concentração de Íons de Hidrogênio , Isocianatos/química , Peso Molecular , Nanopartículas/química , Concentração Osmolar , Silanos/química , Dióxido de Silício/química , Temperatura
12.
Colloids Surf B Biointerfaces ; 182: 110354, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325775

RESUMO

Nanoflowers - new nanostructures - have aroused the interest of scientists due to the topographic features of nanolayers, the special location of which allows a higher surface-to-volume ratio compared to classic spherical nanoparticles, which significantly increases the efficiency of surface reactions for nanoflowers. The main purpose of these types of nanomaterials is their use as enzyme stabilizers. To facilitate the functioning of enzymes under different conditions, organic-inorganic hybrid nanomaterials have been developed, the name of which indicates that all components of inorganic nanoparticles are associated with organic materials. These nanoparticles have many promising applications in catalysis, as biosensors, and for drug delivery. Organic-inorganic hybrid nanoflowers have led to the development of a new branch of chemistry - the chemistry of hybrid nanomaterials - in which research is rapidly developing. Thus, studying organic-inorganic hybrid nanocrystals can lead to creative new solutions in the field of chemistry of enzyme systems and the rapid development of bionanomaterials and new biotechnology industries. Present review focuses on wide biomedical applications of nanoflowers including biocatalysis, detection of substances, electrochemical biosensors based on nanoflowers, photosensitizers, drug and gene carriers and detection of various diseases, photothermal and other treatments. It will be interesting for wide range of scientists focusing in topic of new kinds of nanoparticles.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas/síntese química , Nanomedicina/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Animais , Biocatálise , Sistemas de Liberação de Medicamentos/métodos , Técnicas Eletroquímicas , Humanos , Estruturas Metalorgânicas/ultraestrutura , Nanomedicina/instrumentação , Nanoestruturas/administração & dosagem , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Propriedades de Superfície
13.
Obes Surg ; 29(2): 729-734, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30542826

RESUMO

BACKGROUND: Morbidly obese patients are at high risk for developing venous thromboembolism (VTE). The aim of this study was to evaluate the effect of a new VTE prophylaxis protocol (low dosage, low-molecular-weight heparin [LMWH]) with a pneumatic compression device (PCD) in patients undergoing bariatric surgery. MATERIALS AND METHODS: Between November 2015 and December 2017, 368 patients underwent surgery due to obesity. The patients received 0.2 ml of nadroparin (Fraxiparine, GlaxoSmithKline) 12 h before the operation. A PCD (Kendall SCD Compression System) was applied to the patient during the operation and left on the patient during the subsequent 24 h. Nadroparin 0.4 ml was started subcutaneously after the PCD was removed from the patient and the same dosage of nadroparin was given daily for 15 days following the bariatric operation. Ambulation within 2 h of surgery was encouraged and was performed frequently. RESULTS: A total of 368 patients underwent laparoscopic bariatric surgery. The median age was 34.1 years (range, 18-61), the median weight was 128 kg (range, 90-182), and the median body mass index (BMI) was 47.2 kg/m2 (range, 36-72). No thrombotic events were observed postoperatively or at the 1-, 3-, and 6-month follow-up visits. Four bleedings occurred requiring transfusions. None of these patients required a re-laparotomy for hemorrhage control. The mortality rate was 0% at 30 and 90 days and during the hospitalization. CONCLUSION: Low dosage LMWH with PCD is very effective for VTE prophylaxis in bariatric surgery.


Assuntos
Anticoagulantes/uso terapêutico , Cirurgia Bariátrica , Dispositivos de Compressão Pneumática Intermitente , Nadroparina/uso terapêutico , Tromboembolia Venosa/prevenção & controle , Adolescente , Adulto , Transfusão de Sangue/estatística & dados numéricos , Protocolos Clínicos , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Assistência Perioperatória , Hemorragia Pós-Operatória/etiologia , Adulto Jovem
14.
Artif Cells Nanomed Biotechnol ; 46(sup3): S538-S545, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30299164

RESUMO

In order to investigate the biocatalytic properties of α-amylase on a composite cryogel matrix with immobilized metal affinity chromatography, Cu+2-attached poly(2-hydroxyethyl methacrylate) (Cu+2-PHEMA) beads, (2 µm size) were synthesized, then composite cryogel column was prepared by composing beads and PHEMA cryogels. After the preparation of Cu+2-PHEMA beads embedded cryogel column (Cu+2-BEC), some experiments were tested. Accordingly, the highest adsorption capacity (676.8 mg/g particles) of cryogels was achieved at acetate buffer of pH 5.0 with initial α-amylase concentration of 4 mg/mL. Immobilized enzyme has more stable pH range, between 6 and 7.5 than, the free one. Immobilization also increased the optimal activity from 25 to temperature range of 25-35 °C. Vmax and Km of α-amylase were detected as 1.149 U/mg protein, and 11.6 × 10-1 mM, respectively. α-Amylase was utilized 35 times repeatedly without losing the productivity.


Assuntos
Cromatografia de Afinidade , Cobre/química , Poli-Hidroxietil Metacrilato/química , alfa-Amilases , Adsorção , alfa-Amilases/química , alfa-Amilases/isolamento & purificação
15.
J Chromatogr A ; 1550: 21-27, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29609862

RESUMO

We synthesized Ni2+-attached O-Carboxymethyl chitosan Schiff base complexes embedded composite cryogels (Ni2+-O-CMCS-CCs) by means of polymerization of gel-forming precursors at subzero temperatures. Prepared affinity cryogel showed excellent adsorption performance for lysozyme selected as model protein to test adsorption parameters, demonstrating an adsorption capacity of 244.6 mg/g (15.3 mg/g for Ni2+ minus O-CMCS-CCs), with fast adsorption equilibrium within 30 min and good reversibility. The performance of Ni2+-O-CMCS-CCs for lysozyme was also evaluated by SDS-PAGE, and a purification efficiency of 86.9% with 89.5% purification yield was determined. The swelling test, FT-IR, and SEM analysis were carried out for the characterization of Ni2+-O-CMCS-CCs. At the end of 35 adsorption-desorption cycles, there was no significant change in the adsorption capacity.


Assuntos
Quitosana/análogos & derivados , Cromatografia de Afinidade/métodos , Enzimas Imobilizadas/isolamento & purificação , Metais/química , Muramidase/isolamento & purificação , Bases de Schiff/química , Adsorção , Animais , Galinhas , Quitosana/química , Clara de Ovo/química , Concentração de Íons de Hidrogênio , Íons , Ligantes , Concentração Osmolar , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
16.
Colloids Surf B Biointerfaces ; 163: 266-274, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29316524

RESUMO

Molecularly imprinted polymers which have been extensively investigated as selective adsorbents were constructed using a template molecule during the polymerization to gain template-specific cavities. In this study, we prepared cholesterol imprinted poly(2-hydroxyethyl methacrylate-methacryloyamidotryptophan) (PHEMA-MTrp) particles embedded composite membranes. These membranes were characterized through elemental analysis, FTIR, SEM, swelling tests, and surface area measurements. Adsorption experiments were performed in a batch experimental set-up, and the adsorption medium was either a methanol or intestinal-mimicking solution. Stigmasterol and estradiol were used as competing molecules in selectivity tests. Some results are as follows: the specific surface areas of MIP particle-embedded membranes, NIP particle-embedded membranes, and membranes without particles were 36.5, 29.2 and 13.7 m2/g, respectively. The imprinted membranes were 1.96 and 2.13 times more selective for cholesterol when compared to stigmasterol and estradiol used as competitor agents, respectively. Cholesterol adsorption capacity increased up to 23.43 mg/g with increasing cholesterol concentration of 2 mg/mL. The MIP particle-embedded composite membranes showed a negligible loss in cholesterol adsorption capacity after ten consecutive adsorption cycles using the same adsorbent.


Assuntos
Biomimética , Colesterol/química , Mucosa Intestinal/metabolismo , Membranas Artificiais , Impressão Molecular/métodos , Adsorção , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Ulus Travma Acil Cerrahi Derg ; 23(3): 230-234, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28530777

RESUMO

BACKGROUND: The term mucocele refers to the dilatation of the appendix due to mucus, and it is an uncommon disorder with an estimated incidence of 0.2%-0.3% of all appendectomies performed and 8%-10% of all appendiceal tumors. It is often asymptomatic, but may manifest appendicitis-like symptoms. METHODS: Twenty-six patients (14 females and 12 males) were operated on due to mucocele of the appendix. Sixteen patients exhibiting the characteristics of clinically acute appendicitis required an emergency operation. Appendectomy was performed on 14 patients, and right hemicolectomy was carried out on 2 patients. Of the remaining 10 patients who received surgery under elective conditions, 4 underwent a right hemicolectomy and 6 underwent an appendectomy. RESULTS: The patients' age ranged from 27 to 81 years. Sixteen open and 4 laparoscopic appendectomies were performed. An incidental appendiceal mucocele was identified in 2 patients who had undergone colonoscopy. According to the histopathological examination, the incidence rate of mucosal hyperplasia, mucinous cystadenoma, and mucinous cystadenocarcinoma was found to be 23.1%, 61.4%, and 15.5%, respectively. CONCLUSION: In patients with long-term pain in the right lower quadrant of the abdomen, appendiceal mucocele should be considered, and the results of radiological imaging tests should be carefully analyzed before surgery.


Assuntos
Apêndice/cirurgia , Doenças do Ceco , Mucocele , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças do Ceco/diagnóstico , Doenças do Ceco/cirurgia , Colectomia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucocele/diagnóstico , Mucocele/cirurgia
18.
Mater Sci Eng C Mater Biol Appl ; 73: 15-20, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28183592

RESUMO

In this study, a supermacroporous poly(2-hydroxyethyl methacrylate) (PHEMA)-based Cu2+-attached bentonite particles embedded hybrid monolithic cryogel (Cu2+-ABPs EHMC) was prepared by radical cryo-copolymerization of HEMA with N,N'-methylene-bis-acrylamide (MBAAm) as a cross-linker directly in a plastic syringe in the presence of Cu2+-ABPs, and used for hemoglobin (Hb) separation from aqueous solution. Due to the naturally abundant hydroxyl groups on bentonite, Cu2-attached bentonite particles (Cu2+-ABPs) embedded hybrid monolithic cryogel (HMC) showed a good adsorption performance for Hb, covering an excellent adsorption capacity of 521.6mg/g bentonite in phosphate buffer at pH6.0 with a flow rate of 0.5mL/min, fast binding stability within 60min, well selectivity and reversibility. Compared with other adsorbent systems used for protein separation, this sorbent has many advantages such as excellent adsorption performance, ease of preparation, suitable, effective and environment-friendly to perform, which can serve as a more sustainable material in protein separation and purification.


Assuntos
Criogéis/química , Hemoglobinas/isolamento & purificação , Adsorção , Animais , Bentonita/química , Bovinos , Cobre/química , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Concentração Osmolar , Reologia , Soluções , Temperatura
19.
Artif Cells Nanomed Biotechnol ; 45(1): 90-97, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26755205

RESUMO

In this study, chromatographic performance of Cu2+-attached pumice particles embedded to monolithic cryogels (Cu2+-APPsEMC) for human serum albumin (HSA) was investigated. Monolithic composite cryogels were prepared by means of polymerization of gel-forming precursors at sub-zero temperatures. The chemical composition of pumice and surface of composite cryogels were determined by X-ray fluorescence spectrometer and scanning electron microscopy, respectively. The highest adsorption capacity (549.5 mg/g pumice) of cryogels was achieved at phosphate buffer of pH 8.0 with initial HSA solution of 3 mg/ml. SDS-PAGE analysis was performed for the samples studied on human serum to determine HSA adsorption/desorption performance of cryogel qualitatively.


Assuntos
Cobre/química , Criogéis/química , Albumina Sérica/isolamento & purificação , Silicatos/química , Humanos , Albumina Sérica/química
20.
Mater Sci Eng C Mater Biol Appl ; 70(Pt 1): 552-563, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27770928

RESUMO

Isolation of structurally intact chitin samples for biotechnological applications has gained much recent attention. So far, three-dimensional chitin isolates have been obtained from only diplopods and sponges. In this study, three-dimensional chitin isolates were obtained from the body parts of centipede Scolopendra sp. (antennae, head, forcipule, collum, trunk, trunk legs and last pair of legs) without leading to structural failure. FT-IR spectra of chitin isolates confirmed that chitin samples are in α allomorph. TGA, XRD and SEM analyses and lysozyme adsorption studies revealed that each chitin isolate had different thermal stability, crystallinity and surface characteristics. Among the chitin isolates, Cu(II)-immobilized forcipule chitin showed the highest affinity for lysozyme (54.1mg/g), whereas chitin from last pair of legs exhibited the lowest affinity (3.7mg/g). This study demonstrated that structurally intact chitin isolates can be obtained from the body parts of centipede Scolopendra sp. (antennae, head, forcipule, collum, trunk, trunk legs and last pair of legs) by using a simple chemical procedure. Also, it gives a biotechnological perspective to the organisms in the group of Chilipoda.


Assuntos
Estruturas Animais/química , Artrópodes/anatomia & histologia , Quitina/isolamento & purificação , Muramidase/isolamento & purificação , Adsorção , Animais , Quitina/química , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Termogravimetria , Difração de Raios X
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