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1.

Objective

A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapatite (g-HA)/poly(lactide-co-glycolide) (PLGA) carried with autologous mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated.

Methods

A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were observed by intramuscular implantation, as well as the repair of the critical radius defects in rabbits.

Results

After eight weeks post-surgery, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that g-HA/PLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HA/PLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HA/PLGA at 2–8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HA/PLGA, while only fibrous tissues formed in PLGA.

Conclusions

The incorporation of g-HA mainly improved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone formation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds.
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2.

Background

Tumor-derived exosomes were considered to be potential candidates for tumor vaccines because they are abundant in immune-regulating proteins, whereas tumor exosomal miRNAs may induce immune tolerance, thereby having an opposite immune function.

Objective

This study was designed to separate exosomal protein and depleted exosomal microRNAs (miRNAs), increasing the immune activity of exosomes for activating dendritic cell/cytokine-induced killer cells (DC/CIKs) against pancreatic cancer (PC).

Methods

PC-derived exosomes (PEs) were extracted from cultured PANC-1 cell supernatants and then ruptured; this was followed by ultrafiltered exosome lysates (UELs). DCs were stimulated with lipopolysaccharide (LPS), PE, and UEL, followed by co-culture with CIKs. The anti-tumor effects of DC/CIKs against PC were evaluated by proliferation and killing rates, tumor necrosis factor-α (TNF-α) and perforin secretion. Exosomal miRNAs were depleted after lysis and ultrafiltration, while 128 proteins were retained, including several immune-activating proteins.

Results

UEL-stimulated DC/CIKs showed a higher killing rate than LPS- and PE-stimulated DC/CIKs.

Conclusions

miRNA-depleted exosome proteins may be promising agonists for specifically activating DC/CIKs against PC.
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3.

Objective

To report surgical management and favorable outcome in a case with delayed repair of traumatic laser in situ keratomileusis (LASIK) flap dislocation with shrinkage and folds.

Methods

A 30-year-old man with a five-year history of bilateral LASIK experienced blunt trauma to his right eye followed by decreased vision for 5 weeks. The surgical management included initially softening the flap by irrigation with balanced salt solution (BSS). The shrinkage folds were carefully and gently stretched by scraping with a 26-gauge cannula accompanied by BSS irrigation. All of the epithelial ingrowth on the flap inner surface and on the bed was thoroughly debrided by scraping and irrigation. After the flap was repositioned to match its original margin, a soft bandage contact lens was placed.

Results

At his initial visit, slit-lamp microscopy and optical coherence tomography (OCT) showed shrinkage of the LASIK flap with an elevated margin approximately 3 mm above the original position. The flap covered half of the pupil and had multiple horizontal folds. Two months after surgery, the flap remained well positioned with only faint streaks in the anterior stroma. The uncorrected visual acuity of the right eye was 20/20 with a manifest refraction of Plano.

Conclusions

For delayed repair of traumatically dislocated LASIK flaps, sufficient softening by BSS, stretching the shrinkage folds, and thorough debridement of ingrowth epithelium enable resetting the flap and provide satisfactory results.
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4.

Objective

To investigate the stress distribution to the mandible, with and without impacted third molars (IM3s) at various orientations, resulting from a 2000-Newton impact force either from the anterior midline or from the body of the mandible.

Materials and methods

A 3D mandibular virtual model from a healthy dentate patient was created and the mechanical properties of the mandible were categorized to 9 levels based on the Hounsfield unit measured from computed tomography (CT) images. Von Mises stress distributions to the mandibular angle and condylar areas from static impact forces (Load I-front blow and Load II left blow) were evaluated using finite element analysis (FEA). Six groups with IM3 were included: full horizontal bony, full vertical bony, full 450 mesioangular bony, partial horizontal bony, partial vertical, and partial 450 mesioangular bony impaction, and a baseline group with no third molars.

Results

Von Mises stresses in the condyle and angle areas were higher for partially than for fully impacted third molars under both loading conditions, with partial horizontal IM3 showing the highest fracture risk. Stresses were higher on the contralateral than on the ipsilateral side. Under Load II, the angle area had the highest stress for various orientations of IM3s. The condylar region had the highest stress when IM3s were absent.

Conclusions

High-impact forces are more likely to cause condylar rather than angular fracture when IM3s are missing. The risk of mandibular fracture is higher for partially than fully impacted third molars, with the angulation of impaction having little effect on facture risk.
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5.

Objective

The purpose of this study was to determine the role of Ureaplasma urealyticum-derived lipidassociated membrane proteins (LAMPs) in the host innate immune system, specifically their effect on Toll-like receptors (TLRs).

Methods

LAMPs were derived from U. urealyticum strains, and human amniotic epithelial cells (HAECs) were isolated from healthy full-term placentas. Cytokine concentrations were determined by enzyme-linked immunosorbent assay (ELISA) and TLR2 mRNA by real-time PCR. Expression of TLR2 was confirmed by Western blotting and immunohistochemistry.

Results

LAMPs induced HAECs to produce inflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α. Cytokine production was reduced after blocking TLR2 using TLR2 inhibitor (anti-hTLR2-IgA).

Conclusions

LAMPs isolated from U. urealyticum induced TLR2-dependent up-regulation of inflammatory genes and cytokines in HAECs.
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6.
7.

Objectives

The aim of the study is to evaluate the cognitive-enhancing effects of hydrolysate of polygalasaponin (HPS) on senescence accelerate mouse P8 (SAMP8) mice, an effective Alzheimer’s disease (AD) model, and to research the relevant mechanisms.

Methods

The cognitive-enhancing effects of HPS on SAMP8 mice were assessed using Morris water maze (MWM) and step-through passive avoidance tests. Then N-methyl-d-aspartate (NMDA) receptor subunit expression for both the cortex and hippocampus of mice was observed using Western blotting.

Results

HPS (25 and 50 mg/kg) improved the escape rate and decreased the escape latency and time spent in the target quadrant for the SAMP8 mice in the MWM after oral administration of HPS for 10 d. Moreover, it decreased error times in the passive avoidance tests. Western blotting showed that HPS was able to reverse the levels of NMDAR1 and NMDAR2B expression in the cortex or hippocampus of model mice.

Conclusions

The present study suggested that HPS can improve cognitive deficits in SAMP8 mice, and this mechanism might be associated with NMDA receptor (NMDAR)-related pathways.
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8.

Objective

Bovine endometritis is one of the most common reproductive disorders in cattle. The aim of this study was to investigate the anti-inflammation potential of punicalagin in lipopolysaccharide (LPS)-induced bovine endometrial epithelial cells (bEECs) and to uncover the underlying mechanisms.

Methods

bEECs were stimulated with different concentrations (1, 10, 30, 50, and 100 μg/ml) of LPS for 3, 6, 9, 12, and 18 h. MTT assay was used to assess cell viability and to identify the conditions for inflammatory injury and effective concentrations of punicalagin. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to assess gene expression of pro-inflammatory cytokines. Western blotting was used to assess levels of inflammation-related proteins.

Results

Treatment of bEECs with 30 μg/ml LPS for 12 h induced cell injury and reduced cell viability. Punicalagin (5, 10, or 20 μg/ml) pretreatment significantly decreased LPS-induced productions of interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor-α (TNF-α) in bEECs. Molecular research showed that punicalagin inhibited the activation of the upstream mediator nuclear factor-κB (NF-κB) by suppressing the production of inhibitor κBα (IκBα) and phosphorylation of p65. Results also indicated that punicalagin can suppress the phosphorylation of mitogen-activated protein kinases (MAPKs) including p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK).

Conclusions

Punicalagin may attenuate LPS-induced inflammatory injury and provide a potential option for the treatment of dairy cows with Escherichia coli endometritis.
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9.
10.

Purpose

Metalloproteinases are a key component of the pathogenesis of abdominal hernias. Obesity is considered a risk factor in herniogenesis and hernia recurrence. The aim of this study was to evaluate the serum concentrations of metalloproteinase-2 (MMP-2), MMP-9, MMP-13, and adiponectin in morbidly obese and nonoverweight controls.

Materials and methods

The participants were recruited from among patients undergoing bariatric and non-bariatric surgery and divided into two groups: I (body mass index (BMI)≥35 kg/m2, n=40) and II (BMI<25 kg/m2, n=30). Serum concentrations of MMP-2, MMP-9, MMP-13, and adiponectin were measured using enzyme-linked immunosorbent assay (ELISA).

Results

A statistically significant difference between groups was observed for MMP-2 concentration. The median MMP-9 concentration was higher in the obese group, but the difference was not statistically significant. Median MMP-13 concentrations did not differ between groups. Serum adiponectin concentration was insignificantly higher in the non-obese group.

Conclusions

The elevated serum MMP-2 and MMP-9 concentrations in obese individuals may be related to the higher incidence of incisional hernias in this population.
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11.

Objectives

To observe the surface characteristics and mechanical behavior of retrieved microimplants under clinically simulating experimental conditions and to investigate the feasibility of reuse of microimplants.

Materials and methods

The microimplants, inserted at different angles, were retrieved from the patients (RMIP) and the artificial bone (RMIA). Surface characteristics, including morphologic changes of tips and thread edges, length reduction, and surface compositional variation, were evaluated using a field emission scanning electron microscope, a stereoscopic microscope, and energy-dispersive X-ray spectroscopy, respectively. Mechanical behavior comprising maximum insertion torque (MIT) and insertion time was tested with the artificial bone under clinically simulating conditions.

Results

The tips and thread edges were worn out to various degrees in retrieved microimplants and thin deposits were observed on the surface in the RMIP group. Traces of foreign elements, such as iron, sulphur, and calcium, were detected on the surface of RMIP. Both MIT and insertion time of retrieved microimplants were increased compared to their initial use, and were much greater in RMIP. The increases of MIT were seen in all groups inserted at the insertion angle of 45° compared with 90°, although the differences were not statistically significant.

Conclusions

Retrieved microimplants exhibited different degrees of changes on surface characteristics and mechanical behavior, with more changes in RMIP. The reuse of microimplants for immediate relocation in the same patient may be acceptable; however, postponed relocation and allogeneic reuse of microimplants are not recommended in clinical practice.
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12.

Objective

The aim of the current study was to evaluate the effect of ultraviolet (UV) photofunctionalization of dental titanium implants with exposure to the oral cavity on osseointegration in an animal model.

Methods

Forty-eight titanium implants (Camlog® Conelog® 4.3 mmx9.0 mm) were placed epicrestally into the edentulous jaws of three minipigs and implant stability was assessed by measuring the implant stability quotient (ISQ). Prior to implantation half of the implants were photofunctionalized with intense UV-light. After three months, the implants were exposed and ISQ was measured again. After six months of implant exposure, the minipigs were sacrificed and the harvested specimens were analyzed using histomorphometric, light, and fluorescence microscopy.

Main results

Forty-two of 48 implants osseointegrated. The overall mean bone-implant contact area (BIC) was (64±22)%. No significant differences were found in BIC or ISQ value (multivariate analysis of variance (MANOVA), P&gt;0.05) between implants with and without exposure to UV photofunctionalization.

Conclusions

No significant effects were observed on osseointegration of dental titanium implants nine months after exposure of UV photofunctionalization.
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13.
14.

Objective

The present study aims at determining the stability of a popular type 2 diabetes rat model induced by a high-fat diet combined with a low-dose streptozotocin injection.

Methods

Wistar rats were fed with a high-fat diet for 8 weeks followed by a one-time injection of 25 or 35 mg/kg streptozotocin to induce type 2 diabetes. Then the diabetic rats were fed with regular diet/high-fat diet for 4 weeks. Changes in biochemical parameters were monitored during the 4 weeks.

Results

All the rats developed more severe dyslipidemia and hepatic dysfunction after streptozotocin injection. The features of 35 mg/kg streptozotocin rats more resembled type 1 diabetes with decreased body weight and blood insulin. Rats with 25 mg/kg streptozotocin followed by normal diet feeding showed normalized blood glucose level and pancreatic structure, indicating that normal diet might help recovery from certain symptoms of type 2 diabetes. In comparison, diabetic rats fed with high-fat diet presented decreased but relatively stable blood glucose level, and this was significantly higher than that of the control group (P&gt;0.05).

Conclusions

This model easily recovers with normal diet feeding. A high-fat diet is suggested as the background diet in future pharmacological studies using this model.
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15.

Objective

The aim of this study was to formulate polymer-based artesunate nanoparticles for malaria treatment.

Methods

Artesunate was loaded with poly(D,L-lactic-co-glycolic acid) (PLGA) by solvent evaporation from an oil-in-water single emulsion. Nanoparticles were characterized by X-ray diffraction and differential scanning calorimetry analyses. In vivo antimalarial studies at 4 mg/kg were performed on Swiss male albino mice infected with Plasmodium berghei. Hematological and hepatic toxicity assays were performed. In vitro cytotoxicity of free and encapsulated artesunate (Art-PLGA) to cell line RAW 264.7 was determined at concentrations of 7.8–1000 μg/ml.

Results

The particle size of the formulated drug was (329.3±21.7) nm and the entrapment efficiency was (38.4±10.1)%. Art-PLGA nanoparticles showed higher parasite suppression (62.6%) compared to free artesunate (58.2%, P<0.05). Platelet counts were significantly higher in controls (305 000.00±148 492.40) than in mice treated with free artesunate (139 500.00±20 506.10) or Art-PLGA (163 500.00±3535.53) (P<0.05). There was no sign of hepatic toxicity following use of the tested drugs. The half maximal inhibitory concentration (IC50) of Art-PLGA (468.0 μg/ml) was significantly higher (P<0.05) than that of free artesunate (7.3 μg/ml) in the in vitro cytotoxicity assay.

Conclusions

A simple treatment of PLGA-entrapped artesunate nanoparticles with dual advantages of low toxicity and better antiplasmodial efficacy has been developed.
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16.

Objective

In previous studies, Lactobacillus plantarum ZJ316 showed probiotic properties, such as antimicrobial activity against various pathogens and the capacity to significantly improve pig growth and pork quality. The purpose of this study was to reveal the genes potentially related to its genetic adaptation and probiotic profiles based on comparative genomic analysis.

Methods

The genome sequence of L. plantarum ZJ316 was compared with those of eight L. plantarum strains deposited in GenBank. BLASTN, Mauve, and MUMmer programs were used for genome alignment and comparison. CRISPRFinder was applied for searching the clustered regularly interspaced short palindromic repeats (CRISPRs).

Results

We identified genes that encode proteins related to genetic adaptation and probiotic profiles, including carbohydrate transport and metabolism, proteolytic enzyme systems and amino acid biosynthesis, CRISPR adaptive immunity, stress responses, bile salt resistance, ability to adhere to the host intestinal wall, exopolysaccharide (EPS) biosynthesis, and bacteriocin biosynthesis.

Conclusions

Comparative characterization of the L. plantarum ZJ316 genome provided the genetic basis for further elucidating the functional mechanisms of its probiotic properties. ZJ316 could be considered a potential probiotic candidate.
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17.

Objective

Fruit of Phyllanthus emblica Linn. (PE) is widely consumed as a functional food and used as a folk medicine due to its remarkable nutritional and pharmacological effects. Mitomycin C (MMC) and cisplatin (cDDP) are the most widely used forms of chemotherapeutic drug, but their clinical use is limited by their genotoxicity to normal cells. We aimed to determine whether PE has potential to reduce the genotoxicity, while improving the anticancer effect, of MMC and cDDP.

Methods

Cell proliferation was evaluated using the trypan blue exclusion assay and colony-forming assay. Genomic instability (GIN) was measured using the cytokinesis-block micronucleus assay.

Results

Co-treatment (72 h) with PE at 20–320 μg/ml significantly enhanced the efficacy of MMC (0.05 μg/ml) and cDDP (1 μg/ml) against Colo205 colorectal cancer cells (P<0.05), and at 80–320 μg/ml significantly decreased MMCand cDDP-induced GIN and multinucleation in normal colonic NCM460 cells (P<0.05). PE significantly decreased the mitotic index (P<0.01), blocked mitotic progression (P<0.05), and promoted apoptosis (P<0.01) in MMC- and cDDP-treated NCM460 cells, suggesting that PE-mediated inhibition of mitosis and induction of apoptosis may limit the division and survival of highly damaged cells. Also, PE was found to inhibit the clonal expansion of MMC- and cDDP-treated NCM460 cells (P<0.05) and decrease the heterogeneity of the surviving clones.

Conclusions

PE potentiates the anticancer efficacy of MMC and cDDP, while preventing their genotoxicity and inhibiting clonal expansions of unstable genomes in normal cells. These data suggest that PE has the potential to reduce the risk of secondary cancers induced by chemotherapeutics.
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18.
目的:探讨在肾功能正常或轻度受损(肾小球滤过率≥60 ml/(min·1.73 m2))人群中矿物质代谢紊乱与钙化性主动脉瓣疾病的发生和严重性是否相关。创新点:以具有代表性和临床价值的肾功能正常或轻度受损人群为研究对象,首次尝试通过骨转换生物标志物检测探讨钙化性主动脉瓣疾病的可能机制。方法:入选260例经超声心动图诊断钙化性主动脉瓣疾病患者(164例钙化性主动脉瓣硬化,96例钙化性主动脉瓣狭窄)和164例年龄及性别匹配对照组人群,检测矿物质代谢和骨转换生化标志物,应用多因素回归分析矿物质代谢与钙化性主动脉瓣疾病的发生和严重性的关系,并初步探讨可能机制。结果显示,从对照组到钙化性主动脉瓣硬化至狭窄患者,血钙、血磷、碱性磷酸酶和甲状旁腺素(i PTH)水平进行性升高,25羟-维生素D(25-OHD)水平进行性降低,各组间差异具有统计学显著性(P<0.001);同样,骨转换生化标志物骨钙素(BGP)、I型前胶原N端前肽(PINP)和β-胶原特殊序列(β-CTx)水平进行性升高,各组间差异具有统计学显著性(P<0.001)。在钙化性主动脉瓣狭窄患者中,i PTH水平与跨瓣峰值流速和平均跨瓣压差显著正相关,25-OHD则显著负相关。经校正相关因素后,多因素回归分析显示,血钙、血磷、碱性磷酸酶和i PTH水平升高及25-OHD水平下降和钙化性主动脉瓣疾病的发生和严重性密切相关。结论:矿物质代谢紊乱与钙化性主动脉瓣疾病的发生和严重性密切相关,异常骨转换可能是其发生机制。  相似文献   

19.

Objective

This study investigated complementary feeding practices among four ethnic groups (Han, Uygur, Tibetan, and Zhuang) based on a cross-sectional survey in rural western China.

Methods

In 2005, a stratified multistage cluster random sampling method was used to recruit 9712 children (7411 Han, 1032 Uygur, 678 Tibetan, and 591 Zhuang) between 6 and 35 months of age and their mothers from 45 counties in 10 provinces (autonomous regions, municipalities) in western China.

Results

The rates of early introduction (before 6 months) of complementary foods in four ethnic groups (Han, Uygur, Tibetan, and Zhuang) were 71.30%, 95.95%, 82.40%, and 72.30%, respectively. The Infant and Child Feeding Index (ICFI) for Uygur and Tibetan children was lower than that for Han children at all age groups. Uygur children were more likely to have unqualified ICFI compared with Han children in a multivariate logistic regression (odds ratio (OR)=5.138, 95% confidence interval (CI): 4.340–6.084). A higher level of maternal education, greater family wealth, and the availability of complementary feeding educational materials decreased the likelihood of an unqualified ICFI. The nutritional status of children (Han, Tibetan, and Zhuang) with qualified ICFI was better than that for children with unqualified ICFI.

Conclusions

Appropriate interventions are required to improve complementary feeding practices in rural western China.
  相似文献   

20.

Objective

The aim of this study was to evaluate the safety and efficiency of enucleation (EU) for proximal pancreatic non-invasive neoplasms.

Methods

Patients with solitary non-invasive neoplasms in the proximal pancreas from January 1998 to April 2014 at the Second Affiliated Hospital of Zhejiang University, Hangzhou, China were included. Different operations and outcomes were analyzed.

Results

A total of 123 patients were enrolled. Forty patients (32.5%) underwent EU including 18 patients who had tumors close to the main pancreatic duct (MPD). Sixty-one patients (49.6%) had pancreaticoduodenectomy (PD) performed and 22 (17.9%) underwent central pancreatectomy (CP). Pathological outcomes included neuroendocrine tumors, cystic lesions, and solid pseudopapillary tumors. Operation time, intra-operative blood loss, and duration of hospital stay were significantly reduced in the EU group. PD was associated with the greatest complication rate (55.7%), followed by EU (50%) and CP (40.9%), though the pancreatic fistula rate after EU was the highest (50%), especially in patients with tumors larger than 3 cm and tumors close to the MPD. EU had advantages in the preservation of pancreatic parenchyma and endocrine and exocrine function.

Conclusions

EU can be carried out safely and effectively for tumors in the proximal pancreas with improved outcomes compared with standard resections, even if the tumor is larger than 3 cm and close to the MPD.
  相似文献   

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