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1.
Adv Healthc Mater ; 12(2): e2201220, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36330558

RESUMO

Hierarchical vasculature reconstruction is fundamental for tissue regeneration. The regeneration of functional vascular network requires a proper directional guidance, especially in case of large-size defects. To provide the "running track" for vasculature, a leaf-vein mimetic membrane using soft and elastic poly(lactide-co-propylene glycol-co-lactide) dimethacrylate is developed. Engraved with an interconnected and perfusable leaf-vein micropattern, the membrane can guide human umbilical vein endothelial cells (HUVECs) to form vasculature in vitro. In particular, the "running track" upregulates the angiogenesis-related gene expression and promotes the HUVECs to differentiate into tip cells and stalk cells via tuning vascular endothelial growth factor receptor 2 signaling transduction. As a proof of concept, its revascularization capability using a rat calvarial defect model in vivo is evaluated. The in vivo results demonstrate that the leaf-vein engraved membrane accelerates the formation and maturation of vasculature, leading to a hierarchical blood vessel network. With the superior pro-vasculature property, it is believed that the leaf-vein engraved membrane is not only an ideal candidate for the reconstruction of calvarial vasculature but also a promising solution for more complicated vasculature reconstruction, such as muscle, skin, and heart.


Assuntos
Materiais Biomiméticos , Células Endoteliais da Veia Umbilical Humana , Neovascularização Fisiológica , Veias , Animais , Humanos , Ratos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Folhas de Planta , Cicatrização , Materiais Biomiméticos/química , Materiais Biomiméticos/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Crânio/metabolismo , Crânio/patologia , Poliésteres/química , Poliésteres/uso terapêutico
2.
Nat Commun ; 13(1): 5189, 2022 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-36057648

RESUMO

Nerve agents, one of the most toxic chemical warfare agents, seriously threaten human life and public security. The high toxicity of nerve agents makes the development of fluorescence sensors with suitable limit of detection challenging. Here, we propose a sensor design based on a conjugated microporous polymer film for the detection of diethyl chlorophosphate, a substitute of Sarin, with low detection limit of 2.5 ppt. This is due to the synergy of the susceptible on-off effect of hybridization and de-hybridization of hybrid local and charge transfer (HLCT) materials and the microporous structure of CMP films facilitating the inward diffusion of DCP vapors, and the extended π-conjugated structure. This strategy provides a new idea for the future development of gas sensors. In addition, a portable sensor is successfully integrated based on TCzP-CMP films that enables wireless, remote, ultrasensitive, and real-time detection of DCP vapors.


Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Humanos , Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/química , Gases , Polímeros/química , Sarina
3.
J Orthop Translat ; 36: 18-32, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35891926

RESUMO

Background: Periosteum is a vascularized tissue membrane covering the bone surface and plays a decisive role in bone reconstruction process after fracture. Various artificial periosteum has been developed to assist the allografts or bionic bone scaffolds in accelerating bone healing. Recently, the biomimicking design of artificial periosteum has attracted increasing attention due to the recapitulation of the natural extracellular microenvironment of the periosteum and has presented unique capacity to modulate the cell fates and ultimately enhance the bone formation and improve neovascularization. Methods: A systematic literature search is performed and relevant findings in biomimicking design of artificial periosteum have been reviewed and cited. Results: We give a systematical overview of current development of biomimicking design of artificial periosteum. We first summarize the universal strategies for designing biomimicking artificial periosteum including biochemical biomimicry and biophysical biomimicry aspects. We then discuss three types of novel versatile biomimicking artificial periosteum including physical-chemical combined artificial periosteum, heterogeneous structured biomimicking periosteum, and healing phase-targeting biomimicking periosteum. Finally, we comment on the potential implications and prospects in the future design of biomimicking artificial periosteum. Conclusion: This review summarizes the preparation strategies of biomimicking artificial periosteum in recent years with a discussion of material selection, animal model adoption, biophysical and biochemical cues to regulate the cell fates as well as three types of latest developed versatile biomimicking artificial periosteum. In future, integration of innervation, osteochondral regeneration, and osteoimmunomodulation, should be taken into consideration when fabricating multifunctional artificial periosteum.The Translational Potential of this Article: This study provides a holistic view on the design strategy and the therapeutic potential of biomimicking artificial periosteum to promote bone healing. It is hoped to open a new avenue of artificial periosteum design with biomimicking considerations and reposition of the current strategy for accelerated bone healing.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(3): 512-519, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34180197

RESUMO

Vision is an important way for human beings to interact with the outside world and obtain information. In order to research human visual behavior under different conditions, this paper uses a Gaussian mixture-hidden Markov model (GMM-HMM) to model the scanpath, and proposes a new model optimization method, time-shifting segmentation (TSS). The TSS method can highlight the characteristics of the time dimension in the scanpath, improve the pattern recognition results, and enhance the stability of the model. In this paper, a linear discriminant analysis (LDA) method is used for multi-dimensional feature pattern recognition to evaluates the rationality and the accuracy of the proposed model. Four sets of comparative trials were carried out for the model evaluation. The first group applied the GMM-HMM to model the scanpath, and the average accuracy of the classification could reach 0.507, which is greater than the opportunity probability of three classification (0.333). The second set of trial applied TSS method, and the mean accuracy of classification was raised to 0.610. The third group combined GMM-HMM with TSS method, and the mean accuracy of classification reached 0.602, which was more stable than the second model. Finally, comparing the model analysis results with the saccade amplitude (SA) characteristics analysis results, the modeling analysis method is much better than the basic information analysis method. Via analyzing the characteristics of three types of tasks, the results show that the free viewing task have higher specificity value and a higher sensitivity to the cued object search task. In summary, the application of GMM-HMM model has a good performance in scanpath pattern recognition, and the introduction of TSS method can enhance the difference of scanpath characteristics. Especially for the recognition of the scanpath of search-type tasks, the model has better advantages. And it also provides a new solution for a single state eye movement sequence.


Assuntos
Algoritmos , Movimentos Oculares , Análise Discriminante , Humanos , Cadeias de Markov , Distribuição Normal , Probabilidade
5.
Anal Chem ; 91(17): 10927-10931, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31305982

RESUMO

Simple and fast detection of chemical warfare agents vapor is necessary and urgent to fight against uncertain terrorist attacks and wars. In this contribution, inspired by the design of the hybrid locally excited and charge transfer (HLCT) excited state, two fast and highly sensitive visualization and fluorescence probes for DCP detection with relative small interstate coupling (J) TPA-2AC and TPA-9AC are reported. Upon exposure to saturated DCP vapor, the TPA-9AC test strips exhibited a rapid fluorescent response in no more than 1 s, accompanied by a change of the color from green to red. The detection limit of the test strips can be estimated as sensitive as 0.15 ppb, which is far superior to the "harmless" level (7 ppb) of human response to acute sarin exposure. More impressively, the fluorescent intensity of the test strips can be quickly restored when exposed to ammonia vapor for cyclic utilization, demonstrating an application prospect in the real-time detection of chemical warfare agents.


Assuntos
Substâncias para a Guerra Química/análise , Corantes Fluorescentes/química , Compostos Organofosforados/análise , Sarina/análise , Espectrometria de Fluorescência/métodos , Reutilização de Equipamento , Humanos , Limite de Detecção , Fitas Reagentes/análise , Eletricidade Estática
6.
Gynecol Obstet Invest ; 80(4): 276-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26160259

RESUMO

Like other stromal-derived gynecological tumors, a sclerosing stromal tumor of the ovary (SSTO) is a rare benign tumor that is difficult to distinguish from a malignant ovarian tumor in clinical practice. An SSTO is routinely treated with laparotomy. Here, we present two extremely rare cases of SSTO with contralateral and ipsilateral tubal pregnancies, in which laparoscopic surgery was performed to remove the tumors. After surgery, one patient (case 1) became pregnant twice within 29 months, and the other patient (case 2) did not become pregnant within 6 months postoperatively. These two cases suggest that laparoscopic management is not only useful in treating SSTO and complicating diseases, but it may also help to reduce unnecessary surgical injury to the ovary.


Assuntos
Neoplasias Ovarianas/cirurgia , Gravidez Tubária/cirurgia , Tumores do Estroma Gonadal e dos Cordões Sexuais/cirurgia , Adulto , Feminino , Humanos , Laparoscopia , Gravidez
7.
Arch Gynecol Obstet ; 288(3): 555-61, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23689738

RESUMO

PURPOSE: Unilateral uterine adnexa absence with a normal uterus is extremely rare but meaningful in clinical. To date, this rare malformation is still not well understood. Here, we present a new case and systematically summarize 38 historical cases to make this rare anomaly be understood better by clinicians. METHOD: The Chinese and English language medical literature were searched for all cases reported to date, and 39 were identified. All 39 cases were assessed for age, menstrual history, reproductive history, pelvic adhesions, other organ abnormalities, and mode of diagnosis. RESULTS: Patient age ranged from 6 days to 46 years. Menstrual history included normal (n = 27), irregular (n = 4), or unknown (n = 7). Childbearing history included pregnancy (n = 21), no history of pregnancy (n = 3), and primary infertility (n = 7). The absence of uterine adnexa involved either the left (n = 17) or right (n = 22) structures, showing a right adnexa preferential bias (22/39). CONCLUSIONS: The unilateral absence of uterine adnexa may be a congenital anomaly of reproductive organs; it does not significantly affect fertility or childbearing and is usually not diagnosed until adulthood.


Assuntos
Anexos Uterinos/anormalidades , Adolescente , Adulto , Criança , Pré-Escolar , Cistadenoma Seroso/diagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Gravidez , Anormalidades Urogenitais/epidemiologia , Adulto Jovem
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