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1.
ACS Appl Mater Interfaces ; 16(12): 15227-15241, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38498312

ABSTRACT

Biobased-functionalized metal-organic frameworks (Bio-FUN-MOFs) stand out from the crowd of candidates in the flame-retardant field due to their multipathway flame-retardant mechanisms and green synthesis processes. However, exploring and designing Bio-FUN-MOFs tend to counteract the problem of compromising the flame-retardant advantages of MOFs themselves, which inevitably results in a waste of resources. Herein, a strategy in which MOFs are ecologically regulated through acid-base balance is presented for controllable preparation of Bio-FUN-MOFs by two birds with one stone, i.e., higher flame-retardant element loading and retention of more MOF structures. Specifically, the buffer layer is created on the periphery of ZIF-67 by weak etching of biobased alkali arginine to resist the excessive etching of ZIF-67 by phytic acid when loading phosphorus source and to preserve the integrity of internal crystals as much as possible. As a proof of concept, ZIF-67 was almost completely etched out by phytic acid in the absence of arginine. The arginine and phytic acid-functionalized ZIF-67 with yolk@shell structure (ZIF@Arg-Co-PA) obtained by this strategy, as a biobased flame retardant, reduces fire hazards for polyurea composites. At only 5 wt % loading, ZIF@Arg-Co-PA imparted polyurea composites with a limiting oxygen index of 23.2%, and the peaks of heat release rate, total heat release, and total smoke production were reduced by 43.8, 32.3, and 34.3%, respectively, compared to neat polyurea. Additionally, the prepared polyurea composites have acceptable mechanical properties. This work will shed light on the advanced structural design of polymer composites with excellent fire safety, especially environmentally friendly and efficient biobased MOF flame retardants.

2.
ACS Appl Mater Interfaces ; 16(6): 7617-7630, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38315971

ABSTRACT

Up to now, metal-organic frameworks (MOFs) with open nanostructures have shown outstanding capabilities in trapping smoke particles compared to the original MOFs. However, only a few MOF-based strategies have been reported to synthesize hierarchical porous cages thus far, which are mainly restricted to environmentally unfriendly wet-chemical liquid methods. Herein, as a proof-of-concept, a gas-steamed metal-organic framework approach was designed to fabricate a series of cheeselike open cages with hierarchical porosity. Briefly, zeolitic imidazolate framework-67 (ZIF-67) and phytic acid were employed as precursor and etchant, respectively. Abandoning the conventional wet-chemical method, the coordination bond of ZIF-67 was cleaved by acidic steam, forming an open framework with a high specific surface area and a hierarchical porous structure. The universality of this method was also confirmed by the selection of different etchants. Impressively, they also show outstanding fume-toxic adsorption capability and labyrinth effects based on abundant and complex porous channels. At only 5 wt % loading, Co3O4@open ZIF-67 cage-2 (Co3O4@OZC-2) imparted polyurea (PUA) composites with a 21.2% limiting oxygen index, and the peak of heat release rate, total heat release, and total smoke production were reduced by around 37.5, 25.5, and 40.4%, respectively, compared to neat PUA. This work will shed light on the advanced structural design of polymer composites with high fire safety, especially smoke suppression performance, so as to obtain more feasible applications.

3.
Small ; 20(12): e2307492, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37946679

ABSTRACT

A dodecahedral superstructure consisting of a single layer of Janus spheres containing ZIF-67 nanodots is prepared by in situ polymerization, with ZIF-67 and bio-based phytic acid (PA) as templates and dopants. It is used to improve the flame retardant, electromagnetic (EMI) shielding, and thermal conductivity properties of polyurea (PUA). By adding 5 wt% polyaniline@cobalt phytate-2.0 (PANI@Co-PA-2.0), the peak of heat release rate and the peak of smoke production rate are reduced by 54.9 and 59.9%, respectively. The peak of CO and CO2 production also decreased by 46.2 and 53.1%, respectively. A decrease in the absorption intensity of aliphatic and aromatic volatiles is also observed. The fire safety of PUA is greatly improved. In addition, PUA/PANI@Co-PA-2.0 exhibits an EMI shielding capability of 22.4 dB with the help of reduced graphene oxide, which confirms the possibility of PUA material application in the field of electromagnetic shielding. The 5 wt% filler increases the tensile strength of the PUA matrix to 6.3 MPa, and the composite material obtains good thermal conductivity. This work provides a viable method for the preparation of a flame-retardant, conductive, and electromagnetic refractory PUA substrate.

4.
Polymers (Basel) ; 15(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37447562

ABSTRACT

A Fe-N conjugated organic polymer (SMP-Fr-Py) was prepared from ferrocene and pyrrole using a Scholl coupling reaction, which significantly improved the performance of Cr(VI) removal compared to the polymer (HCP-Fr-Py) prepared by adding the cross-linker formaldehyde dimethyl acetal (FDA). The results showed that at a pH of 2 and at 25 °C, the removal of Cr(VI) reached 90% for SMP-Fr-Py and only 58% for HCP-Fr-Py after 20 min of reaction. Subsequently, 99% and 78% were achieved after 120 min of reaction, respectively. The test results showed that the removal reaction followed a pseudo-second-order kinetic model. The removal efficiency decreased with increasing solution pH and initial Cr(VI) concentration, but increased with increasing SMP-Fr-Py dosage, reaching three cycles. The characterization of the reaction complexes and measurements of Cr species conversion revealed the near absence of Cr(VI) species in the solution. Approximately 38% of Cr(VI) was found to be adsorbed on the material surface, with another fraction present in solution (24%) and on the material surface (38%) in the form of Cr(III). The overall study showed that the direct connection of ferrocene and pyrrole in SMP-Fr-Py through C-C bonding increased the conjugated structure of the polymer backbone, which facilitated electron transfer and transport. Furthermore, the Fe-N elements worked synergistically with each other more easily, which improved the removal performance of Cr(VI) and provided a reference for the subsequent work.

5.
Polymers (Basel) ; 15(12)2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37376393

ABSTRACT

The synthesis of efficient and sustainable heterogeneous Pd-based catalysts has been an active field of research due to their crucial role in carbon-carbon coupling reactions. In this study, we developed a facile and eco-friendly in situ assembly technique to produce a PdFe bimetallic hyper-crosslinked polymer (HCP@Pd/Fe) to use as a highly active and durable catalyst in the Ullmann reaction. The HCP@Pd/Fe catalyst exhibits a hierarchical pore structure, high specific surface area, and uniform distribution of active sites, which promote catalytic activity and stability. Under mild conditions, the HCP@Pd/Fe catalyst is capable of efficiently catalyzing the Ullmann reaction of aryl chlorides in aqueous media. The exceptional catalytic performance of HCP@Pd/Fe is attributed to its robust absorption capability, high dispersion, and strong interaction between Fe and Pd, as confirmed by various material characterizations and control experiments. Furthermore, the coated structure of a hyper-crosslinked polymer enables easy recycling and reuse of the catalyst for at least 10 cycles without any significant loss of activity.

6.
J Colloid Interface Sci ; 643: 489-501, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37088052

ABSTRACT

The loading treatment of phosphorus flame retardants can mitigate their migration and plasticization effect. However, designing suitable carriers has remained a great challenge. Herein, two kinds of Co-based isomers, namely cobalt-cobalt layered double hydroxides (CoCo-LDH) and cobalt basic carbonate (CBC), were synthesized by employing ZIF-67 as a self-template, assemblied into two different nanostructures namely multi-yolk@shell CBC@CoCo-LDH (m-CBC@LDH) and solid CBC nanoparticles by facilely tuning the reaction time, which were employed as carriers, respectively. Subsequently, triphenyl phosphate (TPP)-loaded m-CBC@LDH (m-CBC-P@LDH) was prepared using TPP as the guest. The m-CBC@LDH with high specific surface area and hollow structure exhibited up to more than 30% of TPP loading. The peak of heat release rate and total heat release of polyurea composite blended with 5 wt% m-CBC-P@LDH reduced by 41.7% and 20.6% respectively, and the mechanical properties were less damaged. This work complements a feasible approach for preparation of metal-organic frameworks-derived flame retardant carriers.

7.
ACS Appl Mater Interfaces ; 14(43): 49326-49337, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36270017

ABSTRACT

The direct coordination between polyhedral oligomeric silsesquioxane (POSS) and Co forms an assembly of nanoparticles with low specific surface area and leads to a poor dispersion state in the epoxy resin matrix, resulting in unsatisfactory flame-retardant efficiency. Metal-organic frameworks (MOFs), for instance, ZIF-67, provide not only the cobalt element but also the porous framework that endows the nanocomposite of MOFs and POSS with high specific surface area and abundant Co sites in the silica skeleton. Herein, ZIF-67 is hybridized with octacarboxyl POSS, resulting in the removal of the alkaline ligand to form novel metal POSS-organic frameworks (MPOFs). The size differences for organic groups and silica nanocages of POSS vs. micropores of ZIF-67 gave rise to a reverse click reaction, reforming octavinyl POSS isolated on the outer surface of the Co complex, which could be further modified by a phosphorous flame retardant using an addition reaction. The obtained MPOFs-P with 2 wt % loading in epoxy resin could improve the limiting oxygen index value of the composites to 27.0% and pass the V-0 rating in the UL-94 test. Meanwhile, the peaks of the heat release rate and especially the total smoke production were reduced by 46.6 and 25.2%, respectively. The robust char layer reduces the emission of toxic gas CO by 39.8%. The above epoxy product with promising flame retardancy also improved mechanical properties, thanks to the filler with a unique nanostructure. The ingenious work offers enlightenment for the hybridization method of MOFs and POSS to fabricate a multielement flame-retardant system for epoxy resin with high efficacy.

8.
Sensors (Basel) ; 22(17)2022 Aug 27.
Article in English | MEDLINE | ID: mdl-36080916

ABSTRACT

Epilepsy is a common neurological disease worldwide, characterized by recurrent seizures. There is currently no cure for epilepsy. However, seizures can be controlled by drugs and surgeries in about 70% of epileptic patients. A timely and accurate prediction of seizures can prevent injuries during seizures and improve the patients' quality of life. In this paper, we proposed an intelligent epileptic prediction system based on Synchrosqueezed Wavelet Transform (SWT) and Multi-Level Feature Convolutional Neural Network (MLF-CNN) for smart healthcare IoT network. In this system, we used SWT to map EEG signals to the frequency domain, which was able to measure the energy changes in EEG signals caused by seizures within a well-defined Time-Frequency (TF) plane. MLF-CNN was then applied to extract multi-level features from the processed EEG signals and classify the different seizure segments. The performance of our proposed system was evaluated with the publicly available CHB-MIT dataset and our private ZJU4H dataset. The system achieved an accuracy of 96.99% and 94.25%, a sensitivity of 96.48% and 97.76%, a specificity of 97.46% and 94.07% and a false prediction rate (FPR/h) of 0.031 and 0.049 FPR/h on the CHB-MIT dataset and the ZJU4H dataset, respectively.


Subject(s)
Epilepsy , Wavelet Analysis , Algorithms , Delivery of Health Care , Electroencephalography , Epilepsy/diagnosis , Humans , Quality of Life , Seizures/diagnosis
9.
ACS Appl Mater Interfaces ; 14(12): 14805-14816, 2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35290025

ABSTRACT

Nanomaterials derived from metal-organic frameworks (MOFs) are highly promising as future flame retardants for polymeric materials. The precise control of the interface for polymer nanocomposites is taking scientific research by storm, whereas such investigations for MOF-based nanofillers are rare. Herein, a novel yolk-double shell nanostructure (ZIF-67@layered double hydroxides@polyphophazenes, ZIF@LDH@PZS) was subtly designed and introduced into epoxy resin (EP) as a flame retardant to fill the vacancy of yolk/shell construction in the field. Meanwhile, the interface of the polymer nanocomposites can be further accurately tailored by the outermost layer of the nanofillers from PZS to Ni(OH)2 (NH), by which hollow nanocages with treble shells (LDH@PZS@NH) were obtained. It is remarkably interesting that LDH@PZS@NH endows the EP with the lowest peak of heat release rate in the cone calorimeter test, but the total heat and smoke releases (THR and TSP) of the nanocomposites are even higher than those of the neat polymer. In contrast, EP blended with ZIF@LDH@PZS shows outstanding comprehensive performance: with 2 wt.%, the limiting oxygen index is increased to 29.5%, and the peak heat release rate is reduced by 26.0%. The impact and flexural strengths are slightly lowered, while the storage modulus is enhanced remarkably compared with that for neat EP. The flame retardant mechanism is systematically explored focusing on the interfacial interactions of different hybrids within the epoxy matrix, ushering in a new stage of study of nanostructural design-guided interface manipulation in MOF-based polymer nanocomposites.

10.
ESC Heart Fail ; 9(2): 1050-1060, 2022 04.
Article in English | MEDLINE | ID: mdl-34970865

ABSTRACT

AIM: Long non-coding RNAs (lncRNAs) are known to participate in various human diseases, while the role of X inactive-specific transcript (XIST) binding microRNA-340-5p (miR-340-5p) remains seldom studied. We aim to identify the role of the XIST/miR-340-5p/cyclin D1 (CCND1) axis in the myocardial ischaemia-reperfusion injury (MIRI). METHODS AND RESULTS: The mouse MIRI models were established. The expression of XIST, miR-340-5p, and CCND1 in mouse myocardial tissues in MIRI mice was assessed. The MIRI mice were respectively treated with altered XIST, miR-340-5p, or CCND1. The changes of myocardial enzyme activity were assessed, and the cardiac function was evaluated. Myocardial pathological changes, cardiomyocyte apoptosis and related apoptotic factors, oxidative stress and inflammatory factors were observed in myocardial tissues in mice with MIRI. The binding relationships between XIST and miR-340-5p, and between miR-340-5p and CCND1 were confirmed. XIST and CCND1 were up-regulated while miR-340-5p was down-regulated in MIRI mice. Silenced XIST could elevated miR-340-5p expression and reduced CCND1 expression, so as to promoted cardiac function and suppressed myocardial enzyme activity, ameliorated pathological changes, decelerated cardiomyocyte apoptosis by elevating Bcl-2 but reducing the levels of Bax and Caspase-3, attenuated inflammatory response by repressing IL-6 and TNF-α levels, and mitigated oxidative stress by reducing MDA contents and increasing CAT, GSH-Px, and SOD levels in MIRI mice. XIST sponged miR-340-5p and miR-340-5p targeted CCND1. CONCLUSIONS: Knockdown of XIST up-regulates miR-340-5p to relieve MIRI via inhibiting CCND1.


Subject(s)
MicroRNAs , Myocardial Reperfusion Injury , RNA, Long Noncoding/metabolism , Animals , Cyclin D1/genetics , Cyclin D1/metabolism , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Myocardial Reperfusion Injury/genetics , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/pathology , Myocardium/pathology , RNA, Long Noncoding/genetics
11.
Front Pharmacol ; 13: 1045561, 2022.
Article in English | MEDLINE | ID: mdl-36699079

ABSTRACT

Background: The role of antihypertensive drugs in inducing hyperuricaemia and gout has been a long-term concern in clinical practice. However, clinical studies regarding this issue are limited in number and have yielded inconsistent results. We comprehensively evaluated the association between various antihypertensive drugs and the occurrences of hyperuricaemia, gout and related adverse events (AEs) using the FDA Adverse Event Reporting System (FAERS), aiming to guide the selection of antihypertensive drugs with a goal of minimizing the risk of hyperuricaemia, gout and related AEs. Methods: We used OpenVigil 2.1 to query the FAERS database. Hyperuricaemia, gout and related AEs were defined by 5 Preferred Terms: hyperuricaemia, gout, gouty arthritis, gouty tophus and urate nephropathy. Disproportionality analysis was performed, and a positive signal indicated an association between AEs and antihypertensive drugs. Results: The numbers of antihypertensive drugs with positive signals for hyperuricaemia, gout, gouty arthritis, gouty tophus and urate nephropathy were 46, 66, 27, 8 and 6, respectively. These drugs included diuretics, antihypertensive drugs with central action, α blockers, ß blockers, α and ß blockers, calcium channel blockers, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, renin inhibitors, vasodilators, and compound preparations. Furthermore, 42 antihypertensive drugs had positive signal for more than one AEs. Conclusion: Our study suggests that some potassium-sparing diuretics, calcium channel blockers and losartan may be associated with increased risk of hyperuricaemia, gout or related AEs, which is inconsistent with most previous studies. Moreover, Our study also suggests that some antihypertensive drugs with central action, α and ß blockers, renin inhibitors and vasodilators may be associated with increased risk of hyperuricaemia, gout or related AEs, which has not been reported in previous studies. These findings complement real-world evidence on the potential risks of hyperuricaemia, gout and related AEs associated with antihypertensive drugs.

12.
Polymers (Basel) ; 13(16)2021 Aug 09.
Article in English | MEDLINE | ID: mdl-34451186

ABSTRACT

Developing superior properties of epoxy resin composites with high fire resistance, light smoke, and low toxicity has been the focus of the research in the flame-retardant field. In particular, it is essential to decrease the emissions of toxic gases and smoke particles generated during the thermal decomposition of epoxy resin (EP) to satisfy the industrial requirements for environmental protection and safety. Consequently, the PZS@ZIF-67 composite was designed and synthesized by employing the hydroxyl group-containing polyphosphazene (poly(cyclotriphosphazene-co-4,4'-dihydroxydiphenylsulfone), PZS) as both the interfacial compatibility and an in situ template and the ZIF-67 nanocrystal as a nanoscale coating and flame-retardant cooperative. ZIF-67 nanocrystal with multidimensional nanostructures was uniformly wrapped on the surface of PZS microspheres. Subsequently, the acquired PZS@ZIF-67 composite was incorporated into the epoxy resin to prepare composite samples for the study of their fire safety, toxicity suppression, and mechanical performance. Herein, the EP/5% PZS@ZIF-67 passed the V-0 rating in a UL-94 test with a 31.9% limit oxygen index value. More precisely, it is endowed with a decline of 51.08%, 28.26%, and 37.87% of the peak heat release rate, the total heat release, and the total smoke production, respectively. In addition, the unique structure of PZS@ZIF-67 microsphere presented a slight impact on the mechanical properties of EP composites at low loading. The PZS@ZIF-67 possible flame-retardant mechanism was speculated based on the analysis of the condensed phase and the gas phase of EP composites.

13.
BMC Immunol ; 22(1): 13, 2021 02 16.
Article in English | MEDLINE | ID: mdl-33593275

ABSTRACT

BACKGROUND: CD100 is an immune semaphorin family member that highly expressed on T cells, which take part in the development of acute myocardial infarction (AMI). Matrix metalloproteinases (MMPs) are important mediators for membrane-bound CD100 (mCD100) shedding from T cells to generate soluble CD100 (sCD100), which has immunoregulatory effect on T cells. The aim of this study was to investigate modulatory role of CD100 on CD8+ T cell activity in AMI patients. METHODS: Peripheral sCD100 and MMP-2 level, as well as mCD100 level on T cells was assessed in patients with stable angina pectoris (SAP), unstable angina pectoris (UAP), and AMI. The regulatory function of MMP-2 on mCD100 shedding, sCD100 formation, and cytotoxicity of CD8+ T cells was analyzed in direct and indirect contact co-culture system. RESULTS: AMI patients had higher peripheral sCD100 and lower mCD100 expression on CD8+ T cells in comparison with SAP, UAP, and controls. CD8+ T cells in AMI patients showed elevated direct cytotoxicity, enhanced cytokine production, and increased perforin/granzyme B secretion. Recombinant sCD100 stimulation promoted cytolytic function of CD8+ T cells in controls and AMI patients. Furthermore, AMI patients also had elevated circulating MMP-2 level. Recombinant MMP-2 stimulation induced mCD100 shedding from CD8+ T cells and sCD100 generation, resulting in enhancement of CD8+ T cell cytotoxicity in AMI patients. CONCLUSION: Up-regulation of MMP-2 might contribute to elevation of mCD100 shedding and sCD100 formation, leading to increased cytotoxicity CD8+ T cells in AMI patients.


Subject(s)
Antigens, CD/immunology , CD8-Positive T-Lymphocytes/immunology , Myocardial Infarction/immunology , Semaphorins/immunology , Aged , Antigens, CD/metabolism , CD8-Positive T-Lymphocytes/metabolism , Female , Humans , Lymphocyte Activation/immunology , Male , Matrix Metalloproteinase 2/blood , Matrix Metalloproteinase 2/immunology , Middle Aged , Myocardial Infarction/metabolism , Protein Isoforms/immunology , Protein Isoforms/metabolism , Semaphorins/metabolism
14.
Polymers (Basel) ; 12(11)2020 Oct 29.
Article in English | MEDLINE | ID: mdl-33138265

ABSTRACT

Derivatives of 3,9-dichloro-2,4,8,10-tetraoxa-3,9-diphosphaspiro-[5,5]undecane-3,9-dioxide (SPDPC) are of increasing interest as flame retardants for polymeric materials. In addition, SPDPC is also an important intermediate for the preparation of intumescent flame retardants (IFRs). However, low efficiency and undesirable dispersion are two major problems that seriously restrain the application of IFRs as appropriate flame retardants for polymer materials. Usually, the functionalization or modification of SPDPC is crucial to acquiring high-performance polymer composites. Here, a small molecule spirocyclic flame retardant diphenylimidazole spirocyclic pentaerythritol bisphosphonate (PIPC) was successfully prepared through the substitution reaction between previously synthesized intermediate SPDPC and 2-phenylimidazole (PIM). Phenyl group and imidazole group were uniformly anchored on the molecular structure of SPDPC. This kind of more uniform distribution of flame retardant groups within the epoxy matrix resulted in a synergistic flame retardant effect and enhanced the strength of char layers to the epoxy composites, when compared to the unmodified epoxy. The sample reached a limiting oxygen index (LOI) of 29.7% and passed with a V-0 rating in the UL 94 test with the incorporation of only 5 wt % of as-prepared flame retardant PIPC. Moreover, its peak of heat release rate (pHRR) and total heat release (THR) decreased by 41.15% and 21.64% in a cone calorimeter test, respectively. Furthermore, the addition of PIPC has only slightly impacted the mechanical properties of epoxy composites with a low loading.

15.
Polymers (Basel) ; 12(1)2020 Jan 06.
Article in English | MEDLINE | ID: mdl-31935810

ABSTRACT

A new strategy for the preparation of an integrated three-source intumescent flame retardant (IFR) has been developed to improve the flame-retardant and smoke suppression performance of epoxy resin (EP) with a synergistic flame retardant effect. Herein, the synthesis of a macromolecular spirocyclic phosphorus/nitrogen-containing IFR poly sulfonamide spirocyclic pentaerythritol bisphosphonate (SAPC) is reported via a two-step method that uses pentaerythritol, phosphorus oxychloride and sulfonamide (SAA) as raw materials. Subsequently, the SAPC was incorporated into EP to prepare the composite to investigate its thermal stability, flame retardancy, and smoke suppression performance. Herein, a differential scanning calorimetry (DSC) analysis showed that the addition of SAPC increased the glass transition temperature (Tg) of the composite. Cone test results indicated that the incorporation of 8 wt % SAPC significantly improved the flame-retardant performance for the composite, with a 43.45% decrease in peak of heat release rate, a 28.55% reduction in total heat release, and a 30.04% decrease in total smoke release. Additionally, the composite received the V-0 rating in a UL-94 vertical burning test, accompanied by the "blowout" phenomenon. After the addition of SAPC, the amount of flammable gas products from the EP composite decomposition was obviously suppressed, and the amount of non-flammable as was increased. All of this suggests a good dilution role of SAPC. There are enough reasons to believe that the enhanced flame-retardant and toxicity suppression performance for the EP composite can be attributed to the good coordination of carbonization agent, acid source, and blowing agent in the SAPC structure.

16.
Zhongguo Gu Shang ; 32(11): 991-996, 2019 Nov 25.
Article in Chinese | MEDLINE | ID: mdl-31870045

ABSTRACT

OBJECTIVE: To explore mid-term clinical efficacy and effect on adjacent segment degeneration of Wallis and Coflex interspinous implants for lumbar degenerative diseases. METHODS: From January 2011 to January 2013, 55 patients with L4, 5 degenerative lumbar spine diseases treated with interspinous devices were retrospectively analyzed, including 31 males and 24 females aged from 25 to 67 years old with an average of 43.3 years old; 21 patients were lumbar spinal stenosis and 34 patients were lumbar disc herniation. All patients were divided into Wallis group (33 cases) and Coflex group (22 cases) according to the interspinous fixation system. Visual analogue scale(VAS) was used to evaluate low back pain and lower limb pain, Japanese Orthopedic Association(JOA) score and Oswestry Disability Index(ODI) score were used to evaluate lumbar function. Surgical segment and adjacent segments, range of motion(ROM), disc height and the Pfirrmann grade of upper the adjacent segments were compared before and after operation. RESULTS: Fifty-five patients were followed up from 48 to 72 months with an average of 60.4 months. VAS score of low back pain and lower limb pain, JOA and ODI score of lumbar at 48 months after operation were improved than before operation between two groups(P<0.01), but there was no statistical difference for group comparisons(P>0.05). ROM, disc height of surgical segments were significantly lower than those before operation between two groups (P<0.05), while ROM of the upper and lower adjacent segments and disc height did not change significantly (P>0.05). There was no significant difference in ROM and disc height for group comparisons(P>0.05). There was no change in Pfirrmann grade of the upper adjacent segment degeneration between two groups(P>0.05). Four patients with primary lumbar disc herniation had a recurrence of 1 to 3 years after operation, including 3 in Wallis group and 1 in Coflex group, with an average age of 35.2 years old. CONCLUSIONS: Wallis and Coflex interspinous implants have the similar mid-term efficacy for the treatment of lumbar degenerative diseases, and could delay adjacent segment degeneration, but could not prevent recurrence of disc herniation.


Subject(s)
Intervertebral Disc Degeneration , Spinal Fusion , Adult , Aged , Female , Follow-Up Studies , Humans , Lumbar Vertebrae , Male , Middle Aged , Retrospective Studies , Treatment Outcome
17.
Exp Ther Med ; 10(6): 2319-2324, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26668635

ABSTRACT

Acute myocardial infarction (AMI) is among the most serious cardiovascular diseases and is a leading cause of mortality in developed countries. Previous studies have indicated the central role played by the bromodomain (BRD) proteins, which belong to the BRD and extra-terminal (BET) family, in gene control during heart failure pathogenesis. In addition, BET inhibition has been shown to suppress cardiomyocyte hypertrophy. However, the role of BET proteins in myocardial infarction remains unclear. The present study aimed to investigate whether BETs inhibition mitigates AMI, and explore the molecular mechanism underlying this effect. A rat model of acute myocardial infarction was established, and rats were divided into the sham, AMI and AMI + JQ1 groups. JQ1, a well-known selective BRD inhibitor, was used to suppress BET domain family activity. The mRNA and protein expression levels of BRD2, BRD3 and BRD4 were evaluated using quantitative polymerase chain reaction and western blot analysis, respectively. In addition, the expression levels of markers of cardiac damage were determined using commercial kits. The results indicated that BRD2 and BRD4 mRNA and protein expression levels were significantly increased in the AMI group compared with those in the sham group. In addition, BET inhibition decreased AMI damage in vivo by reversing cardiac function injury, decreasing serum lactate dehydrogenase and creatine kinase-MB isozyme activity, in addition to decreasing the expression levels of high-sensitivity C-reactive protein and interleukin-6. Furthermore, the results suggested that Toll-like receptor 4 (TLR4) signaling was activated by the increased expression of TLR4, TNF receptor-associated factor 6 (TRAF6) and nuclear factor (NF)-κB during AMI. However, JQ1 treatment suppressed TLR4 signaling activation. In conclusion, the present results demonstrated that the inhibition of BET family proteins suppresses AMI, and that this effect was partially mediated by the inhibition of TLR4/TRAF6/NF-κB signaling.

18.
Dalton Trans ; 44(31): 13906-13, 2015 Aug 21.
Article in English | MEDLINE | ID: mdl-26154277

ABSTRACT

Novel dual-porous carbon-supported palladium nanoparticle (Pd NP) catalysts were prepared by sequential carbonization and reduction of microporous organic polymer-encaged PdCl2. The diverse pore structure of microporous organic polymers provides a reservoir for the palladium precursors and prevents Pd NPs from sintering during the carbonization and reaction. The microporous structure has a significant effect on the size and dispersion of palladium NPs. The average size of the Pd NPs (in the range of 4-6 nm) was tuned by changing the pore size distribution and the carbonization temperature. The resulting carbon-supported Pd NPs were characterized by TEM, BET, XRD, and XPS and the Pd loading was calculated by AAS. The encaged Pd NP catalysts prepared by this methodology exhibited outstanding stability and reusability in the Heck reaction and could be reused at least 10 times without appreciable loss of activity.


Subject(s)
Carbon/chemistry , Metal Nanoparticles/chemistry , Palladium/chemistry , Catalysis , Particle Size , Porosity , Temperature
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