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1.
J Biomater Appl ; 37(8): 1446-1457, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36177498

RESUMO

The mechanism of action underlying the intriguing prominent bioactivity of urinary bladder matrix (UBM) for in situ tissue regeneration of soft tissue defects remains to be elucidated. It is speculated that the activity of UBM for cell adhesion, migration, and activation is inherent. The bioactivity of UBM for in situ tissue regeneration and its relation with the structure and intact soluble components of UBM were investigated in comparison to a collagen-based scaffold, PELNAC (PEL). We isolated the soluble component of the two materials with urea buffer, and evaluated the respective effect of these soluble components on the in vitro adhesion and migration of L929 fibroblasts. The spatiotemporal pattern of endogenous-cell ingrowth into the scaffolds and cell activation were investigated using a model of murine subcutaneous implantation. UBM is more capable of promoting the adhesion, migration, and proliferation of fibroblasts than PEL in a serum-independent manner. In vivo, as compared with PEL, UBM exhibits significantly enhanced activity for fast endogenous cell ingrowth and produces a more prominent pro-regenerative and pro-remodeling microenvironment by inducing the expression of TGF-ß1, VEGF, MMP-9, and murine type I collagen. Overall, our results suggest the prominent bioactivity of UBM for in situ tissue regeneration is inherent.


Assuntos
Matriz Extracelular , Bexiga Urinária , Camundongos , Animais , Bexiga Urinária/química , Matriz Extracelular/metabolismo , Alicerces Teciduais/química , Colágeno Tipo I/metabolismo , Aderências Teciduais/metabolismo , Fibroblastos
2.
Artigo em Inglês | MEDLINE | ID: mdl-35984790

RESUMO

Automatic liver tumor segmentation plays a key role in radiation therapy of hepatocellular carcinoma. In this paper, we propose a novel densely connected U-Net model with criss-cross attention (CC-DenseUNet) to segment liver tumors in computed tomography (CT) images. The dense interconnections in CC-DenseUNet ensure the maximum information flow between encoder layers when extracting intra-slice features of liver tumors. Moreover, the criss-cross attention is used in CC-DenseUNet to efficiently capture only the necessary and meaningful non-local contextual information of CT images containing liver tumors. We evaluated the proposed CC-DenseUNet on the LiTS dataset and the 3DIRCADb dataset. Experimental results show that the proposed method reaches the state-of-the-art performance for liver tumor segmentation. We further experimentally demonstrate the robustness of the proposed method on a clinical dataset comprising 20 CT volumes.

3.
PLoS One ; 17(4): e0265049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35404961

RESUMO

Human dermal fibroblasts (HDFs) play important roles in all stages of wound healing. However, in nonhealing wounds, fibroblasts are prone to aging, resulting in insufficient migration, proliferation and secretion functions. Recent studies have suggested that mesenchymal stromal cells (MSCs) are conducive to wound healing and cell growth through paracrine cytokine signaling. In our studies, we found that conditioned medium of MSCs pretreated with IFN-γ and TNF-α (IT MSC-CM) has abundant growth factors associated with wound repair. Our in vitro results showed that the effects of IT MSC-CM on promoting cell migration, proliferation and activation in HDFs were better than those of conditioned medium from mesenchymal stromal cells (MSC-CM). Moreover, we embedded a scaffold material containing IT MSC-CM and reconfirmed that cell migration and activation were superior to that in the presence of MSC-CM in vivo. Generally, PDGF-BB is perceived as a promoter of the migration and proliferation of HDFs. Moreover, a high level of PDGF-BB in IT MSC-CM was detected, according to which we guess that the effect on HDFs may be mediated by the upregulation of PDGF-BB. These studies all showed the potential of IT MSC-CM to promote rapid and effective wound healing.


Assuntos
Citocinas , Células-Tronco Mesenquimais , Becaplermina/metabolismo , Movimento Celular , Proliferação de Células , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Fibroblastos/metabolismo , Humanos
4.
Pestic Biochem Physiol ; 171: 104744, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357566

RESUMO

The sweetpotato whitefly Bemisia tabaci is a polyphagous crop pest distributed worldwide and frequent exposure to many different defensive secondary metabolites in its host plants. To counteract these defensive plant secondary metabolites, B. tabaci elevate their production of detoxification enzymes, including cytochrome P450 monooxygenases. Besides their tolerance to phytotoxin, B. tabaci have quickly developed resistance to various insecticides in the field. However, the relationship between host plant secondary metabolites and insecticide resistance in B. tabaci is not fully understood. In this study, the influence of plant flavonoid ingestion on B. tabaci tolerance to thiamethoxam and flupyradifurone insecticides and its possible mechanism were examined. Eight plant flavonoids were screened to evaluate their effects on B. tabaci adult sensitivity to thiamethoxam and flupyradifurone. Of which rutin, quercetin, kaempferol, myricetin and catechin significantly reduced adult sensitivity to thiamethoxam and flupyradifurone. Application of cytochrome P450 inhibitor piperonyl butoxide significantly increased the mortality of B. tabaci adults treated with thiamethoxam and flupyradifurone. Moreover, flavonoid ingestion predominantly enhanced the activity of cytochrome P450 enzyme in B. tabaci adults. Meanwhile, the expression level of three cytochrome P450 genes, CYP6CM1, CYP6CX4 and CYP4C64 were induced by the flavonoids in B. tabaci adults. In conclusion, plant flavonoids enhanced the tolerance to thiamethoxam and flupyradifurone in B. tabaci and cytochrome P450s may contribute the flavonoid adaptation. The reduced sensitivity of thiamethoxam and flupyradifurone in flavonoid-fed B. tabaci adults suggested that previous exposure to the host plant-derived flavonoids is likely to compromise the efficacy of insecticides.


Assuntos
Hemípteros , Inseticidas , 4-Butirolactona/análogos & derivados , Animais , Flavonoides/farmacologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Piridinas , Tiametoxam
5.
Plant Methods ; 14: 40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29872452

RESUMO

BACKGROUND: The CRISPR/Cas9 system is being used for genome editing purposes by many research groups in multiple plant species. Traditional sequencing methods to identify homozygous mutants are time-consuming, laborious and expensive. RESULTS: We have developed a method to screen CRISPR/Cas9-induced mutants through Mutation Sites Based Specific Primers Polymerase Chain Reaction (MSBSP-PCR). The MSBSP-PCR method was successfully used to identify homozygous/biallelic mutants in Nicotiana tabacum and Arabidopsis thaliana, and we speculate that it can be used for the identification of CRISPR/Cas9-induced mutants in other plant species. Compared to traditional sequencing methods, MSBSP-PCR is simpler, faster and cheaper. CONCLUSIONS: The MSBSP-PCR method is simple to implement and can save time and cost in the screening of CRISPR/Cas9-induced homozygous/biallelic mutants.

6.
Plant Physiol ; 173(2): 1391-1408, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27913741

RESUMO

The mitogen-activated protein kinase (MAPK) cascade is an evolutionarily conserved signal transduction module involved in transducing extracellular signals to the nucleus for appropriate cellular adjustment. This cascade essentially consists of three components: a MAPK kinase kinase (MAPKKK), a MAPK kinase, and a MAPK, connected to each other by the event of phosphorylation. Here, we report the characterization of a MAPKKK, ABA-INSENSITIVE PROTEIN KINASE1 (AIK1), which regulates abscisic acid (ABA) responses in Arabidopsis (Arabidopsis thaliana). T-DNA insertion mutants of AIK1 showed insensitivity to ABA in terms of both root growth and stomatal response. AIK1 functions in ABA responses via regulation of root cell division and elongation, as well as stomatal responses. The activity of AIK1 is induced by ABA in Arabidopsis and tobacco (Nicotiana benthamiana), and the Arabidopsis protein phosphatase type 2C, ABI1, a negative regulator of ABA signaling, restricts AIK1 activity by dephosphorylation. Bimolecular fluorescence complementation analysis showed that MPK3, MPK6, and AIK1 interact with MKK5. The single mutant seedlings of mpk6 and mkk5 have similar phenotypes to aik1, but mkk4 does not. AIK1 was localized in the cytoplasm and shown to activate MKK5 by protein phosphorylation, which was an ABA-activated process. Constitutively active MKK5 in aik1 mutant seedlings complements the ABA-insensitive root growth phenotype of aik1 The activity of MPK6 was increased by ABA in wild-type seedlings, but its activation by ABA was impaired in aik1 and aik1 mkk5 mutants. These findings clearly suggest that the AIK1-MKK5-MPK6 cascade functions in the ABA regulation of primary root growth and stomatal response.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/genética , Estômatos de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/genética
7.
Chin Med J (Engl) ; 129(8): 946-52, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27064040

RESUMO

BACKGROUND: The prevalence of sudden sensorineural hearing loss in children (CSSNHL) is consistently increasing. However, the pathology and prognosis of CSSNHL are still poorly understood. This retrospective study evaluated clinical characteristics and possible associated factors of CSSNHL. METHODS: One hundred and thirty-six CSSNHL patients treated in Department of Otolaryngology-Head and Neck Surgery and Institute of Otolaryngology at Chinese PLA General Hospital between July 2008 and August 2015 were included in this study. These patients were analyzed for clinical characteristics, audiological characteristics, laboratory examinations, and prognostic factors. RESULTS: Among the 136 patients (151 ears), 121 patients (121 ears, 80.1%) were diagnosed with unilaterally CSSNHL, and 15 patients (30 ears, 19.9%) with bilateral CSSNHL. The complete recovery rate of CSSNHL was 9.3%, and the overall recovery rate was 37.7%. We found that initial degree of hearing loss, onset of treatment, tinnitus, the ascending type audiogram, gender, side of hearing loss, the recorded auditory brainstem response (ABR), and distortion product otoacoustic emissions (DPOAEs) had prognostic significance. Age, ear fullness, and vertigo had no significant correlation with recovery. Furthermore, the relevant blood tests showed 30.8% of the children had abnormal white blood cell (WBC) counts, 22.1% had elevated homocysteine levels, 65.8% had high alkaline phosphatase (ALP), 33.8% had high IgE antibody levels, and 86.1% had positive cytomegalovirus (CMV) IgG antibodies. CONCLUSIONS: CSSNHL commonly occurs unilaterally and results in severe hearing loss. Initial severe hearing loss and bilateral hearing loss are negative prognostic factors for hearing recovery, while positive prognostic factors include tinnitus, gender, the ascending type audiogram, early treatment, identifiable ABR waves, and DPOAEs. Age, vertigo, and ear fullness are not correlated with the recovery. Some serologic indicators, including the level of WBC, platelet, homocysteine, ALP, positive CMV IgG antibody, fibrinogen, and some immunologic indicators, are closely related to CSSNHL.


Assuntos
Perda Auditiva Neurossensorial/etiologia , Adolescente , Criança , Pré-Escolar , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Perda Auditiva Neurossensorial/sangue , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Emissões Otoacústicas Espontâneas , Estudos Retrospectivos
8.
Artigo em Chinês | MEDLINE | ID: mdl-26911052

RESUMO

OBJECTIVE: The aim of this retrospective study was to analyze the recovery rate of sudden sensorineural hearing loss in children, and explore the prognostic factors in order to guide the clinical diagnosis and treatment. METHOD: A retrospective review was conducted for the prognosis of children with sudden sensorineural hearing loss during the past 5 years (from November 2010 to May 2015) in Chinese PLA General Hospital. This paper have a complete clinical data of 101 patients (113 ears)with sudden hearing loss, ranging from 0 to 18 years old Patients were divided into four groups according to hearing recovery and eight putative prognostic factors were analyzed. RESULT: Among 101 patients (113 ears), the ratio of male and female was 60:53. Treatment was initiated from 1 to 183 days after disease onset, with an average of (18.5 ± 22.1) d. Bilateral and unilateral hearing loss were 24 ears and 89 ears, respectively. The proportion of mild hearing loss, moderate hearing loss, severe hearing loss and profound hearing loss were 7.1%, 6.2%, 23.9% and 62.8%, respectively. Vertigo and tinnitus occurred in 54.9% and 77.9% of the patients, respectively. After the treatment, the complete recovery rate was 9.7% and the overall recovery rate was 36.3%. The degree of hearing loss, earlier treatment onset, sex and bilateral involvement were significantly associated with hearing recovery (P < 0.05). CONCLUSION: Sudden sensorineural hearing loss in children was generally identified as severe and profound hearing loss, but after positive and timely treatment, it can be improved or even cured. The mild hearing loss, earlier treatment onset, unilateral hearing loss and female were positive prognostic factors. The concurrence of tinnitus or vertigo, the results of ABR and DPOAE had no significant influence on prognosis.


Assuntos
Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Súbita/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Perda Auditiva Unilateral/diagnóstico , Testes Auditivos , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Estudos Retrospectivos , Zumbido/complicações , Vertigem/complicações
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