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1.
BMC Biotechnol ; 24(1): 25, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689309

RESUMO

The reconstruction of a stable, nipple-shaped cartilage graft that precisely matches the natural nipple in shape and size on the contralateral side is a clinical challenge. While 3D printing technology can efficiently and accurately manufacture customized complex structures, it faces limitations due to inadequate blood supply, which hampers the stability of nipple-shaped cartilage grafts produced using this technology. To address this issue, we employed a biodegradable biomaterial, Poly(lactic-co-glycolic acid) (PLGA), loaded with Cell-Free Fat Extract (Ceffe). Ceffe has demonstrated the ability to promote angiogenesis and cell proliferation, making it an ideal bio-ink for bioprinting precise nipple-shaped cartilage grafts. We utilized the Ceffe/PLGA scaffold to create a porous structure with a precise nipple shape. This scaffold exhibited favorable porosity and pore size, ensuring stable shape maintenance and satisfactory biomechanical properties. Importantly, it could release Ceffe in a sustained manner. Our in vitro results confirmed the scaffold's good biocompatibility and its ability to promote angiogenesis, as evidenced by supporting chondrocyte proliferation and endothelial cell migration and tube formation. Furthermore, after 8 weeks of in vivo culture, the Ceffe/PLGA scaffold seeded with chondrocytes regenerated into a cartilage support structure with a precise nipple shape. Compared to the pure PLGA group, the Ceffe/PLGA scaffold showed remarkable vascular formation, highlighting the beneficial effects of Ceffe. These findings suggest that our designed Ceffe/PLGA scaffold with a nipple shape represents a promising strategy for precise nipple-shaped cartilage regeneration, laying a foundation for subsequent nipple reconstruction.


Assuntos
Cartilagem , Condrócitos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Engenharia Tecidual/métodos , Condrócitos/citologia , Cartilagem/citologia , Cartilagem/crescimento & desenvolvimento , Proliferação de Células/efeitos dos fármacos , Materiais Biocompatíveis/química , Coelhos , Porosidade , Ácido Poliglicólico/química , Neovascularização Fisiológica/efeitos dos fármacos
2.
J Biol Chem ; 298(12): 102659, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36328246

RESUMO

Self-association of WT ß2-microglobulin (WT-ß2m) into amyloid fibrils is associated with the disorder dialysis related amyloidosis. In the familial variant D76N-ß2m, the single amino acid substitution enhances the aggregation propensity of the protein dramatically and gives rise to a disorder that is independent of renal dysfunction. Numerous biophysical and structural studies on WT- and D76N-ß2m have been performed in order to better understand the structure and dynamics of the native proteins and their different potentials to aggregate into amyloid. However, the structural properties of transient D76N-ß2m oligomers and their role(s) in assembly remained uncharted. Here, we have utilized NMR methods, combined with photo-induced crosslinking, to detect, trap, and structurally characterize transient dimers of D76N-ß2m. We show that the crosslinked D76N-ß2m dimers have different structures from those previously characterized for the on-pathway dimers of ΔN6-ß2m and are unable to assemble into amyloid. Instead, the crosslinked D76N-ß2m dimers are potent inhibitors of amyloid formation, preventing primary nucleation and elongation/secondary nucleation when added in substoichiometric amounts with D76N-ß2m monomers. The results highlight the specificity of early protein-protein interactions in amyloid formation and show how mapping these interfaces can inform new strategies to inhibit amyloid assembly.


Assuntos
Amiloidose , Microglobulina beta-2 , Humanos , Microglobulina beta-2/química , Amiloide/química , Proteínas Amiloidogênicas/genética , Substituição de Aminoácidos , Amiloidose/genética , Fenômenos Biofísicos , Polímeros
3.
Bioprocess Biosyst Eng ; 45(6): 1011-1018, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35312864

RESUMO

This study proposed a recyclable p-toluenesulfonic acid (p-TsOH) fractionation process for co-producing lignin nanoparticles (LNPs) and fermentable sugars from lignocellulosic biorefinery biowaste (enzymatic hydrolysis residue (EHR)). The prepared LNPs were used to detoxify the inhibitors in the xylose-rich prehydrolyzate for improving ethanol production. Results showed that the EHR was fractionated into a cellulose-rich water-insoluble solid (WIS) fraction and a lignin-rich spent liquor (SL) fraction. Cellulase hydrolysis of WIS produced 97.7% of glucose yield, while the LNPs of an average particle size of 98.0 nm with 76.3 % yield (based on the untreated EHR) were obtained from the diluted SL. LNPs demonstrated higher detoxification ability than EHR at the same dosage. Moreover, the fermentability of the detoxified xylose-rich prehydrolyzate was significantly improved. The sugar utilization ratio was 94.8%, and the ethanol yield reached its peak value of 85.4% after 36 h of fermenting the detoxified xylose-rich prehydrolyzate.


Assuntos
Lignina , Nanopartículas , Etanol , Fermentação , Hidrólise , Lignina/química , Xilose
4.
BMC Urol ; 21(1): 6, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407368

RESUMO

BACKGROUND: Although several distribution patterns of periprostatic neurovascular bundles have been proposed, variant dissection technique based on these patterns still confused surgeons. The aim of this study was to describe the periprostatic neurovascular bundles and their relationship with the fascicles around prostate and provide the accurate morphologic knowledge of periprostatic tissue for prostate operation. METHODS: The pelvic viscera were obtained from 26 adult male cadavers. They were embedded in celloidin and cut into successive slices. The slices were explored with anatomic microscopy. 3-Dimensional reconstruction was achieved with celloidin sections and series software. RESULTS: The prostatic capsule which surrounded the dorsal, bilateral aspect of the prostate was attached ventrally to anterior fibrous muscular stroma (AFMS). The lower part of the striated sphincter completely embraced the urethral; the upper part of this muscle covered the lower ventral surface of prostate. The upper ventral surface of prostate is covered by the circular muscle of detrusor. The levator fascia and the capsule adhered on the most convex region of the lateral prostate, but separated on the other region. The pelvic neurovascular bundles (PNVB) divided into the anterior and posterior divisions. The anterior division continued as dorsal vascular complex (DVC). The distal part of DVC entered into penile hilum. The posterior division continued as neurovascular bundles, and then as the cavernous supply (CS). The distal part of CS joined into pudendal neurovascular bundles. CONCLUSIONS: The capsule and AFMS formed a pocket like complex. There were anterior and posterior neurovascular approaches from PNVB to penile hilum.


Assuntos
Próstata/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Vasos Sanguíneos/anatomia & histologia , Cadáver , Colódio , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso/anatomia & histologia
5.
Molecules ; 25(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266038

RESUMO

The stability of the suspension system of the two crystal forms of pyraclostrobin is evaluated using multiple light technology, and the adsorption performance of polycarboxylate dispersant on the surface of two different crystalline pyraclostrobin particles is compared in combination with XRD, FTIR, XPS, and SEM from the microscopic view. The adsorption kinetics and thermodynamics studies of 2700 on the surfaces of different crystalline forms of pyraclostrobin particles show that the adsorption process of 2700 on the surfaces of pyraclostrobin crystal forms II and IV conform to pseudo-second-order kinetic adsorption model. The Ea values for crystal forms II and IV are 12.93 and 14.39 kJ∙mol-1, respectively, which indicates that both adsorption processes are physical adsorption. The adsorption models of 2700 on the surfaces of pyraclostrobin crystal forms II and IV are in accordance with Langmuir adsorption isotherms. The ∆Gad values of crystal forms II and IV are negative and the ∆Sad values are positive at different temperatures. Therefore, the adsorption processes are spontaneous and accompanied by entropy increase. The results of this study provide an important theoretical basis for the selection of polycarboxylate dispersants in the suspension of pyraclostrobin. This study also provides a reference for the research of polycrystalline pesticide suspension concentrate.


Assuntos
Fungicidas Industriais/química , Cimento de Policarboxilato/química , Estrobilurinas/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica
6.
Arch Microbiol ; 201(5): 581-589, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30478728

RESUMO

During the bioconversion of xylose to ethanol, Pichia stipitis cells are often inhibited by substances generated in the lignocellulosic hydrolysate. However, the response mechanism of P. stipitis to inhibitors has not been completely understood till date. With this aim, integrated transcriptomic and metabolomic analyses were performed on P. stipitis to investigate the interactive effects of three representative inhibitors [vanillin, 5-hydroxymethylfurfural (5-HMF), and acetic acid] present in lignocellulosic hydrolysates. The genes involved in carbohydrate metabolism were observed to significantly down-regulated in the presence of the three combined inhibitors in both lag and middle exponential phases. In addition, inhibitor addition induced amino acid metabolism (e.g., glutamine and asparagine syntheses), since the yeast cells required more amino acids in stressful conditions. The metabolomic analysis yielded similar results, particularly those related with the analysis of metabolic biomarkers including fatty acids, amino acids, and sugars. 70 intracellular metabolites were detected by gas chromatography coupled with mass spectrometry (GC-MS), and samples from different phases were clearly separated by principal component analysis (PCA). The large amount of specific responsive genes and metabolites highlighted the complex regulatory mechanisms involved in the fermentation process in the presence of the three combined inhibitors.


Assuntos
Ácido Acético/farmacologia , Benzaldeídos/farmacologia , Fermentação/efeitos dos fármacos , Furaldeído/análogos & derivados , Pichia/genética , Pichia/metabolismo , Aminoácidos/metabolismo , Etanol/metabolismo , Furaldeído/farmacologia , Lignina/metabolismo , Metaboloma/fisiologia , Análise de Componente Principal , Transcriptoma/genética , Xilose/metabolismo
7.
J Nanobiotechnology ; 17(1): 110, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623629

RESUMO

BACKGROUND: Triple negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes and is one of the most fatal diseases for women. Combining cytotoxic chemotherapy with immunotherapy has shown great promise for TNBC treatment. However, chemotherapy often leads to the development of chemoresistance and severe systemic toxicity compromising the immune functions that are crucial to anti-TNBC immune therapy. Tumor-induced immunosuppression also poses a great hindrance to efficacious anti-TNBC immunotherapy. Nanomedicine holds great promise to overcome these hurdles. RESULTS: Doxorubicin-polyglycerol-nanodiamond conjugate (Nano-DOX) was firstly found to be a cytostatic agent to the 4T1 cells and displayed a lower apparent therapeutic potency than DOX. However, the tumor-bearing animals, particularly some key immune cells thereof, showed good tolerance of Nano-DOX as opposed to the severe toxicity of DOX. Next, Nano-DOX did not induce significant upregulation of P-gp and IL-6, which were demonstrated to be key mediators of chemoresistance to DOX in the 4T1 cells. Then, Nano-DOX was shown to downregulate tumor-derived granulocyte-colony stimulating factor (G-CSF) and suppresses the induction and tissue filtration of myeloid-derived suppressor cells (MDSCs) that are the principal effectors of cancer-associated systemic immunosuppression. Nano-DOX also alleviated the phenotype of MDSCs induced by 4T1 cells. Finally, Nano-DOX induced the 4T1 cells to emit damage associated molecular patterns (DAMPs) that stimulated the tumor immune microenvironment through activating key immune effector cells involved in anti-tumor immunity, such as macrophages, dendritic cells and lymphocytes in the tumor tissue. CONCLUSIONS: Nano-DOX is a cytostatic agent with good host tolerance which is capable of evading chemoresistance and reversing cancer-induced immunosuppression both at the systemic level and in the tumor microenvironment in TNBC. Our work presents Nano-DOX as an interesting example that a chemotherapeutic agent in nano-form may possess distinct biochemical properties from its free form, which can be exploited to join chemotherapy with immunotherapy for better treatment of cancer.


Assuntos
Antineoplásicos/administração & dosagem , Citostáticos/administração & dosagem , Doxorrubicina/administração & dosagem , Glicerol/química , Nanoconjugados/química , Polímeros/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Citostáticos/uso terapêutico , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Nanodiamantes/química , Neoplasias de Mama Triplo Negativas/imunologia , Microambiente Tumoral/efeitos dos fármacos
8.
J Prosthet Dent ; 120(2): 319.e1-319.e6, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30097265

RESUMO

STATEMENT OF PROBLEM: Components fabricated by selective laser melting (SLM) deform because of residual stress, but heat treatment allows the release of that stress and avoids deformation. Although dental cobalt-chromium (Co-Cr) alloy has been specifically designed for SLM, the effects of heat treatment on the metal-ceramic combination of SLM Co-Cr restorations require investigation. PURPOSE: The purpose of this in vitro study was to evaluate the effects of heat treatment on the metal-ceramic combination of SLM Co-Cr alloy. MATERIAL AND METHODS: Following ISO 9693:2012, Co-Cr metal strips (Solibond C Plus cast alloy and SLM powders; YETI Dental) were fabricated with a dimension of 25×3×0.5 mm by casting and SLM. The SLM specimens were divided into 3 subgroups (n=15 for each subgroup). Two subgroups were subjected to heat treatment at 880°C (SLM-880) and 1100°C (SLM-1100). The third subgroup was not subjected to heat treatment and served as a control (As-SLM). Cast specimens (n=15) also acted as a control. A porcelain layer with a thickness of 1.1 mm was fired to the central area (3×8 mm) of each specimen. The 3-point bend test was used to evaluate the metal-ceramic bond strength (τb). The fractured metal surfaces were examined by the naked eye, using a digital camera, and also using a scanning electron microscope. The area fraction of adherence porcelain (AFAP) was determined by measuring the atomic percentage of silicon using energy-dispersive x-ray spectroscopy (EDS). One-way ANOVA and the Kruskal-Wallis test, followed by the Mann-Whitney test (α=.05), were used for statistical analysis. RESULTS: The 1-way ANOVA found no significant difference in the bond strength among the 4 groups. The EDS analysis indicated that specimens in the groups receiving heat treatment (SLM-880 and SLM-1100) showed higher AFAP values than those in the As-SLM group (P<.05). The SLM-880 also showed significantly higher AFAP values than the SLM-1100. Compared with the cast group, significant differences in AFAP values were also observed, and the specimens in the order of highest to lowest AFAP values were SLM-880>cast>As-SLM; no significant difference was found between the SLM-1100 and cast groups. CONCLUSIONS: Heat treatment at 880°C and 1100°C did not affect the metal-ceramic bond strength of Co-Cr alloy made by SLM but did improve the porcelain adherence. SLM-fabricated and heat-treated Co-Cr alloy shows comparable or more porcelain adherence than cast specimens.


Assuntos
Cerâmica/química , Ligas de Cromo/química , Cobalto/química , Temperatura Alta/efeitos adversos , Lasers/efeitos adversos , Ligas Metalo-Cerâmicas/química , Análise de Variância , Colagem Dentária , Técnica de Fundição Odontológica , Porcelana Dentária/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração
9.
J Am Soc Nephrol ; 27(8): 2357-69, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26869006

RESUMO

Low cell retention and engraftment after transplantation limit the successful application of stem cell therapy for AKI. Engineered microenvironments consisting of a hydrogel matrix and growth factors have been increasingly successful in controlling stem cell fate by mimicking native stem cell niche components. Here, we synthesized a bioactive hydrogel by immobilizing the C domain peptide of IGF-1 (IGF-1C) on chitosan, and we hypothesized that this hydrogel could provide a favorable niche for adipose-derived mesenchymal stem cells (ADSCs) and thereby enhance cell survival in an AKI model. In vitro studies demonstrated that compared with no hydrogel or chitosan hydrogel only, the chitosan-IGF-1C hydrogel increased cell viability through paracrine effects. In vivo, cotransplantation of the chitosan-IGF-1C hydrogel and ADSCs in ischemic kidneys ameliorated renal function, likely by the observed promotion of stem cell survival and angiogenesis, as visualized by bioluminescence imaging and attenuation of fibrosis. In conclusion, IGF-1C immobilized on a chitosan hydrogel provides an artificial microenvironment for ADSCs and may be a promising therapeutic approach for AKI.


Assuntos
Injúria Renal Aguda/terapia , Fator de Crescimento Insulin-Like I/administração & dosagem , Transplante de Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Animais , Quitosana , Terapia Combinada , Hidrogel de Polietilenoglicol-Dimetacrilato , Camundongos
10.
Bioprocess Biosyst Eng ; 40(11): 1581-1587, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28721445

RESUMO

Efficient utilization (over needless disposal) of biorefinery pre-hydrolysate is an economically relevant practice for improving biorefinery financial prospects. The liquid fraction obtained after acid hydrolysis pretreatment of lignocellulosic biomass, called pre-hydrolysate, are predominantly comprised of hemicellulosic carbohydrates. Using a two-step bioprocess, the hexoses were selectively fermented to ethanol by S. cerevisiae to clear the path for Gluconobacter oxydans transformation of pentoses to a high purity pentonic acids solution. Finally, approximately 180 g pentonic acids and 19 g ethanol could be produced starting from pre-hydrolysate produced from 1 kg corn stover. The results demonstrate execution of our objective to prove this bioconversion method for producing high purity pentonic acids starting from crude lignocellulosic pre-hydrolysate, a wastefully disregarded biorefinery process stream.


Assuntos
Lignina/metabolismo , Pentoses/metabolismo , Biomassa , Técnicas de Cocultura , Fermentação , Gluconobacter oxydans/metabolismo , Hidrólise , Cinética , Saccharomyces cerevisiae/metabolismo
11.
J Food Sci Technol ; 54(12): 3908-3916, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085133

RESUMO

Fresh tea leaves were crushed into juice and then fermented (oxidation) to obtain fermented black tea juice, which can be used to prepare black tea beverage. The effects of addition of oolong tea infusion or tossing of tea leaves on the sensory quality and theaflavins (TFs) concentration of fermented black tea juice were investigated. The results showed that both addition of tea infusion and tossing of fresh tea leaves increased the TFs/thearubigins (TRs) ratio and improved the sensory quality of fermented black tea juice. The TFs/TRs ratio was found to be significantly correlated with the scores for flavor (r = 0.98), mouth feel (r = 0.94), and overall acceptability (r = 0.91) of the fermented black tea juices from different processes. This result suggested that a relatively high concentration of catechins and stepwise enzymatic oxidation were the crucial factors that increased the TFs/TRs ratio and improved the sensory quality. The combination of adding tea infusion and tossing fresh tea leaves greatly improved the quality of the fermented black tea juice by markedly increasing the TFs/TRs ratio (87%). Results of the present study provided useful information for improving the quality of fermented black tea juice.

12.
Med Sci Monit ; 22: 4037-4045, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27789903

RESUMO

BACKGROUND The aim of this study was to investigate the proliferation, differentiation, and tube formation of human outgrowth endothelial progenitor cells (OECs) cultured with porous demineralized bone matrix (DBM) under a dynamic perfusion system in vitro. MATERIAL AND METHODS OECs were isolated, expanded, characterized, eGFP-transfected and seeded on DBM scaffold and cultured under static or dynamic perfusion conditions, and continuously observed under fluorescence microscope. DBM scaffolds were harvested on day six for RT-PCR and western blot assay to analyze the mRNA and protein expression level of CD34, VE-cadherin, and VEGF. Scanning electron microscope (SEM) was used to observe the tube formation of OECs seeded on DBM scaffolds. RESULTS The results showed the cell density of OECs on DBM was higher when exposed to shear stress generated by a dynamic perfusion system. Shear stress also markedly increased the expression level of VE-cadherin and VEGF and decreased the expression of CD34, at both mRNA and protein levels. SEM showed that the shear-stressed OECs formed tube-like structures inside the pores of DBM scaffolds. CONCLUSIONS A dynamic perfusion system can be used as an innovative method for the rapid vascularization in tissue engineering, which can accelerate the proliferation and differentiation of OECs and the vascularization of implanted scaffolds.


Assuntos
Técnicas de Cultura de Células/métodos , Células Progenitoras Endoteliais/citologia , Engenharia Tecidual/métodos , Materiais Biocompatíveis , Matriz Óssea/citologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Células Progenitoras Endoteliais/transplante , Humanos , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/fisiologia , Osteogênese/fisiologia , Perfusão , Estresse Mecânico , Alicerces Teciduais
13.
Nanotechnology ; 26(12): 125301, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25742874

RESUMO

This paper presents a novel microelectrode arrays using high-temperature grown vertically aligned carbon nanotubes (CNTs) integrated on a flexible and biocompatible parylene substrate. A simple microfabrication process is proposed to unite the high quality vertical CNTs grown at high temperature with the heat sensitive parylene substrate in a highly controllable manner. Briefly, the CNTs electrode is encapsulated by two layers of parylene and the device is released using xenon difluoride (XeF2). The process is compatible with wafer-scale post complementary metal oxide semiconductor integration. Lower impedance and larger interfacial capacitance have been demonstrated using CNTs compared to a Pt electrode. The flexible CNT electrodes have been utilized for extracellular neuronal recording and stimulation in rats. The signal-to-noise ratio of the device is about 12.5. The threshold voltage for initiating action potential is about 0.5 V.


Assuntos
Materiais Biocompatíveis/química , Eletrodos Implantados , Microeletrodos , Nanotubos de Carbono/química , Polímeros/química , Xilenos/química , Animais , Impedância Elétrica , Estimulação Elétrica , Eletricidade , Temperatura Alta , Neuroestimuladores Implantáveis , Masculino , Teste de Materiais , Nanotubos de Carbono/ultraestrutura , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley
14.
Bioprocess Biosyst Eng ; 37(11): 2215-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24798375

RESUMO

The prehydrolyzate obtained from acid-catalyzed steam-exploded corn stover (ASC) mainly contains xylose and a number of inhibitory compounds that inhibit ethanol fermentation by Pichia stipitis. In this study, the effects of the ASC prehydrolyzate, specifically those of the carbohydrate-degradation products, lignin-degradation products (which were extracted from ASC prehydrolyzate using ethyl acetate), and six major phenolic compounds (added to pure-sugar media individually or in combination), on ethanol fermentation were investigated. Results indicate that the effects of the carbohydrate-degradation products were negligible (10 h delayed) compared with those of pure-sugar fermentation, whereas the effects of the lignin-degradation products were significant (52 h delayed). Meanwhile, the inhibitory effects of the major phenolic compounds were not caused by certain types of inhibitors, but were due to the synergistic effects of various inhibitors.


Assuntos
Biocombustíveis , Etanol/metabolismo , Pichia/metabolismo , Ácidos , Metabolismo dos Carboidratos , Fermentação/efeitos dos fármacos , Hidrólise , Lignina/metabolismo , Fenóis/farmacologia , Pichia/efeitos dos fármacos , Vapor , Xilose/metabolismo , Zea mays/química
15.
ScientificWorldJournal ; 2014: 124864, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25431774

RESUMO

The development of a deep wound infection in the presence of internal hardware presents a clinical dilemma. The purpose of the present study was to evaluate the treatment outcomes of vancomycin cement with other advances of surgical techniques for implant-related infection (IRI) in the tibia. This study included 217 consecutive patients who had sustained IRI of the tibia. Of them, 152 patients had soft tissue defects and the internal hardware was exposed. Repeated debridement and negative pressure assisted closure were used. All the infected internal hardware was removed. External fixations and flaps were used. Custom-made vancomycin cement was inserted into the dead space of the wounds and left in site for a month. The follow-up was from 12 months to 108 months, averaging 37.5 months. For all the 217 patients, the general osteomyelitis healing rate and bone union rate were 86.6% and 97.2%, respectively. This study shows high rates of healing of IRI in the tibia if the new advances of surgery could be effectively combined into the treatment strategy with vancomycin cement as an important treatment.


Assuntos
Antibacterianos/administração & dosagem , Cimentos Ósseos/uso terapêutico , Contaminação de Equipamentos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Tíbia , Vancomicina/administração & dosagem , Adulto , Desbridamento/métodos , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Reoperação/métodos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/diagnóstico por imagem , Infecção da Ferida Cirúrgica/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Adulto Jovem
16.
Food Chem ; 460(Pt 3): 140626, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39128363

RESUMO

Glucose-derived acids for the further production of value-added medicine, food additives, and polymers, will promote lignocellulosic biomass biorefinery industry. In response to the diversity and complexity, a new method was established by employing high performance anion exchange chromatography (HPAEC) coupled with a CarboPac™ PA200 column, for the precise and fast determination of glucose, gluconic acid, glucuronic acid, 2-ketogluconic acid, 5-ketogluconic acid and glucaric acid. Based on the analysis of tiny varieties in retention behavior, a gradient elution mode was designed and optimized for the quantitative and qualitative analysis. The protocol displayed acceptable linearity (R2 ≥ 0.995), commendable average recovery rate (95.28% âˆ¼ 99.89%), satisfactory precision (RSD% ≤ 1.5%), and sufficient resolution (R > 6). Additionally, this method was successfully applied to the high-value biorefining process, which confirmed the practicability and accuracy. The results demonstrated that HPAEC has good detection performance for glucose and its derivative acids, and provide key identification technical support for the high-value utilization of lignocellulose.


Assuntos
Biomassa , Glucose , Cromatografia por Troca Iônica/métodos , Glucose/análise , Glucose/química , Cromatografia Líquida de Alta Pressão/métodos , Lignina/química , Ácidos/análise , Ácidos/química
17.
Environ Sci Pollut Res Int ; 31(33): 45875-45886, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981966

RESUMO

The corrosion behavior of carbon steel under the coexistence of carbon dioxide and SRB was studied by means of corrosion weight loss, SEM, EDS, in situ pH test, and other methods. The results showed that Chloride ions, temperature, pH, and oxygen coexist with iron bacteria will affect the corrosion under the coexistence of CO2 and SRB, and SRB tends to grow in a favorable environment for itself, and the corrosion rate of X52N at 42 days is slightly higher than that at 21 days. However, the pitting depth increased sharply from 21.20 µm in 21 days to 39.79 µm in 42 days. So that the corrosion can be divided into two stages. First, SRB catalyze the dissolution of FeCO3, leading to local uniform corrosion. Second, SRB directly obtain electrons from the metal surface, resulting in local pitting. In addition, the environment under the stable mineralized biofilm was found to be slightly alkaline.


Assuntos
Dióxido de Carbono , Aço , Corrosão , Aço/química , Dióxido de Carbono/química , Biofilmes , Carbono/química
18.
J Cardiothorac Surg ; 19(1): 289, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745239

RESUMO

INTRODUCTION: Deep sternal wound infection (DSWI) after midline sternotomy of cardiac surgery is a challenging complication that affects the outcome of surgery. This study aims to assess the clinical effectiveness of the antibiotic-loaded bone cement fixation technique combined with bilateral pectoralis major muscle flaps tension-free management in the treatment of DSWI. METHODS: We retrospectively analyzed 5 patients with DSWI who underwent antibiotic-loaded bone cement combined with bilateral pectoralis major muscle flaps for chest wall reconstruction after sternotomy for cardiac surgery in a tertiary hospital in China from January 2020 to December 2021. The clinical and follow-up data were retrospectively analyzed. RESULTS: All patients had no perioperative mortalities, no postoperative complications, 100% wound healing, and an average hospital stay length of 24 days. The follow-up periods were from 6 to 35 months (mean 19.6 months). None of the cases showed wound problems after initial reconstruction using antibiotic-loaded bone cement combined with bilateral pectoralis major muscle flaps. CONCLUSIONS: We report our successful treatment of DSWI, using antibiotic-loaded bone cement fixation technique combined with bilateral pectoralis major muscle flaps tension-free management. The clinical and follow-up results are favorable.


Assuntos
Antibacterianos , Cimentos Ósseos , Músculos Peitorais , Esternotomia , Retalhos Cirúrgicos , Infecção da Ferida Cirúrgica , Humanos , Masculino , Esternotomia/efeitos adversos , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Estudos Retrospectivos , Cimentos Ósseos/uso terapêutico , Músculos Peitorais/cirurgia , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/cirurgia , Infecção da Ferida Cirúrgica/tratamento farmacológico , Feminino , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Esterno/cirurgia , Procedimentos de Cirurgia Plástica/métodos
19.
Carbohydr Polym ; 345: 122549, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227093

RESUMO

Osteoporosis, a prevalent skeletal disorder characterized by diminished bone density, compromised microstructure, and heightened fracture susceptibility, poses a growing public health concern exacerbated by aging demographics. Polysaccharides-based materials, derived from a diverse range of sources, exhibit exceptional biocompatibility. They possess a structure similar to the extracellular matrix, which can enhance cell adhesion in vivo, and demonstrate superior biological activity compared to artificial materials. This study delved into an in-depth examination of the various biomaterials and polysaccharide families associated with the treatment of osteoporosis. This article elucidates the benefits and attributes of polysaccharide-based materials in contrast to current clinical treatment modalities, delineating how these materials address prevalent challenges in the clinical management of osteoporosis. An overview of the prospective applications of polysaccharide-based materials in the future is also provided, as well as outlines the challenges that should be addressed prior to the clinical implementation of such materials.


Assuntos
Materiais Biocompatíveis , Osteoporose , Polissacarídeos , Osteoporose/tratamento farmacológico , Polissacarídeos/química , Polissacarídeos/uso terapêutico , Polissacarídeos/farmacologia , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos
20.
Int J Biol Macromol ; 271(Pt 2): 132530, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777005

RESUMO

Synergistically improving the mechanical and degradable properties of polylactic acid (PLA) scaffolds and endowing them with bioactivity are urgent problems to be solved in deepening their application in tissue engineering. In this work, tetracalcium phosphate (TTCP) and porous iron (pFe) were compounded by stirring and vacuum negative pressure, and then they were blended with polylactic acid and a porous scaffold (named TTCP@pFe/PLA) was prepared by selective laser sintering. On the one hand, molten polylactic acid penetrates the pores of porous iron to form an interlocking network, thereby achieving mechanical strengthening. On the other hand, the alkaline environment generated by the dissolution of tetracalcium phosphate can effectively catalyze the hydrolysis of polylactic acid to accelerate the degradation. Meanwhile, the dissolution of tetracalcium phosphate forms a local calcium-rich microenvironment, which rapidly induces apatite formation, that is, confers bioactivity on scaffolds. As a result, the TTCP@pFe/PLA scaffold exhibited a notable enhancement in mechanical strength, being 2.2 times stronger compared to the polylactic acid scaffold. More importantly, MC3T3E1 cells exhibit good adhesion, stretching, and proliferation on the composite scaffold, demonstrating good cytocompatibility. All these good properties of the TTCP@pFe/PLA scaffold indicate that it has potential applications as a novel alternative in bone tissue regeneration.


Assuntos
Fosfatos de Cálcio , Ferro , Poliésteres , Alicerces Teciduais , Poliésteres/química , Alicerces Teciduais/química , Porosidade , Camundongos , Animais , Ferro/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Engenharia Tecidual/métodos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Teste de Materiais , Fenômenos Mecânicos
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