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1.
Langmuir ; 40(22): 11401-11410, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38767862

RESUMO

To functionalize interfaces with supported biomembranes and membrane proteins, the challenge is to build stabilized and supported systems that mimic the native lipid microenvironment. Our objective is to control substrate-to-biomembrane spacing and the tethering chemistry so proteoliposomes can be fused and conjugated without perturbation of membrane protein function. Furthermore, the substrates need to exhibit low protein and antibody nonspecific binding to use these systems in assays. We have employed protein orthogonal coupling schemes in concert with multiarm poly(ethylene glycol) (PEG) technology to build supported biomembranes on microspheres. The lipid bilayer structures and tailored substrates of the microsphere-supported biomembranes were analyzed via flow cytometry, confocal fluorescence, and super-resolution imaging microscopy, and the lateral fluidity was quantified using fluorescence recovery after photobleaching (FRAP) techniques. Under these conditions, the 4-arm-PEG20,000-NH2 based configuration gave the most desirable tethering system based on lateral diffusivity and coverage.


Assuntos
Bicamadas Lipídicas , Polietilenoglicóis , Polietilenoglicóis/química , Bicamadas Lipídicas/química , Microesferas , Recuperação de Fluorescência Após Fotodegradação , Polímeros/química
2.
BMC Infect Dis ; 23(1): 70, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747151

RESUMO

BACKGROUND: Serum lipids variations are closely related to the sepsis progression; however, their value for patients with pyogenic liver abscesses (PLA) has rarely been studied. We investigated the serum lipid level variations in patients with PLA and its predictive value to the disease. METHODS: The study included 328 patients with PLA hospitalized in the First Affiliated Hospital of Nanjing Medical University from January 2017 to December 2021; 35 (10.67%) in the severe group (SG) and 293 (89.33%) in the non-severe group (nSG). Their clinical records were analyzed retrospectively, and dynamic curves were drawn to clarify the changes in different indicators during the course of the disease. RESULTS: High-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and lipoprotein(a) (Lp(a)) in the SG were significantly lower than those in nSG (P < 0.001). Total cholesterol (TC) at baseline (OR = 0.184, P < 0.001) was an independent risk factor for severe patients and had the highest predictive value, with an area under the curve of 0.859 and a cut-off value of 2.70 mmol/L (sensitivity = 94.3%, specificity = 63.5%). For patients who met the criteria for drainage surgery, TC, HDL-C and LDL-C levels continued to decrease with antibiotic therapy alone before drainage and began to increase after the surgery. CONCLUSIONS: Low TC level on admission is an independent risk factor for the progression of severe illness in PLA patients, with the highest predictive value surpassing other routine clinical indices. Abscess drainage should be performed as soon as possible for patients whose TC continues to decline after medical treatment.


Assuntos
Colesterol , Abscesso Hepático Piogênico , Humanos , Estudos Retrospectivos , LDL-Colesterol , Triglicerídeos , Prognóstico , Relevância Clínica , HDL-Colesterol , Poliésteres
3.
Acta Orthop Belg ; 84(1): 108-115, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30457509

RESUMO

To evaluate and compare the clinical and radiographic results between temporary C1-C2 pedicle screw fixation and cable-dragged reduction and cantilever beam internal fixation. Between 2010 and 2013, temporary C1-C2 pedicle screw fixation (Group P, 28 patients) and cable-dragged reduction following cantilever beam internal fixation (Group C, 33 patients) were performed on type II odontoid fracture cases. Implants were removed after fracture union. All of the 61 surgeries were performed successfully with no iatrogenic neurological worsen. One patient in Group P detected intra-operative vertebral artery injury. All patients gained fracture union. Among the observed indexes, only blood loss in Group P (128.9 ± 73.9ml) is statistically higher than in Group C (97.3 ± 5 4.2ml). Pedicle screw fixation carries the risk of vertebral artery injury, especially in patients with high-riding vertebral artery. Cable-dragged reduction following cantilever beam internal fixation could avoid the potential risk of vertebral injury, but it prolonged the fixed segments. We thought cable-dragged reduction following cantilever beam internal fixation could be an alternative method for treating type II odontoid fracture.


Assuntos
Fixação Interna de Fraturas/métodos , Processo Odontoide/lesões , Fraturas da Coluna Vertebral/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processo Odontoide/cirurgia , Parafusos Pediculares , Resultado do Tratamento
4.
Oecologia ; 180(3): 771-83, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26563469

RESUMO

In forest succession, the ecological strategies of the dominant species that are based on functional traits are important in the determination of both the mechanisms and the potential directions of succession. Thirty-one plots were established in the Loess Plateau region of northern Shaanxi in China. Fifteen leaf traits were measured for the 31 dominant species that represented the six stages of succession, and the traits included four that were related to morphology, seven to stoichiometry and four to physiological ecology. The species from the different successional stages had different patterns of distribution of the traits, and different key traits predicted the turnover of the species during succession. The ash and the cellulose contents were key regulatory factors of species turnover in the early successional communities, and the trait niche forces in sugar and leaf dry mass content might become more important with the progression of succession. When only the three herb stages were considered, a progressive replacement of the ruderal by the competitive-ruderal species occurred in the intermediate stages of succession, which was followed by the stress-tolerant-competitive or the competitive-stress tolerant-ruderal strategists late in the succession. Thus, the different species that occurred in the different stages of succession shared different trait-based ecological strategies. Additionally, these differences occurred concomitantly with a shift toward competitive-stress tolerant-ruderal strategies.


Assuntos
Adaptação Fisiológica , Metabolismo dos Carboidratos , Ecologia , Florestas , Fenótipo , Folhas de Planta , Plantas , Carboidratos , Celulose , China , Fenômenos Fisiológicos Vegetais , Plantas/metabolismo , Árvores/metabolismo , Árvores/fisiologia
5.
Drug Dev Ind Pharm ; 40(3): 301-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23350690

RESUMO

In this study, cinnamic acid-loaded transfersomes were prepared and dermal microdialysis sampling was used in Sprague-Dawley rats to compare the amount of drug released into the skin using transfersomes as transdermal carriers with that released on using conventional liposomes. The formulation of cinnamic acid-loaded transfersomes was optimized by a uniform design through in vitro transdermal permeation studies. Hydration time was confirmed as a significant factor influencing the entrapment efficiency of transfersomes, further affecting their transdermal flux in vitro. The fluxes of cinnamic acid from transfersomes were all higher than those from conventional liposomes, and the flux from the optimal transfersome formulation was 3.01-fold higher than that from the conventional liposomes (p < 0.05). An in vivo microdialysis sampling method revealed that the dermal drug concentrations from transfersomes applied on various skin regions were much lower than those required with conventional liposomes. After the administration of drug-containing transfersomes and liposomes on abdominal skin regions of rats for a period of 10 h, the Cmax of cinnamic acid from the compared liposomes was 3.21 ± 0.25 µg/mL and that from the transfersomes was merely 0.59 ± 0.02 µg/mL. The results suggest that transfersomes can be used as carriers to enhance the transdermal delivery of cinnamic acid, and that these vehicles may penetrate the skin in the complete form, given their significant deformability.


Assuntos
Cinamatos/administração & dosagem , Sistemas de Liberação de Medicamentos , Microdiálise/métodos , Absorção Cutânea , Administração Cutânea , Animais , Química Farmacêutica , Cinamatos/farmacocinética , Lipossomos , Masculino , Ratos , Ratos Sprague-Dawley
6.
Zookeys ; 1196: 271-283, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586078

RESUMO

A new species of pomatiopsid freshwater snail, Fenouiliaundata Chen & He, sp. nov., is described from Guangxi, China, based on morphological and molecular evidence. The new species can be distinguished from its congeners by the following combination of characters: shell with low, prosocline, rounded axial ribs and fine spiral striae, broader than high; aperture broader than shell height; radula with lateral teeth have only two or three faint, wavy ridges on inner side. A molecular analysis of partial mitochondrial COI and 16S DNA sequences supports the systematic position of the new taxon.

7.
Orthop Surg ; 15(1): 152-161, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36398388

RESUMO

OBJECTIVE: The nanohydroxyapatite/polyamide-66 (n-HA/PA66) cage is a novel bioactive nonmetal cage that is now used in some medical centers, while the polyetheretherketone (PEEK) cage is a typical device that has been widely used for decades with excellent clinical outcomes. This study was performed to compare the long-term radiographic and clinical outcomes of these two different cages used in transforaminal lumbar interbody fusion (TLIF). METHODS: In this retrospective and matched-pair case control study, we included 200 patients who underwent TLIF from January 2010 to December 2014 with a minimum 7-year follow-up. One hundred patients who used n-HA/PA66 cages were matched with 100 patients who used PEEK cages for age, sex, diagnosis, and fusion level. The independent student's t-test and Pearson's chi-square test were used to compare the two groups regarding radiographic (fusion status, cage subsidence rate, segmental angle [SA], and interbody space height [IH]) and clinical (Oswestry Disability Index [ODI], and Visual Analog Scale [VAS] for back and leg) parameters preoperatively, postoperatively, and at the final follow-up. RESULTS: The n-HA/PA66 and PEEK groups had similar fusion rates of bone inside and outside the cage at the final follow-up (95.3% vs 91.8%, p = 0.181, 92.4% vs 90.1%, p = 0.435). The cage union ratios exposed to the upper and lower endplates of the n-HA/PA66 group were significantly larger than those of the PEEK group (p < 0.05). The respective cage subsidence rates in the n-HA/PA66 and PEEK groups were 10.5% and 17.5% (p = 0.059). There were no significant differences between the two groups in the SA, IH, ODI scores, or VAS scores at any time point. The n-HA/PA66 group showed high fusion and low subsidence rates during long-term follow-up. CONCLUSION: Both n-HA/PA66 and PEEK cages can achieve satisfactory long-term clinical and radiographic outcomes in TLIF. However, the n-HA/PA66 group showed significantly larger cage union ratios than the PEEK group. Therefore, the results indicated that the n-HA/PA66 cage is an ideal alternative material comparable to the PEEK cage in TLIF.


Assuntos
Nylons , Fusão Vertebral , Humanos , Estudos de Casos e Controles , Estudos Retrospectivos , Resultado do Tratamento , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Polietilenoglicóis/uso terapêutico , Cetonas/uso terapêutico
8.
Zhonghua Wai Ke Za Zhi ; 50(4): 338-41, 2012 Apr.
Artigo em Zh | MEDLINE | ID: mdl-22800787

RESUMO

OBJECTIVE: To initially evaluate the application of artificial vertebra of n-HA/PA66 in anterior reconstruction of lower cervical spine fracture and dislocation. METHODS: In this study, 84 patients with lower cervical spine fracture and dislocation received anterior cervical discectomy, spinal canal decompression or subtotal corpectomy, spinal canal decompression and reconstruction by n-HA/PA66 composite artificial vertebral body combined with plate instrumentation. Neurological function was followed up by improvement rate of Frankel and situations of the supporting body was observed by X ray and 3D-CT in 3, 12, 24 months postoperatively. The intervertebral height, physical arc (reflected by Cobb angle) and the locations and fusion rate of the supporting body were assessed in order to evaluate the stability of the cervical spine and alignment improvements. RESULTS: All the patients underwent operation successfully and were followed up for 6 to 24 months with an average of 12 months. The preoperative symptoms were improved to varying degrees. Imaging studies showed that in all cases graft fusion were achieved, and cervical alignments, intervertebral height, cervical spine stability and the locations of the artificial vertebral body were well maintained. No displacement and subsidence of the artificial vertebral body occurred. Postoperative immediate intervertebral height (2.4 ± 0.2) cm, preoperative intervertebral height (1.9 ± 0.1) cm, comparisons of the two groups was statistically significant (q = 2.48, P < 0.001). The immediate, 3 month, 1 year, 2 year period follow-up group intervertebral height was not statistically significant (P > 0.05). Preoperative Cobb angle was 9.8° ± 1.2°, postoperative immediate Cobb angle was 16.6° ± 1.2°, comparisons of the two groups was statistically significant (q = 14.25, P < 0.001). The immediate, 3 month, 1 year, 2 year period follow-up group Cobb angle was not statistically significant (P > 0.05). CONCLUSIONS: n-HA/PA66 artificial vertebral body can provide early cervical spine support and stability and effectively maintain the biological alignment and cervical intervertebral height. It has high rate of graft fusion and is convenient to observe by X-ray. Therefore, n-HA/PA66 can be taken as an ideal graft for anterior lower cervical spine fracture and dislocation operation, but further follow-up study is still required to evaluate the long-term effects.


Assuntos
Substitutos Ósseos , Vértebras Cervicais/lesões , Nanoestruturas , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/instrumentação , Adolescente , Adulto , Idoso , Vértebras Cervicais/cirurgia , Descompressão Cirúrgica , Feminino , Seguimentos , Fixação Interna de Fraturas , Humanos , Hidroxiapatitas , Luxações Articulares/complicações , Luxações Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Nylons , Fraturas da Coluna Vertebral/complicações , Adulto Jovem
9.
IEEE J Biomed Health Inform ; 26(5): 2320-2330, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34910643

RESUMO

Saliva contains similar molecular components to serum. Analysis of saliva can provide important diagnostic information about the body. Here we report an artificial intelligence (AI) aided home-based method that can let pregnant women perform daily monitoring on their pregnant status and accurate prediction on their delivery date by the pattern analysis of their salivary crystals. The method was developed based on the information obtained from our investigation on the saliva samples of 170 pregnant women about the correlation of the salivary crystal pattern with pregnant age and fetal status. It demonstrated that the patterns of salivary crystallization could act as indicators of the pregnant age, fetal state, and some medical conditions of pregnant women. On this basis, with the aid of AI recognition and analysis of the fractal dimension and some characteristic crystals in the salivary crystallization, we performed estimation on the delivery date in both quantitative and qualitative manners. The accuracy of the prediction on 15 pregnant women was satisfactory: 100% delivering in the predicted week, 93.3% within the estimated three days, and 86.7% on the day as the prediction. We also developed a simple smartphone-based AI-aided salivary crystal imaging and analysis device as an auxiliary means to let pregnant women monitor their fetal status daily at home and predict their delivery date with adequate accuracy.


Assuntos
Gestantes , Saliva , Inteligência Artificial , Cristalização , Feminino , Feto , Humanos , Gravidez , Saliva/química
10.
Nanomedicine (Lond) ; 17(30): 2215-2229, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36927097

RESUMO

Aim: To explore how to transform cocrystals of the anticancer drug 5-fluorouracil (FL) with caffeic acid (CF; FL-CF-2H2O) into a nanoformulation, a self-assembly strategy of cocrystal-loaded micelles is proposed. Methods: Nanomicelles were assembled to deliver cocrystal FL-CF-2H2O with synergistic activity, and their in vitro/vivo properties were evaluated by combining theoretical and experimental methods. Result: More cocrystal was packed into the polymers due to the stronger interaction energy during micellar assembly, producing excellent cytotoxicity and pharmacokinetic behavior, especially synergistic abilities and long-term therapy. Conclusion: This case exemplifies the particular benefits of the self-assembly strategy of cocrystal-loaded micelles in keeping a delicate balance between long-term effects and high efficiency for FL, and offers a feasible technical scheme for cocrystal delivery agents for antitumor drugs.


To exemplify the feasibility of the cocrystal conversion of anticancer drug 5-fluorouracil (FL) with phenolic acid nutrient caffeic acid (CF) into a nanomicelle formulation, and further provide new options for the development of slowed-release cocrystal formulations with long-acting and synergistic antitumor effects, in this study, a cocrystalline complex of FL and CF (cocrystal FL-CF-2H2O) was loaded into polymer PEG-PCL to successfully assemble the cocrystal nanomicelles by a self-assembly strategy. The morphology of the cocrystal nanomicelles was characterized, and in vitro/vivo properties were evaluated by combining theoretical with experimental methods. The results showed that the cocrystal nanomicelles with regular sphericity and homogeneous particle size had greater drug loading and entrapment efficiency than FL nanomicelles, which is also supported by theoretical predictions of the interaction energy between the cocrystal FL-CF-2H2O and polymer PEG-PCL. The excellent encapsulation effects give rise to more potent cytotoxicity, better absorption and prolonged retention time in vivo. Relative to FL nanomicelles, the present cocrystal nanomicelles with synergistic antitumor abilities exhibited prominent slowed-release behavior that was more conducive to the long-term maintenance of therapeutic concentrations in vivo. The present case offers a feasible technical scheme for successful nanoformulation research on synergistic antitumor pharmaceutical cocrystals.


Assuntos
Antineoplásicos , Micelas , Fluoruracila/farmacologia , Polímeros/química , Antineoplásicos/farmacologia , Portadores de Fármacos
11.
Eur Spine J ; 20(12): 2240-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21544594

RESUMO

Biodegradable copolymer α-TCP/poly(amino acid) composite artificial lamina was prepared and used in goat cervical vertebra resection repair. Cervical 4 was removed by laminectomy, and a vertebra defect of 27 × 9 mm was made. α-TCP/poly(amino acid) composite artificial lamina was inserted in the test group. The efficiency of the copolymer during repair and reconstruction of the goats' vertebra was tested by using X-ray, CT scanning, and histological and biomechanical measurements. In the 24 weeks following the operation, the artificial lamina refrained from shifting, and no dural adhesion pressure was observed. In contrast, the control group suffered from infiltration of soft tissue in the spinal canal, dural pressure and α-TCP/poly(amino acid) degradation. In conclusion, α-TCP/poly(amino acid) composite artificial lamina can significantly prevent scar tissue from infiltrating the spinal canal.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis , Vértebras Cervicais/cirurgia , Cicatriz/prevenção & controle , Doenças da Coluna Vertebral/prevenção & controle , Animais , Cabras , Polímeros , Aderências Teciduais/prevenção & controle , Cicatrização
12.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(4): 454-459, 2020 Aug 01.
Artigo em Zh | MEDLINE | ID: mdl-32865368

RESUMO

Severe congenital neutropenia is a rare disorder characterized by a consistently low absolute neutrophil count and periodontal disease. This report describes the case of an ELANE mutationin a patient with gingival bleeding and tooth mobility. Oral examination showed active periodontal infection of the primary dentition accompanied by alveolar bone loss in the posterior region. The patient was diagnosed with severe congenital neutropenia 1 year after multidisciplinary consultation. Treatment of the systemic disease and effective oral health education over a 3-year follow-up period relieved the periodontal infection and created favorable conditions for future repair.


Assuntos
Síndrome Congênita de Insuficiência da Medula Óssea , Neutropenia , Doenças Periodontais , Humanos , Mutação , Neutropenia/congênito
13.
Gene ; 665: 35-40, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29705123

RESUMO

AIM: To explore the association of CCL3 (rs1063340) and CCL4 (rs1049807) polymorphisms with hepatitis C virus (HCV) clearance and sustained virologic response (SVR). METHODS: Two populations were enrolled in the current study; one was a general population including 1585 untreated individuals, with HCV infection and the other was a treatment population comprising 353 HCV-infected patients treated with pegylated interferon-α and ribavirin (pegIFN-α/RBV). Two single nucleotide polymorphisms (SNPs) were genotyped, and the relationship between HCV clearance and treatment outcome was analysed. RESULTS: The general population comprised 995 persistent HCV cases (both HCV RNA and anti-HCV were positive) and 590 spontaneous clearance cases (HCV RNA was negative, but anti-HCV was positive). An association between the SNPs and HCV clearance was not found in our study. The treatment population consisted of 235 patients who achieved SVR and 118 non-responders. Variants of both SNPs (rs1063340-C and rs1049807-G) were associated with a reduction in SVR following IFN treatment (dominant model: P = 0.026 for rs1063340 and P = 0.048 for rs1049807). In addition, the ancestral alleles of rs1063340 and rs1049807 increased the likelihood of virus clearance by 62% compared to both the derived and minor alleles of the two SNPs (P = 0.040).The interaction analysis showed that the level of glucose interacted with the association of rs1063340 and SVR. CONCLUSIONS: Our results suggested that genetic variants at the CCL3 and CCL4 loci may be marker SNPs for risk of HCV treatment outcome.


Assuntos
Quimiocina CCL3/genética , Quimiocina CCL4/genética , Hepatite C/genética , Polimorfismo de Nucleotídeo Único , Adulto , Povo Asiático/etnologia , Povo Asiático/genética , China/etnologia , Feminino , Hepatite C/tratamento farmacológico , Hepatite C/etnologia , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Ribavirina/administração & dosagem
14.
BMJ Open ; 8(4): e019406, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29654010

RESUMO

OBJECTIVE: The human leucocyte antigen-DO (HLA-DO) gene located in the HLA non-classical class-II region may play a role in treatment response to hepatitis C virus (HCV). This study was conducted to explore the role of single nucleotide polymorphisms (SNPs) in HLA-DO in responding to HCV therapy. SETTING: All patients were recruited between January 2011 and September 2016 from the Jurong People's Hospital, Jiangsu Province, China. PARTICIPANTS: A total of 346 chronic hepatitis C (CHC) patients who finished the 48-week pegylated interferon-alpha and ribavirin (PEG IFN-α/RBV) treatment were enrolled in this study. All patients were former remunerated blood donors. The inclusion criteria for patients were as follows: (1) treatment-naive and treated with PEG IFN-α/RBV, (2) HCV RNA was present in serum for over 6 months before treatment, (3) negative for hepatitis B (HBV) or HIV infection and (4) lacked any other hepatic diseases.All participants in this study were Chinese Han population and infected with HCV genotype 1b and treated with subcutaneous PEG IFN-α at a dose of 180 µg once a week with the addition of 800-1000 mg/d RBV according to weight orally for 48 weeks. RESULTS: The SNPs HLA-DOA rs1044429 and HLA-DOB rs2284191 and rs2856997 of 18 SNPs were correlated with HCV treatment response in the Chinese Han population. The dominant model indicated that patients carrying favourable genotypes at rs1044429 AA and rs2284191 AA were more likely to achieve sustained virological response (SVR) (OR 1.99, 95% CI 1.25 to 3.19; OR 2.71, 95% CI 1.58 to 4.63, respectively), while patients carrying unfavourable genotypes at rs2856997 GG were less likely to achieve SVR (OR 0.48, 95% CI 0.29 to 0.78). CONCLUSION: Genetic variations at rs1044429, rs2284191 and rs2856997 were independent predictors of HCV treatment response in the Chinese Han population.


Assuntos
Antivirais/uso terapêutico , Antígenos HLA-D/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Ribavirina/uso terapêutico , China , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
15.
Cell Rep ; 23(7): 2083-2094.e6, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29768206

RESUMO

The effector B cell lymphoma-2 (BCL-2) protein BCL-2 ovarian killer (BOK) induces mitochondrial outer membrane permeabilization (MOMP) to initiate apoptosis upon inhibition of the proteasome. How BOK mediates MOMP is mechanistically unknown. The NMR structure of the BCL-2 core of human BOK reveals a conserved architecture with an atypical hydrophobic groove that undergoes conformational exchange. Remarkably, the BCL-2 core of BOK spontaneously associates with purified mitochondria to release cytochrome c in MOMP assays. Alanine substitution of a unique glycine in helix α1 stabilizes BOK, as shown by thermal shift and urea denaturation analyses, and significantly inhibits MOMP, liposome permeabilization, and cell death. Activated BID does not activate WT BOK or the stabilized alanine mutant to promote cell death. We propose that BOK-mediated membrane permeabilization is governed in part by its unique metastability of the hydrophobic groove and helix α1 and not through activation by BH3 ligands.


Assuntos
Apoptose , Permeabilidade da Membrana Celular , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Glicina/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ativação do Canal Iônico , Ligantes , Lipossomos , Espectroscopia de Ressonância Magnética , Camundongos Endogâmicos C57BL , Membranas Mitocondriais/metabolismo , Mutagênese , Conformação Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteínas Proto-Oncogênicas c-bcl-2/química , Homologia Estrutural de Proteína
16.
World J Gastroenterol ; 13(20): 2798-802, 2007 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-17569114

RESUMO

AIM: To evaluate the effect of hydroxyapatite nano-particles (Nano HAP) by intravenous injection on the inhibition of implanted hepatic VX(2) tumor growth in rabbits and cell p53/c-Myc protein expression. METHODS: 60 hepatic VX(2) tumor-bearing rabbits was randomly divided into five groups. Nano HAP collosol 20 mg/kg, 40 mg/kg, 5-FU solutions 20 mg/mL, mixed liquor of 5-FU solution 20 mg/mL and Nano HAP collosol 20 mg/kg were infused by vein, normal saline conducted as the control. The general state, weight, liver function and gross tumor volume were detected dynamically. The expression of p53 and c-Myc gene protein in tumor tissue was detected by immunohistochemistry methods. RESULTS: The growth of implanted hepatic VX(2) tumors was significantly inhibited in all therapy groups, 3 wk after the injection, the tumor control rates in Nano HAP collosol groups were 25.5% and 32.5% respectively, and the gross tumor volumes were obviously less than that of control group. (24.81 +/- 5.17 and 22.73 +/- 4.23 vs 33.32 +/- 5.26, P<0.05). The tumor control rate of 5-FU group was 43.7% (18.74 +/- 4.40 vs 33.32 +/- 5.26, P<0.05), but the general state of the animals after injection aggravated; and the adverse reaction in the drug combination group obviously decreased. Due to the effect of Nano HAP, the positive expression of tumor associated the mutated p53 and c-Myc in tumor tissue was decreased obviously compared with the control group. CONCLUSION: Nano HAP has evident inhibitory action on rabbit implanted hepatic VX(2) tumor in vivo, which may be the result of decreasing the expression of the mutated p53 and c-myc, and drug combination can obviously decrease the adverse reaction of 5-FU.


Assuntos
Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Durapatita/farmacologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Materiais Biocompatíveis/administração & dosagem , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Quimioterapia Combinada , Durapatita/administração & dosagem , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Injeções Intravenosas , Fígado/patologia , Fígado/fisiopatologia , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Nanopartículas/administração & dosagem , Coelhos , Distribuição Aleatória , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética
17.
PLoS One ; 12(6): e0179668, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28640855

RESUMO

OBJECTIVE: This study was conducted to investigate the effect of subpressure on the bond strength of resin to zirconia ceramic. The subpressure would create a pressure gradient which could clean out the bubbles in the adhesives or bonding interface. METHODS: Twenty-eight pre-sintered zirconia discs were fabricated. Half of them were polished (group P, n = 14), and the rest were sandblasted (group S, n = 14). After sintered,the surface roughness of the zirconia discs was measured. Then, they were randomly divided into two subgroups (n = 7). The groups were named as follows: PC: P + no additional treatments; PP: P + 0.04 MPa after application of adhesives; SC: S + no additional treatments; and SP: S + 0.04 MPa after application of adhesives. Resin columns were bonded to the zirconia specimens to determine shear bond strength (SBS). The bonding interfaces were observed and the fracture modes were evaluated. Statistical analysis was performed on all data. RESULTS: The surface roughness of group S was significantly higher than that of group P (P<0.05). The SBS values were PC = 13.48 ± 0.7 MPa, PP = 15.22 ± 0.8 MPa, SC = 17.23 ± 0.7 MPa and SP = 21.68 ± 1.4 MPa. There were significant differences among the groups (P<0.05). Scanning electron microscopy (SEM) results showed that the adhesives of group SP and PP were closer and denser to the zirconia ceramic than that of group PC and SC. The proportion of the mixed fracture mode significantly increased after adding subpressure (P< 0.05). CONCLUSION: Subpressure can improve the shear bond strength of resin to zirconia ceramics and increase micro-infiltration between the adhesives and the zirconia ceramics, especially on the rough surfaces.


Assuntos
Cerâmica/química , Pressão , Cimentos de Resina/química , Zircônio/química , Resistência ao Cisalhamento , Propriedades de Superfície
18.
Sci Rep ; 7(1): 6831, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28754954

RESUMO

This study aimed to investigate the effects of subpressure on the bond properties of total-etching adhesive to dentin. Thirty-six caries-free premolars were sectioned parallel to the occlusal plane and randomly divided into four groups (n = 9): a control group (C, no treatment) and three subpressure groups, which were treated under 0.8, 0.6 or 0.4 bar after applying adhesives, named S8, S6 and S4, respectively. Afterward, resin was bonded to the dentin surface, and 27 beams (1.0 mm × 1.0 mm) of each group were sectioned. One was selected to observe the bonding interface from each group by SEM. Each group was divided into two subgroups (n = 13): 24 hours of water storage (I) and 10,000 thermocycling (A). The microtensile bond strength (µTBS), failure modes and nanoleakage expression were evaluated. SEM results showed that the subpressure groups had longer and denser resin tags. The µTBS of the subpressure groups was higher than that of the control group (p < 0.05). The subpressure groups were dominated by mixed failure, whereas main interfacial failure appeared in group C. The subpressure groups showed less silver deposition than the control group (p < 0.05). The subpressure technique may remarkably improve bonding strength and decrease nanoleakage on total-etching bonding.


Assuntos
Colagem Dentária/métodos , Dente Pré-Molar/efeitos dos fármacos , Dente Pré-Molar/ultraestrutura , Colagem Dentária/instrumentação , Dentina/efeitos dos fármacos , Dentina/ultraestrutura , Humanos , Pressão , Cimentos de Resina/farmacologia
19.
Chin J Traumatol ; 9(3): 146-51, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16723072

RESUMO

OBJECTIVE: To determine the efficacy of polylactic acid glue in preventing epidural scar adhesion after laminectomy in rabbits. METHODS: Twenty-four Japanese white rabbits underwent laminectomy (including the attached ligaments) at L(2 ) and L(5). After laminectomy at L(5), polylactic acid glue was sprayed on the dura and nerve roots and this segment was taken as the experimental group. After laminectomy at L(2), nothing was used and this segment was enrolled as the self control group. Four rabbits were killed every two weeks postoperatively till the end of the experiment at 12 weeks. Then the operated spine was observed grossly, histologically and ultrastructurally to check the degree of scar formation, the status of epidural scar adhesion, the absorption of the glue, and the intracellular structure of fibroblasts. RESULTS: The glue coagulated immediately after spraying and showed excellent hemostatic effect. The glue membrane was easy to be taken away from the dura mater of the samples for 2 weeks and there were no cells in the epidural space in the experimental group. But the dura mater was covered by hematoma in the control group, which formed mild adhesion, with fibroblasts proliferating actively. In the 4th week, some glue shivers remained in the epidural space with fibroblasts increasing a little, and the dura mater was smooth in the experimental group. However, in the control group, the formed scar was fragile and conglutinated with the dura mater diffusely and fibroblasts were much more than those in the experimental group. In the 6th-12th weeks, there was a potential interspace between the scar and the dura mater, and the polylactic acid glue was absorbed completely in the experimental group. Much tough scar was found in the control group, which was very difficult to dissect from the dura mater and the surrounding tissues. From the ultrastructural observation of the fibroblasts, the nucleus became much bigger and the rough endoplasmic reticulum was much more plentiful in the control group than that in the experimental group. CONCLUSIONS: Polylactic acid glue can effectively reduce epidural cicatrization and adhesion.


Assuntos
Cicatriz/prevenção & controle , Ácido Láctico/farmacologia , Laminectomia , Membranas Artificiais , Polímeros/farmacologia , Complicações Pós-Operatórias/prevenção & controle , Aderências Teciduais/prevenção & controle , Animais , Materiais Biocompatíveis , Ácido Láctico/administração & dosagem , Poliésteres , Polímeros/administração & dosagem , Coelhos
20.
J Phys Chem B ; 109(42): 19831-8, 2005 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-16853564

RESUMO

The interaction of methacrylic acid and methyl methacrylate with Si(111)-7 x 7 has been investigated using high-resolution electron energy loss spectroscopy (HREELS) and X-ray photoelectron spectroscopy (XPS). While methacrylic acid chemisorbs dissociatively through O-H bond cleavage, methyl methacrylate is covalently attached to the silicon surface via a [4+2] cycloaddition. The different reaction pathways of these two compounds on Si(111)-7 x 7 demonstrate that the substitution groups play an important role in determining the reaction channels for multifunctional molecules, leading to the desired flexibility in the organic modification of silicon surfaces.


Assuntos
Metacrilatos/química , Silicones/química , Boro/química , Ciclização , Indicadores e Reagentes , Metilmetacrilato/química , Espectrometria por Raios X , Espectroscopia de Perda de Energia de Elétrons , Propriedades de Superfície
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