RESUMO
This clinical report presents a 7-year-old patient with ectodermal dysplasia and a newly identified ectodysplasin A (EDA) gene mutation (c.965 T>C). A removable partial denture combined with a complete denture was provided after considering the relevant factors. Based on digital smile design, resin crowns were fabricated to restore the cone-shaped teeth esthetically. Facial scan parameters and maxillofacial landmark localization on cone beam computed tomography (CBCT) images were combined for the registration of jaw relation, and a Gothic arch was subsequently 3-dimensionally printed for verification. Ultimately, dentures with accurate occlusion and satisfactory retention were delivered for this young patient with inadequate bone volume and poor fit that markedly improved his esthetics and function.
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Pulp treatment is extremely common in endodontics, with the main purpose of eliminating clinical symptoms and preserving tooth physiological function. However, the effect of dental pulp treatment is closely related to the methods and materials used in the process of treatment. Plenty of studies about calcium silicate-based bioceramics which are widely applied in various endodontic operations have been reported because of their significant biocompatibility and bioactivity. Although most of these materials have superior physical and chemical properties, the differences between them can also have an impact on the success rate of different clinical practices. Therefore, this review is focused on the applications of several common calcium silicate-based bioceramics, including Mineral trioxide aggregate (MTA), Biodentine, Bioaggregate, iRoot BP Plus in usual endodontic treatment, such as dental pulp capping, root perforation repair, regenerative endodontic procedures (REPs), apexification, root-end filling and root canal treatment (RCT). Besides, the efficacy of these bioceramics mentioned above in human trials is also compared, which aims to provide clinical guidance for their clinical application in endodontics.
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Materiais Restauradores do Canal Radicular , Humanos , Materiais Restauradores do Canal Radicular/farmacologia , Materiais Restauradores do Canal Radicular/uso terapêutico , Compostos de Cálcio/farmacologia , Compostos de Cálcio/uso terapêutico , Óxidos/farmacologia , Óxidos/uso terapêutico , Combinação de MedicamentosRESUMO
BACKGROUND: Sodium picosulfate/magnesium citrate (SPMC) is a small-volume bowel cleansing agent with similar efficacy to and better tolerability than polyethylene glycol. However, we found no data on which SPMC preparation (same-day vs. split-dose) provides better bowel cleansing efficacy for afternoon colonoscopy. AIMS: To compare bowel cleansing efficacy of different timing of the regimen. METHODS: This randomized, single-center, endoscopist-blinded, noninferior study compared same-day and split-dose SPMC preparations for afternoon colonoscopy in 101 and 96 patients, respectively. We also included a prospective observation group of 100 patients receiving morning colonoscopy to compare bowel preparation between morning and afternoon colonoscopies. Bowel cleansing efficacy was then evaluated by the Aronchick Scale, Ottawa Bowel Preparation Scale (OBPS), Boston Bowel Preparation Scale (BBPS), and the Bubble Scale. RESULTS: Same-day and split-dose preparations were similar in efficacy in all four scales. In the Aronchick Scale, the success rate (excellent and good cleanliness) was higher in same-day preparation than in split-dose preparation (100% vs. 92.8%). The same-day preparation also obtained a better OBPS score (1.4 vs. 2.1), but BBPS showed no difference between such groups (7.7 vs. 7.4). CONCLUSION: Same-day preparation with SPMC is not inferior to split-dose preparation for afternoon colonoscopy.
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Catárticos , Compostos Organometálicos , Catárticos/efeitos adversos , Citratos/efeitos adversos , Ácido Cítrico , Colonoscopia , Humanos , Compostos Organometálicos/efeitos adversos , Picolinas/efeitos adversos , Polietilenoglicóis , Estudos ProspectivosRESUMO
Masticatory myofascial pain (MMP) is one of the most common causes of chronic orofacial pain in patients with temporomandibular disorders. To explore the antinociceptive effects of ultra-low frequency transcutaneous electrical nerve stimulation (ULF-TENS) on alterations of pain-related biochemicals, electrophysiology and jaw-opening movement in an animal model with MMP, a total of 40 rats were randomly and equally assigned to four groups; i.e., animals with MMP receiving either ULF-TENS or sham treatment, as well as those with sham-MMP receiving either ULF-TENS or sham treatment. MMP was induced by electrically stimulated repetitive tetanic contraction of masticatory muscle for 14 days. ULF-TENS was then performed at myofascial trigger points of masticatory muscles for seven days. Measurable outcomes included maximum jaw-opening distance, prevalence of endplate noise (EPN), and immunohistochemistry for substance P (SP) and µ-opiate receptors (MOR) in parabrachial nucleus and c-Fos in rostral ventromedial medulla. There were significant improvements in maximum jaw-opening distance and EPN prevalence after ULF-TENS in animals with MMP. ULF-TENS also significantly reduced SP overexpression, increased MOR expression in parabrachial nucleus, and increased c-Fos expression in rostral ventromedial medulla. ULF-TENS may represent a novel and applicable therapeutic approach for improvement of orofacial pain induced by MMP.
Assuntos
Dor Crônica/complicações , Dor Crônica/terapia , Transtornos da Articulação Temporomandibular/complicações , Transtornos da Articulação Temporomandibular/fisiopatologia , Estimulação Elétrica Nervosa Transcutânea , Animais , Dor Crônica/fisiopatologia , Modelos Animais de Doenças , Eletromiografia , Fenômenos Eletrofisiológicos , Músculos da Mastigação/fisiopatologia , Placa Motora/fisiopatologia , Síndromes da Dor Miofascial/complicações , Síndromes da Dor Miofascial/fisiopatologia , Síndromes da Dor Miofascial/terapia , Núcleos Parabraquiais/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Receptores Opioides mu/metabolismo , Substância P/metabolismoRESUMO
Extranodal natural killer/T cell lymphoma, nasal type (ENKL) is a highly aggressive tumor with relatively poor prognosis. In this prospective study, we investigated the efficacy and toxicity of a novel GDP-ML regimen (combined gemcitabine, cisplatin, dexamethasone, methotrexate, and pegaspargase) as front-line treatment in newly diagnosed ENKL. Eligible newly diagnosed stage I/II ENKL patients received sandwich chemoradiation therapy. Patients with stage III/IV disease received an initial 4 cycles of GDP-ML regimen. After 4 cycles, responding patients continued to receive either autologous transplantation or additional two courses of GDP-ML. A total of 44 patients were enrolled with a median follow-up of 26 months. The overall response rate (ORR) were 78.6% for the whole cohort, 84.6% for stage I/II, and 66.7% for stage III/IV, and corresponding complete remission (CR) rates were 61.9%, 76.9%, and 33.3%. The 1- year and 2- year progression-free survival (PFS) rates were 69.3% and 62.9%, and 1- year and 2-year overall survival (OS) rates were 76.5% and 67.4%, respectively. Patients with stage I/II disease showed better 2-year OS rate compared with stage III/IV patients (88.1% vs. 33.2%, p < 0.001). Patients who achieved CR had significantly better 2-year OS rate compared with non-CR patients (90.8% vs. 24.5%, p < 0.001). The main adverse event was hematologic toxicity. Grade 3/4 neutropenia occurred in 59.1% of patients. These results indicate that GDP-ML is an effective and well-tolerated induction regimen with newly diagnosed ENKL patients. This clinical trial was registered on www.chictr.org.cn (ChiCTR-ONC-12002055).
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Asparaginase/administração & dosagem , Cisplatino/administração & dosagem , Desoxicitidina/análogos & derivados , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Metotrexato/administração & dosagem , Neoplasias Nasais/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Adulto , Idoso , Desoxicitidina/administração & dosagem , Feminino , Seguimentos , Humanos , Linfoma Extranodal de Células T-NK/diagnóstico por imagem , Linfoma Extranodal de Células T-NK/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias Nasais/diagnóstico por imagem , Neoplasias Nasais/mortalidade , Estudos Prospectivos , Taxa de Sobrevida/tendências , Adulto Jovem , GencitabinaRESUMO
This study explores the involvement of substance P (SP) in the parabrachial nucleus (PBN) and central amygdaloid nucleus (CeA) in the nociception-emotion link and of rats with masticatory myofascial pain (MMP) induced by chronic tetanic eccentric muscle contraction. A total of 18 rats were randomly and equally assigned for MMP (MMP group) and sham-MMP induction (sMMP group). MMP was induced by electrical-stimulated repetitive tetanic eccentric contraction of the masseter muscle for 14 consecutive days. Myofascial trigger points in the masseter muscle were identified by palpable taut bands, increased prevalence of endplate noise (EPN), focal hypoechoic nodules on ultrasound and restricted jaw opening. All animals were killed for morphological and SP immunohistochemical analyses. Chronic tetanic eccentric contraction induced significantly thicker masseter muscle confirmed by hypoechogenicity, increased prevalence and amplitudes of EPN, and limited jaw opening. Immunohistochemically, the SP-like positive neurons increased significantly in PBN and CeA of the MMP group. Our results suggested that MMP increases the SP protein levels in PBN and CeA, which play important roles in MMP-mediated chronic pain processing as well as MMP-related emotional processes.
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Dor Crônica , Síndromes da Dor Miofascial , Tonsila do Cerebelo , Animais , Dor Crônica/diagnóstico por imagem , Nociceptividade , Ratos , Substância PRESUMO
Purpose: To report a rare complication that Onyx gel blocked the MCA trunk and branches unexpectedly during AVM embolism and our strategy to rescue. Material and methods: A 16 years old otherwise healthy girl hold a left side Spetzler - Martin grade III fronto-temporal AVM, during embolization, the L-MCA and its branches were blocked by Onyx completely, the patient was transferred to the operating room to extract the Onyx gel immediately. Result: After totally 10 arterotomies, all the Onyx gel were removed. 8 hours after occlusion, all arteries were then seen to pulsate. Conclusion: Iatrogenic MCA full-length acute occlusion is a rare and severe complication during AVM embolism. Carefully identify the feeding arteries, micro-catheter angiography before Onyx gel injection and balloon-assisted embolism could probably prevent it. Surgical operation to extract onyx gel and re-canalize MCA was recommended, AVM should be resect if possible.
Assuntos
Embolia , Embolização Terapêutica , Adolescente , Dimetil Sulfóxido , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/cirurgia , Polivinil , Resultado do TratamentoRESUMO
Aim: Methotrexate (Mtx) is prescribed to reduce pain and inflammation in arthritis patients; however, improved repair and mobility of joints still are the major concerns. Magnesium oil (MO) improves joint mobility and repair; therefore, MO-assisted transdermal delivery of Mtx was aimed.Methods: MO integrated Mtx nanoemulsion (Mtx-MONE) was prepared with uniform size (175 ± 35.4 nm), pH (6.15 ± 0.3) near to skin pH, and high entrapment efficiency (65 ± 8.6%). Mtx-MONE was transformed to nanogel (Mtx-MONEG) with semisolid consistency (43,408 ± 77.72 cP) and good spreadability (3.63 ± 0.033 mJ).Results: Mtx-MONEG showed significant reduction in oedema, arthritic scores, level of inflammatory cytokines, and improved walking as compared to diseased control. MO offered additional improvements in joints, mobility, and repair.Conclusion: Transdermal delivery of Mtx has been successfully achieved by Mtx-MONEG. Tremendous recovery from inflammation, improved joints mobility and repair, and reduced pain strongly support the use of MO as an adjutant of Mtx for improved transdermal application.
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Anti-Inflamatórios/uso terapêutico , Artrite Experimental/tratamento farmacológico , Magnésio/uso terapêutico , Metotrexato/uso terapêutico , Nanogéis/uso terapêutico , Administração Cutânea , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacocinética , Artrite Experimental/imunologia , Artrite Experimental/patologia , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Magnésio/administração & dosagem , Magnésio/farmacocinética , Metotrexato/administração & dosagem , Metotrexato/farmacocinética , Nanogéis/administração & dosagem , Ratos Sprague-DawleyRESUMO
According to the fact that gecko-inspired vertically aligned carbon nanotubes (VA-CNTs) exhibit ultrastrong adhesion, dopamine is utilized to make a modification to this traditional biomimetic material. The composite material is tested for adhesion performance under different environmental conditions by an atomic force microscope. The adhesion force of the modified VA-CNTs does not show obvious fluctuation during the gradual heating process; however, the material gains improved adhesion when increasing the ambient humidity. In addition, the modified CNTs show a stronger adhesion force than the original CNTs in their performance tests. The dopamine polymer has a good combination with CNTs, which is responsible for the aforementioned excellent performance. Overall, this modification method is simple, convenient, efficient, and environmentally friendly, which all indicates a promising future in its application. The modified CNTs are expected to be used for super-adhesion in harsh environments, as well as in the field of microelectronics.
Assuntos
Dopamina/química , Nanotubos de Carbono/química , Umidade , Polímeros/químicaRESUMO
Freshness protection packages and preservative films are widely used food-contact plastic made of polyethylene. Diode array detector (DAD), charged aerosol detector (CAD) and evaporative light-scattering detector (ELSD) were evaluated for determination of 6 bisphenols (bisphenol A, bisphenol S, bisphenol F, bisphenol B, bisphenol AF and tetrabromobisphenol A.) in polyethylene. DAD presented better parameters including limit of quantification (LOQs) ranging from 0.05 to 0.5⯵g/g with relative standard deviations (RSDs, nâ¯=â¯5) lower than 1% at two concentration levels. CAD and ELSD are universal detectors with relative consistent response parameters for different analogues which have potential application by using single calibrant for quantification of multiple analytes. Matrix effects were barely observed on three detectors. Samples of freshness protection packages and preservative films were further analyzed and preliminary profiles of bisphenols in products from Beijing market was obtained. Bisphenol S have become most abundant analogue instead of bisphenol A in investigated products.
Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Embalagem de Alimentos , Fenóis/análise , Polietileno/química , Sulfonas/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Limite de DetecçãoRESUMO
Since the maximum foaming temperature window is only about 4 °C for supercritical CO2 (scCO2) foaming of pristine polypropylene, it is important to raise the melt strength of polypropylene in order to more easily achieve scCO2 foaming. In this work, radiation cross-linked isotactic polypropylene, assisted by the addition of a polyfunctional monomer (triallylisocyanurate, TAIC), was employed in the scCO2 foaming process in order to understand the benefits of radiation cross-linking. Due to significantly enhanced melt strength and the decreased degree of crystallinity caused by cross-linking, the scCO2 foaming behavior of polypropylene was dramatically changed. The cell size distribution, cell diameter, cell density, volume expansion ratio, and foaming rate of radiation-cross-linked polypropylene under different foaming conditions were analyzed and compared. It was found that radiation cross-linking favors the foamability and formation of well-defined cell structures. The optimal absorbed dose with the addition of 2 wt % TAIC was 30 kGy. Additionally, the foaming temperature window was expanded to about 8 °C, making the handling of scCO2 foaming of isotactic polypropylene much easier.
Assuntos
Compostos Alílicos/química , Dióxido de Carbono/química , Reagentes de Ligações Cruzadas/efeitos da radiação , Polímeros/química , Polipropilenos/química , Dióxido de Carbono/efeitos da radiação , Radioisótopos de Cobalto , Raios gama , Polipropilenos/efeitos da radiação , TemperaturaRESUMO
PURPOSE: The purpose of this study was to investigate the outcomes of using cementless femoral stem for extensive osteonecrosis of the femoral head involving the proximal femur. METHODS: A total of 21 patients (27 hips) in the study group defined as extensive ONFH involving proximal femur and 42 patients (52 hips) with the diagnosis of regular osteonecrosis of the femoral head in the control group were enrolled in the study. Clinical and radiographic follow-ups were documented at three, six, 12 and 24 months postoperatively. RESULTS: Results improved for Harris hip score in both groups. In the study group undersized stem implantation and lateralized mal-position were identified. Subsequent subsidence was also found. CONCLUSIONS: Pre-operative templating and intra-operative X-ray confirmation are necessary to avoid complications.
Assuntos
Artroplastia de Quadril/métodos , Necrose da Cabeça do Fêmur/cirurgia , Prótese de Quadril , Adulto , Idoso , Cimentação , Feminino , Necrose da Cabeça do Fêmur/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/complicações , Desenho de Prótese , Resultado do TratamentoRESUMO
Taking α-asarone as model drug, mono methoxy polyethylene glycol-polylactic acid copolymer (mPEG-PLA) as the drug carrier material to prepare drug-loading nanoparticles by premix membrane emulsification for nasal administration. The prepared nanoparticles were spherical with smooth surface and average particle size of 360 nm. Polydispersity index (PDI) was 0. 030, average drug loading of (11.5 ± 0.045) % (n = 3), and the encapsulation efficiency of (86.34 ± 0.11) % (n = 3). X-ray diffraction and differential scanning calorimetry results showed that, α-asarone existed in mPEG-PLA carrier in amorphous or molecular state, different from simple physical mixture. In the in vitro release test in simulated human nasal cavity, α-asarone apis can be released quickly at close to 94% at 102 h, in line with the first-order kinetics (R² = 0.981 9). mPEG-PLA drug-loading nanoparticles release only 54%, with slow release effect, in line with Riger-Peppas model (R² = 0.967 9, n = 0.630 2), for non-fick diffusion, released by the spread of drugs and skeleton dissolution dual control. This provided the foundation for nasal drug delivery in vivo pharmacokinetic study.
Assuntos
Anisóis/química , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Administração Intranasal , Derivados de Alilbenzenos , Varredura Diferencial de Calorimetria , Solubilidade , Difração de Raios XRESUMO
Ionic liquid-modified magnetic polymeric microspheres (ILMPM) were prepared based on Fe3O4 magnetic nanoparticles (MNPs) and ionic liquids (ILs) incorporated into a polymer. The composites were characterized using scanning electron microscopy, Fourier transform infrared analysis, thermogravimetric analysis, X-ray diffraction, and vibrating magnetometer, which indicated that ILMPM had a regularly spherical shape and strong magnetic property. The obtained ILMPM were successfully applied as a special adsorbent of magnetic dispersive solid phase extraction (MDSPE) for the rapid extraction and isolation of sulfamonomethoxine sodium and sulfachloropyrazine sodium in urine. The factors that affected extraction efficiency, such as adsorption conditions, desorption conditions, washing and elution solvents, and pH of the sample solution, were optimized. Under the optimum condition, good linearity in the range of 0.005-2.0 µg g(-1) (r ≥ 0.9996) was obtained for the two sulfonamides (SAs); the average recoveries at three spiked levels ranged from 86.9 to 102.1 %, with relative standard deviations of ≤4.3 %. The presented ILMPM-MDSPE method combined the advantages of ILs, MNPs, and MDSPE and therefore could be potentially applied for rapid screening of SAs in urine.
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Polímeros/química , Extração em Fase Sólida/instrumentação , Sulfamonometoxina/isolamento & purificação , Sulfanilamidas/isolamento & purificação , Adsorção , Humanos , Líquidos Iônicos/química , Fenômenos Magnéticos , Microesferas , Extração em Fase Sólida/métodos , Sulfamonometoxina/urina , Sulfanilamidas/urinaRESUMO
Polyphenolic compound-modified hydrogel wound dressings with excellent wet tissue adhesion, antimicrobial properties, stretchability, and full-thickness skin healing properties are still extremely rare so far. Polyphenolic compounds such as tannic acid or dopamine can improve the antibacterial and bioadhesive properties of hydrogels, and are also polymerization inhibitors for free radical polymerization. In this study, polyacrylic acid (PAA) aqueous solution was first synthesized, and then antibacterial PAA-TA hydrogel was prepared by mixing it with tannic acid (TA) and the crosslinker 1,6-hexanediol bis(2-methyl-1-propionic acid azide) (HBMAP). This method avoids the hindrance of the phenolic hydroxyl groups in TA on acrylic acid polymerization, and we were able to obtain a series of TA hydrogels (in the range of 0-15 wt.%. We applied these PAA-TA hydrogels to wound dressings and found that they had excellent adhesion to biological tissues, and the tensile strength and elongation at break of PAA-TA hydrogels with 15 wt.%TA content were as high as 1.72 MPa and 1446.3% in tensile strength evaluation. In addition, microbiological analysis showed that wound dressings had significant antimicrobial activity against Staphylococcus aureus and Escherichia coli. In vitro wound healing experiments confirmed that the wound dressing was biocompatible and could significantly promote the healing of full-thickness skin defects in the guinea pig model. Our work describes an injectable, self-healing, antimicrobial hydrogel that may have promising clinical applications as a wound dressing material.
Assuntos
Resinas Acrílicas , Anti-Infecciosos , Hidrogéis , Polifenóis , Animais , Cobaias , Antibacterianos/farmacologia , Bandagens , Escherichia coliRESUMO
This study aimed to evaluate the properties of radiation cross-linked collagen scaffold (RCS) and its efficacy for alveolar ridge preservation (ARP). RCS was prepared from collagen dispersion by electron beam irradiation and freeze-drying. The microstructure, swelling ratio, area alteration and mechanical properties of RCS were characterized. Fifty-four New Zealand rabbits performing incisor extraction on maxilla and mandible were randomly assigned into positive, sham operation or treatment groups. Micro-computed tomography (micro-CT) scans, performed after 1, 4, and 12 weeks of surgery, were to assess changes in ridge height at buccal and palatal side, in ridge width and in micromorphological parameters. Histological analysis accessed socket microarchitecture. The results showed that RCS had stable mechanical properties and morphologic features that provided a reliable physical support for ARP. Dimensional changes in treatment group revealed significantly greater vertical height at buccal (5.32 [3.37, 7.26] mm, p < .0001) and palatal (4.37 [2.66, 6.09] mm, p < .0001) side, and horizontal width at the maxilla (0.16 [0.04, 0.28] mm, p < .01) and mandible (0.33 [0.11, 0.54] mm, p < .01) than those in sham operation group after 12 weeks. The treatment group had advantage than positive group in vertical height preservation, quantitatively. The order and density of bone trabeculae were improved in treatment group. These findings indicated that RCS had the potential to serve as an effective scaffold for ARP.
Assuntos
Colágeno , Alicerces Teciduais , Extração Dentária , Alvéolo Dental , Animais , Coelhos , Colágeno/química , Alicerces Teciduais/química , Processo Alveolar/diagnóstico por imagem , Microtomografia por Raio-X , MasculinoRESUMO
Nanocellulose, as a nanoscale polymer material, has garnered significant attention worldwide due to its numerous advantages including excellent biocompatibility, thermal stability, non-toxicity, large specific surface area, and good hydrophilicity. Various methods can be employed for the preparation of nanocellulose. Traditional approaches such as mechanical, chemical, and biological methods possess their own distinct characteristics and limitations. However, with the growing deterioration of our living environment, several green and environmentally friendly preparation techniques have emerged. These novel approaches adopt eco-friendly technologies or employ green reagents to achieve environmental sustainability. Simultaneously, there is a current research focus on optimizing traditional nanocellulose preparation methods while addressing their inherent drawbacks. The combination of mechanical and chemical methods compensates for the limitations associated with using either method alone. Nanocellulose is widely used in wound dressings owing to its exceptional properties, which can accelerate the wound healing process and reduce patient discomfort. In this paper, the principle, advantages and disadvantages of each preparation method of nanocellulose and the research findings in recent years are introduced Moreover, this review provides an overview of the utilization of nanocellulose in wound dressing applications. Finally, the prospective trends in its development alongside corresponding preparation techniques are discussed.
Assuntos
Celulose , Polímeros , Humanos , Celulose/química , Estudos Prospectivos , Bandagens , CicatrizaçãoRESUMO
Fate and transport of nanoplastics in aquatic environments are affected by their heteroaggregation with minerals in the presence of macromolecules. This study investigated the heteroaggregation of polystyrene nanoplastics (PSNPs) with goethite nanoparticles (GNPs) under the influence of macromolecules [humic acid (HA), bovine serum albumin (BSA), and DNA] and electrolytes. Under 1 mg C/L macromolecule, raising electrolyte concentration promoted heteroaggregation via charge screening, except that calcium bridging with HA also enhanced heteroaggregation at CaCl2 concentration above 5 mM. At all NaCl concentrations and CaCl2 concentration below 5 mM, 1 mg C/L macromolecules strongly retarded heteroaggregation, ranking BSA > DNA > HA. Raising macromolecule concentration strengthened such stabilization effect of all macromolecules in NaCl solution and that of DNA and BSA in CaCl2 solution by enhancing steric hindrance. However, 0.1 mg C/L BSA slightly promoted heteroaggregation in CaCl2 solution due to stronger electrostatic attraction than steric hindrance. In CaCl2 solution, raising HA concentration strengthened its destabilization effect via calcium bridging. Macromolecules having more compact globular structure and higher molecular weight may exert greater steric hindrance to inhibit heteroaggregation more effectively. This study provides new insights on the effects of macromolecules and electrolytes on heteroaggregation between nanoplastics and iron minerals in aquatic environments.
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Eletrólitos , Compostos de Ferro , Minerais , Nanopartículas , Poliestirenos , Poluentes Químicos da Água , Poliestirenos/química , Minerais/química , Eletrólitos/química , Compostos de Ferro/química , Nanopartículas/química , Poluentes Químicos da Água/química , Cinética , DNA/química , DNA/efeitos dos fármacos , Soroalbumina Bovina/química , Cloreto de Cálcio/químicaRESUMO
Microplastic pollution is not only an environmental problem but also a social problem. Many studies have been conducted on the sources, abundance, and distribution of microplastics in the environment, but an understanding of human exposure levels and potential health risks remains very limited. Based on the bibliometric methods, the present review systematically summarized the exposure pathways of microplastics in humans, and then the characteristics and potential adverse impacts on human health were expounded upon. Available literature showed that microplastics in human bodies were mainly concentrated on sizes smaller than 50 µm, and polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) were the main polymers. Microplastics in environments entered human bodies mainly through food and respiratory pathways, then accumulated in lung and gastrointestinal tissues. Most importantly, small-sized microplastics could distribute in tissues and organs via the circulatory system. The results from lab-based toxicological experiments showed that microplastics not only posed threats to cell membrane integrity, immune stress, gut microbiota, and energy metabolism but also had potentially adverse impacts on the reproductive system. To further understand the health risks of microplastic pollution, it is necessary to promote research on the toxicological effects of microplastics as well as the inner mechanisms and also to establish risk assessment frameworks for evaluating microplastic pollution. These works are crucial to preventing the risks of microplastic pollution with scientific evidence.
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Microplásticos , Poluentes Químicos da Água , Humanos , Microplásticos/toxicidade , Plásticos/efeitos adversos , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluição AmbientalRESUMO
Epidural fibrosis (EF), associated with various biological factors, is still a major troublesome clinical problem after laminectomy. In the present study, we initially demonstrate that sensory nerves can attenuate fibrogenic progression in EF animal models via the secretion of calcitonin gene-related peptide (CGRP), suggesting a new potential therapeutic target. Further studies showed that CGRP could inhibit the reprograming activation of fibroblasts through PI3K/AKT signal pathway. We subsequently identified metformin (MET), the most widely prescribed medication for obesity-associated type 2 diabetes, as a potent stimulator of sensory neurons to release more CGRP via activating CREB signal way. We copolymerized MET with innovative polycaprolactone (PCL) nanofibers to develop a metformin-grafted PCL nanoscaffold (METG-PCLN), which could ensure stable long-term drug release and serve as favorable physical barriers. In vivo results demonstrated that local implantation of METG-PCLN could penetrate into dorsal root ganglion cells (DRGs) to promote the CGRP synthesis, thus continuously inhibit the fibroblast activation and EF progress for 8 weeks after laminectomy, significantly better than conventional drug loading method. In conclusion, this study reveals the unprecedented potential of sensory neurons to counteract EF through CGRP signaling and introduces a novel strategy employing METG-PCLN to obstruct EF by fine-tuning sensory nerve-regulated fibrogenesis.