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1.
Int Ophthalmol ; 43(12): 5079-5090, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37851139

RESUMO

PURPOSE: Fundus lesion segmentation determines the location and size of diabetes retinopathy in fundus image, which assists doctors in developing the best eye treatment plan. However, owing to the scattered distribution and the similarity of lesions, it is extremely difficult to extract representative lesions feature and accurately segment lesions area. METHODS: To solve the thorny problem, a generative adversarial network with multi-attention feature extraction is developed to segment diabetic retinopathy region. The main contributions are as follows: (1) An improved residual U-Net network combining with self-attention mechanism is designed as generative network to fully extract local and global feature of lesions while reducing the loss of key feature information. Considering the correlation between the same lesions feature of different samples, external attention mechanism is introduced in the residual U-Net network to focus on the relevant features of the same lesions in different samples throughout the entire dataset. (2) A discriminative network based on the PatchGAN structure is designed to further enhance the segmentation ability of generation network by discriminating between true and false samples. RESULTS: The proposed network is evaluated on the public dataset IDRiD, which achieved the Dice correlation coefficients of 75.7%, 76.53%, 50.06%, and 45.89% for EX, SE, MA, and HE, respectively. CONCLUSION: The experimental results show the generative adversarial neural network qualified for accurate segmentation of diabetic retinopathy from fundus image well.


Assuntos
Retinopatia Diabética , Humanos , Retinopatia Diabética/diagnóstico , Fundo de Olho , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador
2.
J Food Sci Technol ; 59(10): 4037-4044, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36193361

RESUMO

Lycopene is a highly potent antioxidant that is prevalent among dietary carotenoids. However, its use in food formulations is restricted due to its poor water-solubility and proneness to oxidation. The aim of this research was to encapsulate lycopene in yogurt using emulsion technology for improving its stability during processing and storage, in order to diversify a widely consumed food product and enhance its nutritional value. Confocal laser microscopy data showed that the incorporation of oil droplets with emulsification did not have a negative effect on the formation and microstructure of yogurt. Syneresis of lycopene-fortified yogurt samples was approximately twice as high compared with plain yogurt at day 7; the ability to retain water was significantly improved with storage time for all emulsified samples. Additionally, storage reduced the Turbiscan Stability Indices (TSI) for all yogurt samples, which suggests that physical stability improved at 4 °C. Emulsification resulted in increased oxidation levels due to increased oil content. This effect was ameliorated by lycopene encapsulation, which effectively protected corn oil from oxidation and prevented degradation. This study indicates that emulsification is a promising method for lycopene encapsulation and can be used for developing yogurt with desirable nutritional properties.

3.
Sensors (Basel) ; 18(12)2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30544725

RESUMO

Low visibility and hot smoke environment under fire conditions can largely hamper the related fire rescue processes. Ultrasound obstacle avoidance technology is then useful for guidance. However, the biggest challenge of adopting ultrasound technology comes from accurate distance measurements under the disturbances of high temperature and soot particle concentration. It is critical to measure the propagation speed under the complicated fire conditions. Therefore, in this study, a baffle calibration method was proposed to improve the accuracy of distance measurement of an obstacle. The method is based on two ultrasound measurement systems, while one is used to calibrate the propagation speed of ultrasound based on the fixed distanced baffle and the other is for the dynamic measurement of obstacle distance based on the calibrated speed. The viability of this method on the guided vehicle was confirmed based on the experiments. From its comparison to those existing methods, such as constant speed and temperature compensation methods, it was known from that the proposed baffle calibration method provides the best prediction. It was obtained that the maximum errors based on the baffle calibration method are 2.75% and 2.62% under the two representative fire scenarios, respectively, which are much lower than those of constant speed (7.81% and 8.4%) and temperature compensation methods (10.4% and 5.12%).

4.
Prep Biochem Biotechnol ; 47(6): 611-618, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28165864

RESUMO

The urban wastewater treatment industry produces a large amount of excess activated sludge which is mainly composed of microbial biomass and costly to be disposed. In this research, a comprehensive utilization of activated sludge was developed by sequentially extracting hydrolytic enzymes and polyhydroxyalkanoates (PHAs), and the residue was used to prepare water-retaining organic fertilizer. The sludge was extracted with fourfold H2O-containing 1% Triton X-100 with the yield of 66.7% protease activity. The enzyme solution was precipitated in 80% acetone and vacuum dried at 40°C at the dried enzyme yield of 2.4 g/kg wet sludge. The enzyme product contains collagenase, lipase, amylase, and cellulase activities, which are good compound enzymes to feed. The PHAs were extracted with 30% sodium hypoclorite:chloroform (1:3). The PHA solution was decolored and dried, and pure white PHAs were obtained at the yield of 70.1 g/kg wet sludge. The residue was used to prepare water-retaining organic fertilizer at the optimal condition. The fertilizer absorbs 131.3-fold distilled water and had good performance in water retention and can effectively slow down the loss of soil moisture when added into soil. This work provides a simple and practical approach for comprehensive utilizing activated sludge with significant economic benefits.


Assuntos
Fertilizantes , Peptídeo Hidrolases/isolamento & purificação , Poli-Hidroxialcanoatos/química , Polímeros/química , Esgotos/microbiologia , Fertilizantes/análise , Hidrólise , Peptídeo Hidrolases/química , Poli-Hidroxialcanoatos/isolamento & purificação , Água/química
5.
J Food Sci Technol ; 54(7): 2186-2192, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28720978

RESUMO

The lack of aroma and natural taste is a critical problem in production and consumption of instant green teas. A method to prepare instant green teas high in-natural-aroma and low-caffeine by the novel column chromatographic extraction with gradient elution is reported. This method simultaneously extracted aroma (or volatile) and non-aroma compounds from green tea. Green tea was loaded into columns with 2.0-fold of petroleum ether (PE): ethanol (8:2). After standing for 3 h until the aroma compounds dissolved, the column was sequentially eluted with 3.0-fold 40% ethanol and 3.5-fold water. The eluant was collected together and automatically separated into PE and ethanol aqueous phases. The aroma extracts was obtained by vacuum-evaporation of PE phase at 45 °C. The ethanol aqueous phase was vacuum-concentrated to aqueous and partially or fully decaffeinated with 4% or 9% charcoal at 70 °C. A regular instant green tea with epigallocatechin-3-gallate: caffeine of 3.5:1 and a low-caffeine instant green tea (less than 1% caffeine) with excellent aroma and taste were prepared, by combining the aroma and non-aroma extracts at a 1:10 ratio. This work provides a practical approach to solve the low-aroma and low-taste problems in the production of high quality instant green teas.

6.
Appl Microbiol Biotechnol ; 99(4): 1745-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25190667

RESUMO

Polyphenol oxidase (PPO) has multiple functions, and the lack of commercially available enzyme sources limits its widespread application in various industries. An accurate PPO assay was developed by HPLC determination of the substrate oxidation. Resources screening indicated that sweet potato (Ipomoea batatas L.) wastewater in starch production has high PPO activity. A procedure was developed for separately recovering PPO, ß-amylase, sporamins, and small molecular nutrients (SMNs) from sweet potato wastewater. The wastewater was adjusted to pH 3.5 to precipitate PPO, and then adjusted to 50 % acetone to precipitate ß-amylase and further to 80 % acetone to precipitate sporamins. The SMNs were obtained after acetone recovery. Purified powders of 4.3 × 10(5) units of PPO, 4.0 × 10(6) units of ß-amylase, 8.70 g sporamins, and 20.2 g SMNs were obtained from the wastewater of 1 kg sweet potato. More than 50 million tons of sweet potato is used for starch production annually around the world. Through this simple procedure, huge amount of biochemical resources can be recovered from the wastewater, which greatly increases the economic value of the crop and saves the environment.


Assuntos
Catecol Oxidase/isolamento & purificação , Ipomoea batatas/química , Amido/isolamento & purificação , Águas Residuárias/análise , Fracionamento Químico , Precipitação Química , Proteínas de Plantas/isolamento & purificação , beta-Amilase/isolamento & purificação
7.
Urol Int ; 94(1): 64-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25115358

RESUMO

INTRODUCTION: In order to anatomically reconstruct ureteral stenosis, we present a novel technique for laparoscopic ureteral reimplantation. PATIENTS AND METHODS: Three young females, who were diagnosed with hydroureteronephrosis caused by congenital vesicoureteral junction obstruction, were treated by laparoscopic ureteral reimplantation with a tunnel underneath the broad ligament. RESULTS: Surgery was performed successfully without conversion to open surgery. No major intra- or postoperative complications occurred. Postoperative follow-up was 38, 33 and 26 months, respectively. The operative time was between 220 and 260 min. The mean estimated blood loss was less than 20 ml. Subsequent imaging performed 3 months after surgery revealed relief of hydroureteronephrosis for all patients. The patients all gave birth to healthy neonates and showed normal urinary tract sonogram and urine analysis during the gestation period. CONCLUSION: Laparoscopic ureteral reimplantation with broad ligament tunnel is safe and effective, allowing for anatomical reconstruction of ureter defects. However, a larger clinical sample and longer follow-up period will be needed.


Assuntos
Laparoscopia , Ligamentos/cirurgia , Reimplante , Ureter/cirurgia , Obstrução Ureteral/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adulto , Perda Sanguínea Cirúrgica , Feminino , Humanos , Laparoscopia/efeitos adversos , Nascido Vivo , Duração da Cirurgia , Gravidez , Reimplante/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Ureter/anormalidades , Obstrução Ureteral/congênito , Obstrução Ureteral/diagnóstico , Procedimentos Cirúrgicos Urológicos/efeitos adversos , Adulto Jovem
8.
J Foot Ankle Surg ; 54(1): 76-81, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25441282

RESUMO

The aim of the present study was to investigate the outcomes of surgical treatment of calcaneal fractures of Sanders type II and III using a minimally invasive technique and a locking plate. We reviewed 33 feet in 33 consecutive patients with Sanders type II and III calcaneal fractures who had undergone a minimally invasive technique using percutaneous reduction and locking plates. All operations were performed by the same surgeons. The postoperative evaluation included radiographs, determination of restoration of Böhler's angle and Gissane's angle, and administration of the American Orthopaedic Foot and Ankle Society ankle-hind foot scale, Maryland Foot Score, and visual analog scale of pain. The mean visual analog scale score was 1.6 ± 1.4 when radiographic fracture healing was observed. The median functional score of the 33 patients (33 feet) reached 82 (interquartile range 80 to 99) at the last follow-up evaluation according to the American Orthopaedic Foot and Ankle Society ankle-hind foot scale and 89 (interquartile range 80 to 99) according to Maryland Foot Score. All cases achieved restoration of a normal Böhler's angle and Gissane's angle. Postoperative superficial infections occurred in 2 patients, subtalar arthritis developed in 2, and no soft tissue necrosis was observed. For Sanders type II and III fractures of the calcaneus bone, treatment with a minimally invasive technique combining percutaneous reduction and locking plate fixation provided satisfactory clinical results, with a lower incidence of complications. However, longer term studies with a larger sample size and more randomized controlled trials are required to define the superiority of our minimally invasive technique compared with conventional surgical treatment of calcaneal fractures.


Assuntos
Calcâneo/cirurgia , Traumatismos do Pé/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Intra-Articulares/cirurgia , Adulto , Placas Ósseas , Calcâneo/diagnóstico por imagem , Calcâneo/lesões , Feminino , Traumatismos do Pé/diagnóstico por imagem , Fixação Interna de Fraturas/instrumentação , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Prospectivos , Radiografia , Resultado do Tratamento , Adulto Jovem
9.
Chin J Traumatol ; 17(2): 63-8, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24698572

RESUMO

OBJECTIVE: To compare the clinical effects between closed reduction and internal fixation (CRIF) and total hip arthroplasty (THA) for displaced femoral neck fracture. METHODS: In this prospective randomized study, 285 patients aged above 65 years with hip fractures (Garden III or IV) were included from January 2001 to December 2005. The cases were randomly allocated to either the CRIF group or THA group. Patients with pathological fractures (bone tumors or metabolic bone disease), preoperative avascular necrosis of the femoral head, osteoarthritis, rheumatoid arthritis, hemiplegia, long-term bed rest and complications affecting hip functions were excluded. RESULTS: During the 5-year follow-up, CRIF group had significantly higher rates of complication in hip joint, general complication and reoperation than THA group (38.3% vs. 12.7%, P<0.01; 45.3% vs. 21.7%, P<0.01; 33.6% vs. 10.2%, P<0.05 respectively). There was no difference in mortality between the two groups. Postoperative function of the hip joint in THA group recovered favorably with higher Harris scores. CONCLUSION: For displaced fractures of the femoral neck in elderly patients, THA can achieve a lower rate of complication and reoperation, as well as better postoperative recovery of hip joint function compared with CRIF.


Assuntos
Artroplastia de Quadril/métodos , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Colo Femoral/fisiopatologia , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Falha de Tratamento , Caminhada
10.
Phytochem Anal ; 24(6): 623-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23722924

RESUMO

INTRODUCTION: Camptothecin, a widely used natural anti-cancer drug, is difficult to extract and purify effectively from plants. OBJECTIVE: To develop new and highly efficient extraction and purification methods for analysis and production of camptothecin from leaves and fruits of Camptotheca acuminata and Nothapodytes pittosporoides roots. METHODS: Dried materials were loaded in empty columns with fivefold 60% ethanol for leaves or 70% ethanol for fruits of C. acumnata, and sixfold 70% ethanol for N. pittosporoides roots. The columns were eluted with the same solvents at room temperature. Eluent was collected as extraction solution. Extraction solution from leaves and fruits of C. acuminata was vacuum-evaporated to remove ethanol, precipitated at pH 8.0 to remove alkaline insolubles and fractionated with chloroform at pH 3.0, which yields a crude product with 70% purity. Extraction solution from N. pittosporoides roots was concentrated to 1/10 volume and precipitated at pH 3.0, which yields a crude product with 60% purity. All crude products were purified by crystallisation. All steps were monitored by HPLC. RESULTS: Camptothecin was extracted from the three plant materials at a 98% rate with 15- or 18-fold solvent for content analysis, or at a 97% rate with five- or sixfold solvent for production. All crude products were purified to 98%. The overall recovery rates of camptothecin from plant materials to purified products reached 92% or higher. CONCLUSION: The new procedures are simple and highly efficient, and have multiple advantages for quantitative analysis and large production of camptothecin from plants.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Camptotheca/química , Camptotecina/isolamento & purificação , Cromatografia/métodos , Cromatografia/normas , Folhas de Planta/química , Raízes de Plantas/química
11.
Burns ; 49(1): 169-181, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35361497

RESUMO

To overcome limited donor-site availability in patients with extensive burns, split-thickness skin grafts (STSGs) are sometimes minced into micrografts (MGs) to improve the expansion ratio of the grafts, but this may reduce wound healing. We aimed to produce a novel hydrogel as an overlay of minced STSGs to improve wound healing. The new hydrogel was produced using recombinant human collagen type III powder as a raw material. Morphological and physical characteristics (degradation and swelling rate), cytotoxicity, and cell viability of the hydrogel were evaluated in vitro. A full-thickness in vivo skin defect model was constructed with male Sprague-Dawley rats. The animals were randomly assigned to experimental and control groups in which the new hydrogel and Vaseline gauze, respectively, were overlaid on minced STSGs to repair and regenerate skin wound. The healing rates and recovery status were compared between the two groups. The hydrogels exhibited good water retention properties and a suitable degradation rate, which can promote the proliferation and migration of wound healing-related cells in vitro. Further, using the hydrogel as an overlay accelerated wound closure and angiogenesis, increased dermal tissue and basement membrane formation, enhanced collagen synthesis and wound healing-related growth factor expression, while reducing scar formation compared to the Vaseline gauze group. In conclusion, the novel, low-cost recombinant human collagen hydrogel can accelerate wound closure and improve wound healing when used as an overlay of minced STSGs. The new hydrogel could become a new treatment option for traumatic skin wounds caused by burns or injuries.


Assuntos
Queimaduras , Lesões dos Tecidos Moles , Animais , Humanos , Masculino , Ratos , Queimaduras/cirurgia , Colágeno , Hidrogéis/farmacologia , Ratos Sprague-Dawley , Pele/lesões , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Cicatrização
12.
Polymers (Basel) ; 15(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36904434

RESUMO

The thermal protection performance of fire suit is vital to the safety of firefighters. Using certain physical properties of fabrics to evaluate their thermal protection performance speeds up the process. This work aims to develop a TPP value prediction model that can be easily applied. Five properties of three types of Aramid 1414 made of the same material were tested, and the relationships between the physical properties of Aramid 1414 and its thermal protection performance (TPP value) were investigated. The results showed that the TPP value of the fabric had a positive correlation with grammage and air gap, and a negative correlation with the underfill factor. A stepwise regression analysis was used to solve the collinearity issue between the independent variables. Finally, a model for predicting TPP value by air gap and underfill factor was developed. The method adopted in this work reduced the number of independent variables in the prediction model, which is conducive to the application of the model.

13.
BMJ Nutr Prev Health ; 6(1): 21-27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37559968

RESUMO

Objectives: Even though disinfectants are commonly used in clinical practice and daily life, there are few studies on their antibacterial ability and cytotoxicity, which are closely related to the safety and effectiveness of their use. To provide a basis for the use of disinfectants, the cytotoxicity and antibacterial activity of three most commonly used disinfectants, povidone-iodine, chlorhexidine acetate and polyhexamethylene biguanide (PHMB), were investigated. Design: A CCK-8 assay was used to measure the activities of human fibroblasts (HF) and keratinocytes (HaCat), the two most important cells in wound healing, following their exposure to disinfectants. The effects of different times and concentrations were included. The antibacterial activity of disinfectants against Staphylococcus aureus, Acinetobacter baumannii, Klebsiella pneumoniae was reflected by their minimum inhibitory concentration and minimum bactericidal concentration. Results: All three disinfectants showed strong cytotoxicity in direct contact with HF and HaCat cells. Cytotoxicity increased with increasing exposure time and concentration. S. aureus, A. baumannii and K. pneumoniae comprised 70%, 55% and 85% of the strains sensitive to povidone iodine; 50%, 45% and 80% of the strains sensitive to chlorhexidine acetate; and 60%, 45% and 80% of the strains sensitive to PHMB, respectively. Conclusions: All three disinfectants were cytotoxic; therefore, it is necessary to pay attention to the use time and concentration in the clinical setting. All three disinfectants were cytotoxic, with povidone-iodine being the most cytotoxic even at low concentrations. PHMB had better antibacterial efficacy against S. aureus and is suitable for the treatment of shallow wounds primarily. All three tested bacteria were significantly more sensitive to PHMB than to the other disinfectants.

14.
Sci Rep ; 13(1): 8380, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225720

RESUMO

It is important to explore the effective approaches to prevent dry age-related macular degeneration (AMD). In this study, significantly decreased full-field electroretinograms wave amplitudes and disordered retina structures were detected in rat retinas of sodium iodate induced dry AMD model. Six a- and b-wave amplitudes and the antioxidant activities were significantly increased, and the outer nuclear layer thickness was significantly improved in the rat retinas treated with the combination of Lactobacillus fermentum NS9 (LF) and aronia anthocyanidin extract (AAE) compared with the model. The effects were much better than the treatment with AAE alone. The proteomics analysis showed the expressions of α-, ß- and γ-crystallins were increased by 3-8 folds in AAE treated alone and by 6-11 folds in AAE + LF treatment compared with the model, which was further confirmed by immuno-blotting analysis. Analysis of gut microbial composition indicated that higher abundance of the genus Parasutterella and species P. excrementihominis was found in the AAE + LF treatment compared with the other groups. The results indicated that the combined treatment of AAE + LF is a potential way to prevent the retina degeneration which is significantly better than the AAE treated alone.


Assuntos
Atrofia Geográfica , Limosilactobacillus fermentum , Photinia , Degeneração Retiniana , Animais , Ratos , Antocianinas/farmacologia , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/prevenção & controle , Retina , Extratos Vegetais/farmacologia
15.
Int J Biol Macromol ; 236: 123943, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889621

RESUMO

The disadvantages of mainstream therapies for endometrial injury are difficult to resolve, herein, we suggest an omnibearing improvement strategy by introducing an injectable multifunctional self-assembled dual-crosslinked sodium alginate/recombinant collagen hydrogel. The hydrogel possessed a reversible and dynamic double network based on dynamic covalent bonds and ionic interactions, which also contributed to excellent capability in viscosity and injectability. Moreover, it was also biodegradable with a suitable speed, giving off active ingredients during the degradation process and eventually disappearing completely. In vitro tests exhibited that the hydrogel was biocompatible and able to enhance endometrial stromal cells viability. These features synergistically promoted cell multiplication and maintenance of endometrial hormone homeostasis, which accelerated endometrial matrix regeneration and structural reconstruction after severe injury in vivo. Furthermore, we explored the interrelation between the hydrogel characteristics, endometrial structure, and postoperative uterine recovery, which would benefit deep research on regulation of uterine repair mechanism and optimization of hydrogel materials. The injectable hydrogel could achieve favourable therapeutic efficacy without the need of exogenous hormones or cells, which would be of clinical value in endometrium regeneration.


Assuntos
Alginatos , Hidrogéis , Feminino , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Alginatos/química , Endométrio , Colágeno , Útero
16.
Plant Cell Rep ; 31(1): 121-31, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21932029

RESUMO

A resveratrol synthase gene was cloned from the peanut plant (Arachis hypogaea) by RT-PCR and was transformed into purple sweet potato (Ipomoea batatas) by Agrobacterium-mediated transformation. Stem sections were infected with bacterial solution of OD(600) = 0.4 for 20 min and then cocultured for 2 days. Infected explants were cultured on MS media containing 50 mg/l kanamycin, 0.02 mg/l NAA and 1 mg/l 6-BA for bud induction or containing 75 mg/l kanamycin, 1.0 mg/l NAA and 0.1 mg/l 6-BA for root formation. The bud and root induction rates were 37.5 and 25.0%, respectively. 105 regenerated plants were obtained, with 11 positive plants by PCR and Southern blotting analyses. A high level of resveratrol glucoside (340 µg/g dry weight), but no resveratrol, was detected in the transformed plants by HPLC. This study also provides a stable genetic transformation and plant regeneration method for metabolic modification of purple sweet potato.


Assuntos
Aciltransferases/genética , Arachis/genética , Ipomoea batatas/genética , Aciltransferases/metabolismo , Agrobacterium/genética , Clonagem Molecular , Meios de Cultura/química , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Canamicina/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Resveratrol , Análise de Sequência , Estilbenos/análise , Estilbenos/metabolismo , Transformação Genética
17.
Sci Rep ; 12(1): 13223, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918356

RESUMO

Crocodiles are cultured in large numbers in Asia and other places in order to protect wild resources and meet the needs of human life. In this study, crocodile (Crocodylus siamensis) meat proteins were extracted and hydrolyzed into peptides, their antioxidant peptides were isolated and purified by silica gel chromatography and identified by LC/MS. Crocodile meat proteins were optimally extracted with water and hydrolyzed by papain based on the degree of hydrolysis and antioxidant activity. The hydrolysates were fractionated by ultrafiltration into 3 kDa, 3-30 kDa, and ≥ 30 kDa fractions. The 3 kDa fraction showed most antioxidant activity of the hydrolysates. Its active peptides were separated by silica gel column chromatography and purified by silica gel TLC, based on TLC bio-autographic assays of the activity. Four highly active peptides were identified by LC/MS as SSLTIQFVEGQFVDSYDPTIENTFTK, VPPHIY, VAPEEHPVLLTEAPLNPK, and RNGLPGPIGPAG. The identified peptides were synthesized and showed 50% free radical scavenging activities at 1.0 mg/mL, equal or higher to ascorbic acid at 0.5 mg/mL, in both DPPH and ABTS assays. The results indicated that the 3 kDa hydrolyzed peptides of crocodile meat had high antioxidant activity and the active peptides can be effectively separated and purified by silica gel column chromatography and TLC.


Assuntos
Jacarés e Crocodilos , Antioxidantes , Animais , Antioxidantes/química , Cromatografia em Gel , Humanos , Hidrólise , Carne , Proteínas de Carne , Peptídeos/química , Hidrolisados de Proteína/química , Sílica Gel , Dióxido de Silício
18.
Int J Oral Sci ; 14(1): 51, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316311

RESUMO

With the emergence of DNA nanotechnology in the 1980s, self-assembled DNA nanostructures have attracted considerable attention worldwide due to their inherent biocompatibility, unsurpassed programmability, and versatile functions. Especially promising nanostructures are tetrahedral framework nucleic acids (tFNAs), first proposed by Turberfield with the use of a one-step annealing approach. Benefiting from their various merits, such as simple synthesis, high reproducibility, structural stability, cellular internalization, tissue permeability, and editable functionality, tFNAs have been widely applied in the biomedical field as three-dimensional DNA nanomaterials. Surprisingly, tFNAs exhibit positive effects on cellular biological behaviors and tissue regeneration, which may be used to treat inflammatory and degenerative diseases. According to their intended application and carrying capacity, tFNAs could carry functional nucleic acids or therapeutic molecules through extended sequences, sticky-end hybridization, intercalation, and encapsulation based on the Watson and Crick principle. Additionally, dynamic tFNAs also have potential applications in controlled and targeted therapies. This review summarized the latest progress in pure/modified/dynamic tFNAs and demonstrated their regenerative medicine applications. These applications include promoting the regeneration of the bone, cartilage, nerve, skin, vasculature, or muscle and treating diseases such as bone defects, neurological disorders, joint-related inflammatory diseases, periodontitis, and immune diseases.


Assuntos
Ácidos Nucleicos , Ácidos Nucleicos/química , Medicina Regenerativa , Consenso , Reprodutibilidade dos Testes , DNA/química
19.
Int J Bioprint ; 8(2): 517, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669327

RESUMO

Artificial skins are biomaterials that can replace the lost skin or promote the regeneration of damaged skin. Skin regenerative biomaterials are highly applauded because they can exempt patients with severe burns from the painful procedure of autologous skin transplantation. Notwithstanding decades of research, biocompatible, degradable, and printable biomaterials that can effectively promote skin regeneration as a transplantation replacement in clinical use are still scarce. Here, we report one type of all-protein hydrogel material as the product of the enzymatic crosslinking reaction of gelatin and a recombinant type III collagen (rColIII) protein. Doping the rColIII protein in gelatin reduces the inflammatory response as an implant underneath the skin. The all-protein hydrogel can be bioprinted as scaffolds to support the growth and proliferation of 3T3 fibroblast cells. The hydrogel used as a wound dressing promotes wound healing in a rat model of skin damage, showing a faster and healthier recovery than the controls. The rColIII protein in the hydrogel has been shown to play a critical role in skin regeneration. Altogether, this work manifests the development of all-protein gelatin-rColIII hydrogel and demonstrates its use in wound healing. The gelatin-collagen hydrogel wound dressing thereby may become a promising treatment of severe wounds in the future.

20.
Int J Biol Macromol ; 217: 55-65, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35817243

RESUMO

Infection-induced chronic wounds cause prolonged pains, a high risk of amputation, and even increased mortality in immunocompromised patients. Here we report an antibacterial microneedle (MN) patch, which features high degradability in biological fluids and gelatinase-responsive release of an antibacterial photothermal peptide AMP-Cypate. We first synthesize gelatin nanoparticles (GNPs) and then conjugate the AMP-Cypate to afford composite AMP-Cypate@GNPs. The proteinaceous nanoparticles can responsively release AMP-Cypate in the presence of gelatinase, an enzyme secreted specifically by Staphylococcus aureus (S. aureus). AMP-Cypate@GNPs were then deposited in the tips of MNs fabricated by PVP and recombinant human type III collagen (Col III) to devise the antibacterial MN/AMP-Cypate@GNP patches. When applied to the infection site, MNs break through the epidermis and the stratum corneum, dissolve in the infected dermis, reach the bacterial colony or biofilm, release AMP-Cypate@GNPs, and exert a gelatinase-responsive photothermal therapy under near-infrared (NIR) irradiation to kill the pathogen S. aureus. In a rat model of staphylococcal infection-induced chronic wounds mimicking the condition of diabetic foot ulcer, the antibacterial MN/AMP-Cypate@GNP patches eradiated the bacterial infection and resulted in complete healing of the wounds, proving its potential application in the treatment of chronic wound infections and diabetic foot ulcers.


Assuntos
Pé Diabético , Nanopartículas , Infecções Estafilocócicas , Animais , Humanos , Ratos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Doença Crônica , Gelatina , Gelatinases , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus
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