Three-dimensional structure and cytokine distribution of platelet-rich fibrin

OBJECTIVES: Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1) can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. METHODS: Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg); it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. RESULTS: Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5) to low at the plasma end (p=0.19). Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. CONCLUSION: Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians

Gender-Differential Associations between Attention Deficit and Hyperactivity Symptoms and Youth Health Risk Behaviors

Attention deficit and hyperactivity disorder (ADHD) is one of the common developmental disorders that generally receives clinical attention at learning ages, and some symptoms may persist in young adulthood.1 Past research has demonstrated a consistent association between ADHD and youth health risk behaviors (e.g., cigarette smoking), which often develop during adolescence and contribute to early morbidity and mortality among young adults.2 However, ADHD symptoms are not routinely screened in adolescents and emerging adults during their visits to healthcare providers.3 The six-item Adult Self-Report Scale (ASRS-6) for ADHD has been validated in the young population for screening purposes.4 This short form is time-saving and also provides a comparable predictivity of ADHD diagnosis as that of the original long version.5 Although accumulating evidence has demonstrated the association between ADHD symptoms and youth health risk behaviors, this issue has scarcely been explored in the Taiwanese youth population.6 Therefore, this study was conducted to validate the psychometric property of the Chinese version of ASRS-6 and examine the gender-stratified association between ADHD symptoms and youth health risk behaviors

The flow back tracing and DDoS defense mechanism of the TWAREN defender cloud

The TWAREN Defender Cloud is a distributed filter platform on thenetwork backbone to help defending our connecting institutions against maliciousnetwork attacks. By combining the security reports from participating schools, thissystem can block the incoming threats from the entry points, thus it helps protectingall connecting institutions in the most economic and effective way. This paper aimedat explaining the analyzer design, its mechanism to back trace DDoS attack flows totheir entry points and the defense mechanism it provides to block the threats

Electrospun Co3O4 nanofiber as an efficient heterogeneous catalyst for activating peroxymonosulfate in water

Even though Co3O4 is the most conventional heterogeneous catalyst for activating peroxymonosulfate (PMS), Co3O4 nanoparticles (NPs) aggregate severely, especially in water, losing their catalytic activities. In the present study, an electrospinning technique is employed to prepare Co3O4 nanofiber (CONF), in which severe aggregation of Co3O4 NPs can be prevented as Co3O4 NPs are specifically configured into fibers, rendering a much higher surface area and porosity than conventional Co3O4 NPs. When decolorization of Acid Red 27 (AR) is employed as a model test for PMS activation, CONF exhibits considerably higher catalytic activities than the commercial Co3O4 NPs for activating PMS to decolorize AR completely in 15 min with a rate constant of 0.210 min−1. The Ea of AR decolorization by CONF-activated PMS is 43.5 kJ/mol, which is also lower than several reported studies. CONF can be also re-used to activate PMS over multiple cycles. AR degradation is confirmed to involve with sulfate radicals via examining effects of radical scavengers and Electron Paramagnetic Resonance analysis. The findings obtained in this study successfully demonstrate that the electrospinning technique can be utilized to prepare nanoscale fibrous Co3O4 with improved physical and chemical properties for catalytic advanced oxidation applications

Verification of enzymes deterioration due to Cu(II) presence in an enhanced biological phosphorus removal system

This study experimentally demonstrated that polyphosphate accumulating organisms (PAOs) losing the abilities of anaerobically synthesizing polyhydroxyalkanoates and aerobically taking up phosphate under Cu(II) presence was due to the inhibition of enzyme activities of acetyl-CoA synthases (ACS) and polyphosphate kinase (PPK), respectively. ACS activity tests showed the apparent maximum specific activity (V_(max)) of ACS decreased with increasing Cu(II) concentration, revealing Cu(II) is a mixed inhibitor for ACS. Inhibition coefficients showed Cu(II) has a higher affinity for free ACS than for ACS-coenzyme A complex. PPK activity tests showed the V_(max) substantially decreased with increasing Cu(II) concentration, revealing Cu(II) is also a mixed inhibitor for PPK. Inhibition coefficients showed Cu(II) more easily bound to free PPK than to PPK-Adenosine triphosphate complex. Experimental data also showed the aerobic mechanism of PAOs taking up phosphate was completely interrupted when 3 mg L^(−1) of Cu(II) was added

Three-dimensional structure and cytokine distribution of platelet-rich fibrin

OBJECTIVES: Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1) can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. METHODS: Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg); it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. RESULTS: Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5) to low at the plasma end (p=0.19). Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. CONCLUSION: Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians

The RhoA-Rok-myosin II pathway is involved in extracellular matrix-mediated regulation of prolactin signaling in mammary epithelial cells

In mammary epithelial cells (MECs), prolactin-induced signaling and gene expression requires integrin-mediated cell adhesion to basement membrane (BM). In the absence of proper cell–BM interactions, for example, culturing cells on collagen-coated plastic dishes, signal propagation is substantially impaired. Here we demonstrate that the RhoA-Rok-myosin II pathway accounts for the ineffectiveness of prolactin signaling in MECs cultured on collagen I. Under these culture conditions, the RhoA pathway is activated, leading to downregulation of prolactin receptor expression and reduced prolactin signaling. Enforced activation of RhoA in MECs cultured on BM suppresses prolactin receptor levels, and prevents prolactin-induced Stat5 tyrosine phosphorylation and β-casein expression. Overexpression of dominant negative RhoA in MECs cultured on collagen I, or inhibiting Rok activity, increases prolactin receptor expression, and enhances prolactin signaling. In addition, inhibition of myosin II ATPase activity by blebbistatin also exerts a beneficial effect on prolactin receptor expression and prolactin signaling, suggesting that tension exerted by the collagen substratum, in collaboration with the RhoA-Rok-myosin II pathway, contributes to the failure of prolactin signaling. Furthermore, MECs cultured on laminin-coated plastic have similar morphology and response to prolactin as those cultured on collagen I. They display high levels of RhoA activity and are inefficient in prolactin signaling, stressing the importance of matrix stiffness in signal transduction. Our results reveal that RhoA has a central role in determining the fate decisions of MECs in response to cell–matrix interactions

Synthesis of a Bisbenzylideneacetone-Containing Benzoxazine and Its Photo- and Thermally Cured Thermoset

A bis­(4-hydroxybenzylidene)­acetone/aniline-based benzoxazine (<b>BHBA-a</b>) was prepared from a bisbenzylidene-containing bisphenol, bis­(4-hydroxybenzylidene)­acetone (<b>BHBA</b>), aniline, and paraformaldehyde through Mannich condensation in a cosolvent of toluene/ethanol (2:1, v/v). The structure of <b>BHBA-a</b> was successfully confirmed by Fourier transform infrared and ¹H and ¹³C NMR spectra. According to the differential scanning calorimetry (DSC) thermogram of <b>BHBA</b>, an immediate exothermic peak after the melting peak was observed, suggesting that <b>BHBA</b> is thermally active. NMR data of thermally treated <b>BHBA</b> confirm that the immediate exothermic peak after melting of <b>BHBA</b> in the DSC thermogram is resulted from the curing of a double bond. UV and ¹H NMR spectra of <b>BHBA-a</b> show that the bisbenzylideneacetone moiety underwent dimerization through the [2π + 2π] cycloaddition. Therefore, two procedures were applied to cure <b>BHBA-a</b>. The first one was thermal curing of the double bond of bisbenzylideneacetone and oxazine moieties. The second one was photocuring of the bisbenzylideneacetone moiety, followed by thermal curing of the oxazine moiety. The thermal properties of thermosets were evaluated based on these two procedures. Thermosets of <b>BHBA-a</b> exhibit <i>T</i>_g as high as 318 °C for curing procedure 1 and 342 °C for curing procedure 2. These values are much higher than that of a traditional bisphenol/aniline-based benzoxazine thermoset. We conclude that the thermal curing of the double bond of bisbenzylideneacetone and photodimerization of bisbenzylideneacetone contributes to the good thermal properties