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1.
Quant Imaging Med Surg ; 14(3): 2426-2440, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38545081

RESUMO

Background: Capturing the segmentation of blood vessels by a fundus camera is crucial for the medical evaluation of various retinal vascular issues. However, due to the complicated vascular structure and unclear clinical criteria, the precise segmentation of blood arteries remains very challenging. Methods: To address this issue, we developed the upgraded multi-convolution block and squeeze and excitation based on the U-shape network (MCSE-U-net) model that segments retinal vessels using a U-shaped network. This model uses multi-convolution (MC) blocks, squeeze and excitation (SE) blocks, and squeeze blocks. First, the input image was processed using the luminance, chrominance-blue, chrominance-red (YCbCr) color conversion method to further improve visibility. Second, a MC module was added to increase the model's ability to accurately segment blood vessels. Third, SE blocks were added to enhance the network model's ability to segment fine blood vessels in medical images. Results: The suggested architecture was assessed using evaluation metrics, including the Dice coefficient, sensitivity (sen), specificity (spe), accuracy (acc), and mean intersection over union (mIoU), on an open-source Digital Retinal Images for Vessel Extraction (DRIVE) data set. The outcomes showed the effectiveness of the suggested approach, particularly in the extraction of peripheral vascular anatomy. Using the suggested architecture, the model had a Dice coefficient of 0.8430, a sen of 0.8752, a spe of 0.9902, an acc of 0.9725, and a mIoU of 0.8473 for the DRIVE data set. The Dice coefficient, sen, spe, acc, and mIoU of the MCSE-U-net increased by 3.08%, 6.22%, 0.62%, 0.61%, and 3.01%, respectively, compared to the original U-net, demonstrating the better all-around performance of the MCSE-U-net. Conclusions: The MCSE-U-net network performed and achieved more than the technologies already in use.

3.
Neurobiol Aging ; 72: 159-170, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30273830

RESUMO

Mutations in fused in sarcoma (Fus) cause familial amyotrophic lateral sclerosis (ALS) and occasionally frontotemporal dementia. Here we report the establishment and characterization of a novel knockin (KI) rat model expressing a Fus point mutation (R521C) via CRISPR/Cas9. The mutant animals developed adult-onset learning and memory behavioral deficits, with reduced spine density in hippocampal neurons. Remarkably, sleep-wake cycle and circadian abnormalities preceded the onset of cognitive deficit. RNA-seq study further demonstrated altered expression of some key sleep and circadian regulators, such as orexin/hypocretin receptor type 2 and casein kinase 1 epsilon, in the mutant rats. Therefore, we have established a rodent model expressing physiological level of a pathogenic mutant FUS, and we found cognitive impairment as a main behavioral deficit at mid age. Furthermore, we have revealed a new role of FUS in sleep and circadian regulation and demonstrated that functional change in FUS could cause sleep-wake and circadian disturbance as early symptoms.


Assuntos
Comportamento Animal , Transtornos Cronobiológicos/genética , Disfunção Cognitiva/genética , Proteína FUS de Ligação a RNA/metabolismo , Sono/genética , Vigília/genética , Fatores Etários , Animais , Células Cultivadas , Modelos Animais de Doenças , Eletroencefalografia , Eletromiografia , Embrião de Mamíferos , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Transtornos do Sono do Ritmo Circadiano/genética
4.
Urol J ; 14(4): 4055-4061, 2017 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-28670676

RESUMO

Ureteric substitution using the Yang-Monti principle was reported as a modification of simple ileal ureter replacement. During April 2013 to June in 2015, 2 patients underwent ileal ureteral substitution using a reconfigured ileal segment of Yang Monti principle in our clinical center. Some slight modifications were made and then follow-up were carried out up to 12 months. For these 2 cases, no significant intra/post-operative complications occurred. In 1 year follow up, serum creatinine (Scr) and blood urea nitrogen (BUN) of both patients decreased to normal.Glomerular filtration rate (GFR), renogram and pyelogram showed a stable split renal function. To better understand the Yang-Monti principle and potential risks and complications, we conduct an systemic review by searching PubMed, Google Scholar and the Cochrane Library database from January 1996 through June 2016. 10 out of 644 publications were identified, which included 269 patients from cohort studies. The most usual indications for Yang-monti therapy were iatrogenic stricture and retroperitoneal fibrosis. Infection and ileus were indicated as themain short time postoperative complications while the fistula and re- strictures happened in long-term. In general,we believe Yang-Monti Principle is a safer and efficient technique for clinical partial and complete ureteral defects if patients and potential risks could be well prepared.


Assuntos
Íleo , Procedimentos de Cirurgia Plástica , Ureter , Obstrução Ureteral , Adulto , Idoso , Feminino , Humanos , Masculino , Íleo/transplante , Procedimentos de Cirurgia Plástica/métodos , Ureter/cirurgia , Obstrução Ureteral/cirurgia
5.
Sci Rep ; 6: 31593, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27531588

RESUMO

In treatment of diabetes, it is much desired in clinics and challenging in pharmaceutics and material science to set up a long-acting drug delivery system. This study was aimed at constructing a new delivery system using thermogelling PEG/polyester copolymers. Liraglutide, a fatty acid-modified antidiabetic polypeptide, was selected as the model drug. The thermogelling polymers were presented by poly(ε-caprolactone-co-glycolic acid)-poly(ethylene glycol)-poly(ε-caprolactone-co-glycolic acid) (PCGA-PEG-PCGA) and poly(lactic acid-co-glycolic acid)-poly(ethylene glycol)-poly(lactic acid-co-glycolic acid) (PLGA-PEG-PLGA). Both the copolymers were soluble in water, and their concentrated solutions underwent temperature-induced sol-gel transitions. The drug-loaded polymer solutions were injectable at room temperature and gelled in situ at body temperature. Particularly, the liraglutide-loaded PCGA-PEG-PCGA thermogel formulation exhibited a sustained drug release manner over one week in both in vitro and in vivo tests. This feature was attributed to the combined effects of an appropriate drug/polymer interaction and a high chain mobility of the carrier polymer, which facilitated the sustained diffusion of drug out of the thermogel. Finally, a single subcutaneous injection of this formulation showed a remarkably improved glucose tolerance of mice for one week. Hence, the present study not only developed a promising long-acting antidiabetic formulation, but also put forward a combined strategy for controlled delivery of polypeptide.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Liraglutida/administração & dosagem , Polímeros/administração & dosagem , Animais , Glicemia/metabolismo , Géis , Teste de Tolerância a Glucose , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/uso terapêutico , Liraglutida/farmacocinética , Liraglutida/uso terapêutico , Camundongos , Camundongos Endogâmicos ICR
6.
Biomater Sci ; 2(8): 1100-1109, 2014 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32482005

RESUMO

Post-surgical peritoneal adhesions constitute a classic problem in surgery, and thus anti-adhesion materials are much required. In this study, a series of polyester-PEG-polyester triblock copolymers with different biodegradable polyester compositions were synthesized, their properties were examined, and the in vivo efficacies as anti-adhesion biomaterials were evaluated in a comparative way for the first time. These samples not only exhibited various morphologies in the bulk state, but also possessed different stabilities in the sol state. All the polymer aqueous solutions with appropriate compositions and concentrations underwent sol-gel transitions with increase of temperature and formed semi-solid hydrogels at body temperature. The efficacy of PEG/polyester thermogels (25 wt%) for preventing post-operative abdominal adhesions was investigated and compared in a rabbit model of sidewall defect-bowel abrasion. Different efficacies of anti-adhesion were observed, possible mechanisms were discussed, and the importance of viscoelasticity was suggested for the first time. These results illustrated that appropriate properties of PEG/polyester thermogels including viscoelastic matrix, hydrophilic surface and moderate in vivo persistence played crucial roles in enabling an effective device to prevent post-surgical peritoneal adhesions.

7.
Int Orthop ; 37(3): 515-21, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23180106

RESUMO

PURPOSE: The aim of this study was to determine whether hydroxypropylcellulose (HPC) coating of polyethylene terephthalate (PET) artificial ligaments enhances graft osseointegration in the bone tunnel. METHODS: Thirty New Zealand white rabbits underwent artificial ligament graft transplantation in the bilateral proximal tibia tunnels. One limb was implanted with an HPC-coated PET graft, and the contralateral limb was implanted with a non-HPC-coated PET graft as a control. The rabbits were then randomly sacrificed at weeks four and eight after surgery for biomechanical testing, histological examination, and histomorphometric and real-time polymerase chain reaction analysis. RESULTS: At week four after surgery, there were no statistically significant differences in the load to failure or stiffness values between the experimental and control limbs (P = 0.328 and P = 0.128, respectively). At week eight after surgery, the mean load to failure and stiffness value of the experimental limbs was higher than that of the control limbs (P < 0.001 and P = 0.018, respectively). At week eight after surgery, some protruding new bone tissue from the host bone to the graft was found in the HPC-coated group, while a thick fibrous tissue band was observed at the interface between the graft and the host bone in the control group. Histomorphometric analysis showed that the graft-bone interface width in the HPC-coated group was significantly narrower than that in the control group at week eight after surgery (P < 0.001). At weeks four and eight after surgery, the mRNA expression level of bone morphogenetic protein-2 in the HPC group was higher than that in the control group (P = 0.001 and P = 0.010, respectively). The mRNA expression level of osteopontin in the HPC group was higher than that in the control group only at week four after surgery (P = 0.032). CONCLUSIONS: Our data show that an HPC coating on the surface of PET artificial ligament grafts may induce artificial ligament graft osseointegration in the bone tunnel.


Assuntos
Celulose/análogos & derivados , Ligamentos/transplante , Osseointegração/efeitos dos fármacos , Tíbia/cirurgia , Animais , Celulose/farmacologia , Materiais Revestidos Biocompatíveis , Modelos Animais de Doenças , Masculino , Polietilenotereftalatos , Próteses e Implantes , Coelhos
8.
Biotechnol Lett ; 35(4): 657-61, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23247568

RESUMO

A novel hydroxyapatite/regenerated silk fibroin scaffold was prepared and investigated for its potential to enhance both osteoinductivity and osteoconductivity of bone marrow-derived mesenchymal stromal cells in vitro. Approx. 12.4 ± 0.06 % (w/w) hydroxyapatite was deposited onto the scaffold, and cell viability and DNA content were significantly increased (18.5 ± 0.6 and 33 ± 1.2 %, respectively) compared with the hydroxyapatite scaffold after 14 days. Furthermore, alkaline phosphatase activity in the novel scaffold increased 41 ± 2.5 % after 14 days compared with the hydroxyapatite scaffold. The data indicate that this novel hydroxyapatite/regenerated silk fibroin scaffold has a positive effect on osteoinductivity and osteoconductivity, and may be useful for bone tissue engineering.


Assuntos
Células da Medula Óssea/fisiologia , Durapatita/metabolismo , Fibroínas/metabolismo , Células-Tronco Mesenquimais/fisiologia , Seda/metabolismo , Engenharia Tecidual/métodos , Animais , Células da Medula Óssea/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA/análise , Células-Tronco Mesenquimais/efeitos dos fármacos , Coelhos , Alicerces Teciduais
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