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1.
Biomater Adv ; 155: 213696, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37952462

RESUMO

Critical bone defects complicate tissue graft-based surgeries, raising healthcare expenditures and underscoring scaffold-based tissue-engineering strategies to support bone reconstruction. Our study highlighted that the phase-compatible combination of inorganic nanorods, nanofibers, and hydrogels is promising for developing biomimetic and cell-instructive scaffolds since the bone matrix is a porous organic/inorganic composite. In brief, methacrylated gelatin (GelMA) was reacted with dopamine to form catechol-modified GeLMA (GelMA-C). The GelMA-C was nanocoated onto an iron-doped hydroxyapatite (FeHAp) nanorod via metal-catechol network coordination. The modified nanorod (FeHAp@GelMA-C) was loaded onto GelMA-based nanofibers. The nanorods loaded pre-fibers were electrospun onto GelMA solution and photochemically crosslinked to fabricate a fiber-reinforced hydrogel. The structural, mechanical, physicochemical, biocompatibility, swelling properties, osteogenic potential, and bone remodelling potential (using rat femoral defect model) of modified nanorods, simple hydrogel, and nanorod-loaded fiber-reinforced hydrogel were studied. The results supported that the interface interaction between GelMA-C/nanorods, nanorods/nanofibers, nanorods/hydrogels, and nanofiber/hydrogels significantly improved the microstructural and mechanical properties of the scaffold. Compared to pristine hydrogel, the nanorod-loaded fiber-reinforced scaffold better supported cellular responses, osteogenic differentiation, matrix mineralization, and accelerated bone regeneration. The nanorod-loaded fiber-reinforced hydrogel proved more biomimetic and cell-instructive for guided bone reconstruction.


Assuntos
Nanofibras , Nanotubos , Ratos , Animais , Engenharia Tecidual/métodos , Osteogênese , Alicerces Teciduais/química , Hidrogéis , Gelatina/química , Catecóis
2.
Int J Biol Macromol ; 247: 125738, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37423444

RESUMO

Diabetes wounds take longer to heal due to extended inflammation, decreased angiogenesis, bacterial infection, and oxidative stress. These factors underscore the need for biocompatible and multifunctional dressings with appropriate physicochemical and swelling properties to accelerate wound healing. Herein, insulin (Ins)-loaded, and silver (Ag) coated mesoporous polydopamine (mPD) nanoparticles were synthesized (Ag@Ins-mPD). The nanoparticles were dispersed into polycaprolactone/methacrylated hyaluronate aldehyde dispersion, electrospun to form nanofibers, and then photochemically crosslinked to form a fibrous hydrogel. The nanoparticle, fibrous hydrogel, and nanoparticle-reinforced fibrous hydrogel were characterized for their morphological, mechanical, physicochemical, swelling, drug-release, antibacterial, antioxidant, and cytocompatibility properties. The diabetic wound reconstruction potential of nanoparticle-reinforced fibrous hydrogel was studied using BALB/c mice. The results indicated that Ins-mPD acted as a reductant to synthesize Ag nanoparticles on their surface, held antibacterial and antioxidant potential, and their mesoporous properties are crucial for insulin loading and sustained release. The nanoparticle-reinforced scaffolds were uniform in architecture, porous, mechanically stable, showed good swelling, and possessed superior antibacterial, and cell-responsive properties. Furthermore, the designed fibrous hydrogel scaffold demonstrated good angiogenic, anti-inflammatory, increased collagen deposition, and faster wound repair capabilities, therefore, it could be used as a potential candidate for diabetic wound treatment.


Assuntos
Bivalves , Diabetes Mellitus , Nanopartículas Metálicas , Camundongos , Animais , Hidrogéis/química , Prata/química , Insulina , Cicatrização , Nanopartículas Metálicas/química , Antioxidantes , Antibacterianos/farmacologia , Antibacterianos/química , Glicosaminoglicanos
3.
J Mater Chem B ; 11(25): 5830-5845, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37283547

RESUMO

Fabricating an organic-inorganic nanocomposite hydrogel platform with antibacterial, anti-inflammatory, and osteoinductive properties that mimic bone extracellular matrix composition is decisive for guiding bone development in orthopedic practice. Despite significant progress in developing hydrogels for tissue repair, little attention has been paid to replicating the natural bone ECM microenvironments and addressing the importance of anti-inflammatory agents during osteogenesis. Herein, we developed ciprofloxacin and dexamethasone loaded strontium (Sr) and/or iron (Fe) substituted hydroxyapatite (HAp) nanomaterials precipitated in collagen (Col) to construct a multifunctional bioactive nanocomposite hydrogel platform to prevent inflammation and bacterial adhesion, leading to augmenting bone development in the defect site. The fabricated nanocomposite hydrogels (Sr:HAp-Col, Fe:HAp-Col, and Sr/Fe:HAp-Col) were physicochemically characterized and demonstrated high loading and prolonged drug release, and excellent antibacterial activity against Gram-positive and Gram-negative bacteria. In in vitro experiments, the Sr/Fe:HAp-Col sample exhibited enhanced bioactivity against the preosteoblast MC3T3-E1 cell line, with high alkaline phosphatase and bone-like inorganic calcium deposition, as well as increased gene expression of osteogenesis-related differentiation markers, including OPN, OCN, and RUNX2. Furthermore, in vivo experiments revealed that the Sr/Fe:HAp-Col matrix degraded over time by controlling the release of ions into the body, without causing acute inflammation at the implanted site or in the blood serum, or in the internal organs, including the heart, lungs, liver, and kidney of the Sprague-Dawley rat model. The micro-CT scan and histological examination showed high bone mineral density and more mature bone formation at the nanocomposite hydrogel implanted site associated with the ColMA hydrogel in the femur defect of the rat model. The strategy of applying collagen hydrogel supplemented with HAp to bone regeneration is promising due to its ability to mimic the natural bone ECM. Overall, the developed bioactive nanocomposite hydrogel may have great potential not only in bone regeneration but also in repairing nonunion-infected defects of other tissues.


Assuntos
Antibacterianos , Osteogênese , Ratos , Animais , Nanogéis , Antibacterianos/farmacologia , Ratos Sprague-Dawley , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Durapatita/química , Colágeno/química , Anti-Inflamatórios/farmacologia , Inflamação , Hidrogéis/farmacologia
4.
Int J Surg Case Rep ; 105: 108098, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37018950

RESUMO

INTRODUCTION: Pseudomyxoma pleurii is a rare disease that is defined by the pleural extension of pseudomyxoma peritonei, usually secondary to a mucinous neoplasm of the appendix or ovary. It is characterized by diffuse mucinous deposits on the pleural surface. CASE PRESENTATION: A 31-year-old woman presented to the hospital with dyspnea, an increased respiratory rate, and decreased oxygen saturation. Following an appendectomy for a perforated mucinous appendiceal tumor eight years ago, the patient underwent multiple surgeries for the resection of mass deposits in the peritoneal cavity. At presentation, her chest computed tomography with contrast revealed cystic mass deposits on the right-side pleura with a massive multi-locular pleural effusion mimicking hydatid cyst. Upon histopathologic examination, multiple small cystic structures lined by tall columnar epithelium with basally placed bland nuclei floating in the mucin pools were noted. CLINICAL DISCUSSION: Pseudomyxoma peritonei often leads to abdominal distention, intestinal blockage, anorexia, cachexia, and eventually death. It rarely spreads outside the abdomen, and its extension to the pleura is extremely unusual, with only a small number of cases documented in the literature to date. Radiologically, pseudomyxoma pleurii may resemble hydatid cyst of the lung and pleura. CONCLUSION: Pseudomyxoma pleurii is a rare entity with a poor prognosis that usually arises secondary to Pseudomyxoma peritonei. The risk of morbidity and mortality is reduced by early diagnosis and treatment. The present case places emphasis on the inclusion of pseudomyxoma pleurii in the differential diagnosis of pleural lesions in patients with the history of appendiceal or ovarian mucinous tumors.

5.
Int J Surg Case Rep ; 105: 107979, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36933408

RESUMO

INTRODUCTION AND IMPORTANCE: Teratoma is a germ cell tumor originating from pluripotent germ cells and embryonal cells that commonly occurs in the gonads with only 15 % of it arising in extragonadal sites. In infants and children, teratomas of the head and neck are uncommon that comprise 0.47 %-6 % of all teratomas, and their occurrence in parotid gland is extremely rare. It is considered a diagnostic pitfall preoperatively, and their definite diagnosis can only be made upon surgery followed by histopathological examination. CASE PRESENTATION: We present a unique case of parotid gland teratoma in a 9-month-old girl who was brought to the hospital by her parents with right side parotid region swelling since birth. The ultrasonographic findings were suggestive of cystic hygroma. Upon surgery, the mass was completely excised with a part of parotid gland. The diagnosis of mature teratoma was made based on the histopathologic examination. No tumor recurrence was noted during the 4-month postoperative follow-up. CLINICAL DISCUSSION: Teratoma of the parotid gland is an extremely rare entity that may mimic diverse benign and malignant tumors of the salivary gland. Patients often present to the health care facility with a parotid gland swelling leading to defacement. Complete surgical resection of the tumor is considered the best treatment approach with careful preservation of facial nerve. CONCLUSION: Due to the scarcity of information available regarding the behavior and clinical management of parotid gland teratoma in the literature, a good follow-up of patient is required to exclude potential recurrency and neurological deficit.

6.
Urol Case Rep ; 46: 102296, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36506796

RESUMO

Hydatid cyst of Echinococcus granulosus usually develops in liver and lungs of the affected individual and is considered a common health problem in endemic regions. Although, the cyst can be found in less common locations, such as brain, heart, and bones, the urinary bladder is extremely rare that may mimic malignancy radiologically and creates a diagnostic dilemma for clinicians and radiologists. Here we present a unique case of hydatid cyst in the urinary bladder with associated eosinophilic cystitis.

7.
Crit Rev Anal Chem ; : 1-17, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36018260

RESUMO

Heavy metals ions as metallic pollutants are a growing global issue due to their adverse effects on the aquatic ecosystem, and human health. Unfortunately, conventional detection methods such as atomic absorption spectrometry exhibit a relatively low limit of detection and hold numerous disadvantages, and therefore, the development of an efficient method for in-situ and real-time detection of heavy metal residues is of great importance. The aptamer-based sensors offer distinct advantages over antibodies and emerged as a robust sensing platform against various heavy metals due to their high sensitivity, ease of production, simple operations, excellent specificity, better stability, low immunogenicity, and cost-effectiveness. The nucleic acid aptamers in conjugation with nanomaterials can bind to the metal ions with good specificity/selectivity and can be used for on-site monitoring of metal ion residues. This review aimed to provide background information about nanomaterials-based aptasensor, recent advancements in aptamer conjunction on nanomaterials surface, the role of nanomaterials in improving signal transduction, recent progress of nanomaterials-based aptasening procedures (from 2010 to 2022), and future perspectives toward the practical applications of nanomaterials-based aptasensors against hazardous metal ions for food safety and environmental monitoring.

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