PPAR-γ regulates the polarization of M2 macrophages to improve the microenvironment for autologous fat grafting.

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment.

Natural chlorophyll: a review of analysis methods, health benefits, and stabilization strategies.

Chlorophyll (Chl) is a natural pigment, widely distributed ranging from photosynthetic prokaryotes to higher plants, with an annual yield of up to 1.2 billion tons worldwide. Five types of Chls are observed in nature, that can be distinguished and identified using spectroscopy and mass spectrometry. Chl is also used in the food industry owing to its bioactivities, including obesity prevention, inflammation reduction, viral infection inhibition, anticancer effects, anti-oxidation, and immunostimulatory properties. It has great potential of being applied as a colorant and dietary supplement in the food industry. However, Chl is unstable under various enzymatic, acidic, heat, and light conditions, which limit its application. Although some strategies, such as aggregation with other food components, microencapsulation, and metal cation replacement, have been proposed to overcome these limitations, they are still not enough to facilitate its widespread application. Therefore, stabilization strategies and bioactivities of Chl need to be expected to expand its application in various fields, thereby aiding in the sustainable development of mankind.

Anatomical Study of the Superior Auricular Artery Using 3-Dimensional Computed Tomography Angiography.

BACKGROUND: The superior auricular artery (SAA)-retroauricular flap is commonly used for the repair of defects of the superior auricle. There are few studies about the anatomy of the SAA. OBJECTIVE: This study mainly analyzed the anatomical pattern of SAA. MATERIALS AND METHODS: Computed tomography (CT) was performed on 26 cadaver heads infused with lead oxide. The anatomical pattern of the SAA was statistically analyzed by 3-dimensional CT images. RESULTS: The SAA was classified into 3 types according to whether it gave off the helix branch or the auricular dorsal branch. The SAA was located mainly in an area 2 cm above and below the horizontal line at the midpoint of the 2 base points (the otobasion superius and the apex of the external auditory canal). The origin of each branch of the SAA was mainly located in Areas 2, 3, and 4 within a circular area that had the otobasion superius as the center of the circle and a radius of 2 cm. CONCLUSION: In this study, the 3 anatomical types and anatomical patterns of the SAA were identified. These findings can provide a reference for the design of SAA-retroauricular flaps and for surgical planning.

Evaluation of the Reproducibility of Auricular Subunit Markers Based on Three-Dimensional Computed Tomography.

BACKGROUND: As a facial feature, the auricle plays an important role in the integrity and aesthetics of the whole face. Auricular subunits are associated with patient satisfaction in auricular reconstruction, but there are few studies on auricular subunits. We want to evaluate the reproducibility of auricular subunits by measuring the coordinates of the marker points of auricular subunits, accordingly provide a reference for the improvement of auricular reconstruction and the aesthetics of auricular injection. METHODS: Mimics 19.0 was used to carry out three-dimensional (3D) reconstruction of the computed tomography (CT) scan data of patients' brains; measure the three-dimensional coordinates of the 13 auricular subunit markers, the morphological auricle length and width, and the physiological auricle length and width; and analyze the reproducibility as well as the differences between group. RESULTS: Reproducibility of auricle subunit markers: There are 1124 (58.82%) high reproducibility, 580 (30.35%) moderate reproducibility, and 207 (10.83%) low reproducibility. The superior tragus notch, tragus, and antitragus had the highest reproducibility. There was no significant difference between the groups in the marking points on the helix, and there were no statistically significant differences in the measurement values of the auricles on the two sides. The physiological ear length and width and the morphological ear length of males were larger than those of females. These showed significant differences between the age groups. CONCLUSION: Most auricular subunit markers have high reproducibility. The subunits with higher reproducibility are the structures that need to be optimized during auricle reconstruction surgery or auricle injection in the future. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Elderly Women Have a Higher Survival Rate of Grafted Donor Fat than Do Young Women Under the Influence of Low Estrogen Conditions.

BACKGROUND: Fat grafting is widely used in breast reconstruction and aesthetic plastic surgery. However, the success rate and effects of fat grafting, especially in elderly female donors, are observed. This study aimed to explore the difference in the survival rate of donor fat from elderly women and young women in fat grafting. METHODS: We collected adipose tissue samples from two healthy Chinese women: a young woman and an elderly woman. In addition, adipose tissue samples were collected from female nude mice in four experimental groups-CON-Y, CON-O, OVX-Y, and OVX-O-after fat transplantation. Grafts were harvested, weighed, and subjected to assessment of histology and angiogenesis. RESULTS: An ovariectomy model was successfully established to validate the effect of low estrogen levels on fat grafting results. Due to the influence of low estrogen levels, the graft survival rate of donor site fat was significantly higher in elderly women than in young women, accompanied by a lesser degree of angiogenesis. Low estrogen levels led to adipocyte hypertrophy, which may be related to decreased AQP-7 expression. CONCLUSIONS: AQP-7 downregulation due to low estrogen levels induces adipocyte hypertrophy, and donor fat from elderly women exhibits a higher survival rate after fat transplantation. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Exosomes Derived from Human Adipose-Derived Stem Cells Cannot Distinctively Promote Graft Survival in Cryopreservation Fat Grafting.

BACKGROUND: Cryopreserved fat has limited clinical applications due to its rapid absorption, high degree of fibrosis, and risk of complications after grafting. Many studies have verified that Adipose-derived mesenchymal stem cell-derived exosomes (ADSC-Exos) can improve fresh fat graft survival. This study assessed whether ADSC-Exos could improve the survival of cryopreserved fat grafts. METHODS: Exosomes were isolated from human ADSCs were subcutaneously engrafted with adipose tissues stored under different conditions (fresh; cryopreserved for 1 month) into the backs of BALB/c nude mice (n = 24), and exosomes or PBS were administered weekly. Grafts were harvested at 1, 2, 4, and 8 weeks, and fat retention rate, histologic, and immunohistochemical analyses were conducted. RESULTS: At 1, 2, and 4 weeks after the transfer, cryopreserved fat grafts in groups of exosome-treated showed better fat integrity, fewer oil cysts, and reduced fibrosis. Further investigations of macrophage infiltration and neovascularization revealed that those exosomes increased the number of M2 macrophages at 2 and 4 weeks (p<0.05), but had limited impact on vascularization (p>0.05). It's important to note that no significant differences (p>0.05) were observed between the two groups in both histological and immunohistochemical evaluations at 8 weeks post-transplantation. CONCLUSIONS: This study suggests that ADSC-Exos could improve the survival of cryopreserved fat grafts in the short term (within 4 weeks), but the overall improvement was poor (after 8 weeks). This suggests that the utility of using ADSC-Exos to treat cryopreserved adipose tissue grafts is limited. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Positions of the Glabellar Arteries: Implications for Glabellar Injection.

BACKGROUND: Glabellar filler injection is linked to an increased risk of blindness. A thorough understanding of vascular changes in the glabellar area is critical for safety. The study's goal was to precisely determine the three-dimensional placements of the arteries in the glabellar area. METHODS: In 117 cadavers, the vascular structures in the glabellar area were examined. There were four segments (S1/S1'-S4/S4') and five points (P1-P5) specified. The number of identified arteries found in each section and at each position was tallied. Additionally, the depth of the underlying identified artery under each site was measured. RESULTS: One to three named arteries per glabellar segment were found. Each segment had at least one named artery, and the number of named arteries detected between S1/S1' and S4/S4' decreased. The chance of encountering identified arteries at the 5 designated locations, P1-P5, was 7/117 (6.0%), 6/117 (5.1%), 7/117 (6.0%), 6/117 (5.1%), and 16/117 (13.7%), respectively. At P1-P5, the major artery trunk was 1.8 ± 0.3 mm, 1.6 ± 0.3 mm, 1.4 ± 0.2 mm, 1.3 ± 0.3 mm, and 1.1 ± 0.2 mm below the skin. CONCLUSIONS: The site of the glabellar arteries was clearly shown in this investigation; these arteries were met at a rate of 14% from P1 to P5. We demonstrated that a single entry site through the glabella via cannula could readily keep the needle deep enough for safe glabellar filler injection. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Inhibition of HDAC1 alleviates monocrotaline-induced pulmonary arterial remodeling through up-regulation of miR-34a.

BACKGROUND: It has been found that up-regulation of histone deacetylases 1 (HDAC1) is involved in the development of pulmonary arterial hypertension (PAH). However, it is still unclear whether inhibition of HDAC1 suppresses the development of PAH via restoring miR-34a level in monocrotaline (MCT)-induced PAH rats. METHODS: PAH rat models were induced by intraperitoneal injection of MCT. HDAC1 was suppressed by intraperitoneal injection of the class I HDAC inhibitor MS-275, and miR-34a was over-expressed via tail vein injection of miR-34a agomiR. RESULTS: HDAC1 protein was significantly increased in MCT-induced PAH rats; this was accompanied with down-regulation of miR-34a and subsequent up-regulation of matrix metalloproteinase 9 (MMP-9)/tissue inhibitor of metalloproteinase 1 (TIMP-1) and MMP-2/TIMP-2. Administration of PAH rats with MS-275 or miR-34a agomiR dramatically abolished MCT-induced reduction of miR-34a and subsequent up-regulation of MMP-9/TIMP-1 and MMP-2/TIMP-2, finally reduced extracellular matrix (ECM) accumulation, pulmonary arterial remodeling, right ventricular systolic pressure (RVSP) and right ventricle hypertrophy index (RVHI) in PAH rats. CONCLUSIONS: HDAC1 contributes to the development of MCT-induced rat PAH by suppressing miR-34a level and subsequently up-regulating the ratio of MMP-9/TIMP-1 and MMP-2/TIMP-2. Inhibition of HDAC1 alleviates pulmonary arterial remodeling and PAH through up-regulation of miR-34a level and subsequent reduction of MMP-9/TIMP-1 and MMP-2/TIMP-2, suggesting that inhibition of HDAC1 might have potential value in the management of PAH.

Microenvironmental Changes in the Surviving Fat 1 Year After Autologous Fat Transplantation for Breast Augmentation.

BACKGROUND: Autologous fat is currently one of the most commonly used soft tissue materials in plastic surgery, but the changes that occur in fat after transplantation are unclear. Existing studies on the changes in surviving fat mostly involve animal experiments. OBJECTIVES: The aim of this study was to obtain surviving fat 1 year after clinical autologous fat transplantation for breast augmentation, to explain the microenvironmental changes after fat transplantation from a clinical perspective, and to verify previous research conclusions, thus providing new insight into fat survival. METHODS: Samples of surviving fat were obtained from 5 patients 1 year after they had undergone autologous fat transplantation for breast augmentation, and normal fat samples were obtained from 5 patients who had not undergone this procedure. The differences between CD68 and CD31 were analyzed immunohistochemically, and between CD34 and Ki67 by immunofluorescence. We also tested whether UCP-1 is expressed in surviving fat. RESULTS: The relative CD68, CD34, and Ki67 expression levels in the surviving fat tissue were significantly higher than those in the normal fat tissue (PCD68 = 0.04, PCD34 = 0.03, PKi67 = 0.02). The relative CD31 expression was not significantly different between the two groups (P = 0.52). No UCP-1 expression was observed in any surviving fat tissue. CONCLUSIONS: Chronic inflammatory reactions mediated by macrophages were detectable 1 year after autologous fat transplantation for breast augmentation. The mesenchymal stem cell content in surviving fat was higher than that in normal fat, but the number of blood vessels was close to that in normal breast fat tissue. No genesis of brown fat was found.

The Effect of Previous Irradiation for Patients With Prosthetic Breast Reconstruction: A Meta-Analysis.

BACKGROUND: Results regarding immediate prosthetic breast reconstruction after postmastectomy radiation therapy (PMRT) have been inconsistent. OBJECTIVES: The authors aimed to assess the efficacy and safety of PMRT before immediate prosthetic breast reconstruction for patients with breast cancer. METHODS: Electronic databases (PubMed, EmBase, and the Cochrane Library) were systematically searched to identify eligible studies from their inception until March 2020. The pooled odds ratio (OR) with 95% confidence intervals (CIs) was applied as an effect estimate and calculated using the random-effects model. RESULTS: Nineteen studies including a total of 6757 patients were selected for final meta-analysis. The pooled OR showed that PMRT was associated with a higher incidence of reconstruction failure (OR = 2.57; 95% CI =1.55-4.26; P < 0.001), capsular contracture (OR = 5.99; 95% CI = 3.12-11.47; P < 0.001), and overall complications (OR = 2.52; 95% CI = 1.68-3.79; P < 0.001). It was also associated with a lower incidence of patient satisfaction (OR = 0.29; 95% CI = 0.16-0.52; P < 0.001) and good aesthetic results (OR = 0.25; 95% CI = 0.12-0.52; P < 0.001) compared with those who did not undergo PMRT. These significant associations could be affected by study design, mean age, stage of immediate breast reconstruction, follow-up, and study quality. CONCLUSIONS: Although PMRT is the standard adjuvant therapy for mastectomy patients treated with immediate implant-based breast reconstruction, PMRT for patients undergoing immediate implant-based breast reconstruction has been associated with high risks of reconstruction failure, capsular contracture, and overall complications as well as low incidences of patient satisfaction and good aesthetic results.

Additional common loci associated with stroke and obesity identified using pleiotropic analytical approach.

Stroke is a complex disease with multiple etiologies. Numerous studies suggest an established association between obesity and stroke, which may partly arise from the shared genetic components between the two phenotypes. Despite genome-wide association studies (GWASs) have identified some loci associated with stroke and obesity individually, the estimated genetic variability explained by these loci is limited (especially for stroke) and the pleiotropic loci between them are largely unknown. In this study, we jointly applied the pleiotropy-informed conditional false discovery rate (cFDR) method and the genetic analysis incorporating pleiotropy and annotation (GPA) method on summary statistics of two large GWASs to detect the genetic overlap between stroke (n = 446,696) and obesity (n = 681,275). Stratified Q-Q and fold-enrichment plots showed strong pleiotropic enrichment between the two phenotypes. With cFDR < 0.05 and fdr.GPA < 0.2, we identified 24 (16 novel) stroke-associated SNPs and 12 (10 novel) of them to be potentially pleiotropic SNPs for both phenotypes. The corresponding genes were enriched in trait-associated gene ontology (GO) terms "brain development" and "negative regulation of transport". In conclusion, our study demonstrated the feasibility and effectivity of the two pleiotropic methods which successfully improved the genetic discovery by incorporating related GWAS datasets and validated the genetic intercommunity between stroke and obesity. The identification of pleiotropic loci may provide us any new insights into potential genetic and etiology mechanism between them for the further studies.

Three-Dimensional Analysis of Age-Related Orbital and Midfacial Bone Remodeling in Asians.

BACKGROUND: Facial bony changes vary among races, yet few studies have been conducted in Asians. OBJECTIVE: To analyze the aging of orbital and midfacial bones in Asians. METHODS: Based on the two-dimensional data obtained from the computed tomography scanner of imaging department, 3D reconstructions were conducted to take measurements (orbital diagonal diameter, orbital width, orbital area, maxillary angle, midfacial height, pyriform angle, pyriform width, and pyriform area). RESULTS: In this retrospective study of 261 subjects, a significant decrease in the orbital diagonal diameter, orbital width, and midfacial height was found in men, whereas women displayed a significant increase in the pyriform width and a significant decrease in maxillary angle and midfacial height by three-dimensional analysis. CONCLUSION: This study verifies the minor female changes in the orbital region and less dramatic male changes in the midfacial region compared with that in Caucasians. Individualized treatment should be performed according to different genders and races. Further exploration of facial bone metabolism may have valuable implications for Asians.

COP9 signalosome subunit 6 mediates PDGF -induced pulmonary arterial smooth muscle cells proliferation.

Up-regulation of mammalian COP9 signalosome subunit 6 (CSN6) and consequent reduction of SCF ubiquitin ligase substrate receptor ß-transduction repeat-containing protein (ß-TrCP) have been shown to be associated with cancer cells proliferation. However, it is unclear whether CSN6 and ß-TrCP are also involved in PDGF-induced pulmonary arterial smooth muscle cells (PASMCs) proliferation. This study aims to address this issue and further explore its potential mechanisms. Our results indicated that PDGF phosphorylated Akt, stimulated PASMCs proliferation; while inhibition of PDGF receptor (PDGFR) by imatinib prevented these effects. PDGF further up-regulated CSN6 protein expression, this was accompanied with ß-TrCP reduction and increase of Cdc25A. Inhibition of PDGFR/PI3K/Akt signaling pathway reversed PDGF-induced such changes and cell proliferation. Prior transfection of CSN6 siRNA blocked PDGF-induced ß-TrCP down-regulation, Cdc25A up-regulation and cell proliferation. Furthermore, pre-treatment of cells with MG-132 also abolished PDGF-induced ß-TrCP reduction, Cdc25A elevation and cell proliferation. In addition, pre-depletion of Cdc25A by siRNA transfection suppressed PDGF-induced PASMCs proliferation. Taken together, our study indicates that up-regulation of CSN6 by PDGFR/PI3K/Akt signaling pathway decreases ß-TrCP by increasing its ubiquitinated degradation, and thereby increases the expression of Cdc25A, which promotes PDGF-induced PASMCs proliferation.

Serum Surfactant Protein D is a Potential Biomarker for Chronic Obstructive Pulmonary Disease: a Systematic Review and Meta-analysis.

BACKGROUND: A number of studies have been conducted to investigate the association between serum surfactant protein D (SP-D) concentration and chronic obstructive pulmonary disease (COPD) risk. However, the results are inconsistent. This systematic review and meta-analysis aim to investigate whether serum SP-D concentration is a potential biomarker for COPD diagnosis. METHODS: We searched Web of Science, PubMed, China National Knowledge Infrastructure (CNKI), and Wanfang Database from inception through July 18, 2018. The standardized mean difference (SMD) with 95% confidence interval (CI) was used to investigate the effect sizes. RESULTS: Seventeen eligible studies from a total of 4,639 subjects were finally included in this systematic review and meta-analysis. The results indicated that serum SP-D levels in COPD patients were significantly higher than those in controls (SMD = 1.01, 95% CI = 0.62 - 1.41, p < 0.001). We also found that serum SP-D concentration in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients was significantly higher than that in stable COPD patients (SMD = 1.50, 95% CI = 0.92 - 2.08, p < 0.001), and serum SP-D concentration was higher in smokers than in nonsmokers in healthy population (SMD = 1.50, 95% CI = 0.35 - 2.64, p = 0.025). CONCLUSIONS: The current systematic review and meta-analysis indicates that serum SP-D levels may be a promising biomarker for COPD. In particular, increased serum SP-D levels appear to be associated with acute exacerbation of COPD and smoking in healthy population.

Optimal Use Ratio of the Stromal Vascular Fraction (SVF): An Animal Experiment Based on Micro-CT Dynamic Detection After Large-Volume Fat Grafting.

BACKGROUND: The addition of the stromal vascular fraction (SVF) can enhance the postoperative survival rate of fat. However, a universal SVF application method is currently unavailable. Therefore, a simple and convenient guideline for SVF addition is needed for its clinical application. OBJECTIVES: The authors sought to evaluate whether SVF can improve fat survival after large-volume fat grafting and to find a simple and convenient standard for the clinical use of SVF. METHODS: Patient fat samples were obtained after liposuction for SVF preparation and grafting. Four types of grafts were prepared with different SVF ratios: 0:1, 1:1, 2:1, and 4:1 SVF:fat. After intensive mixing, fat grafts (5 mL) were randomly injected into both sides of the backs of athymic rats (n = 15). At 24 hours and 1, 3, 6, and 9 months after the operation, microcomputed tomography scanning was performed to calculate the fat survival rate. RESULTS: Nine months after the operation, the survival rates of fat in the 4 groups were 8.89 ± 1.62% (0:1), 18.26 ± 3.85% (1:1), 8.83 ± 1.46% (2:1), and 7.96 ± 1.31% (4:1). The 1:1 group exhibited the greatest survival rate (P < 0.01), and the adipose tissue histological patterns and blood vessel quality were enhanced compared with those in the other groups. CONCLUSIONS: An appropriate SVF ratio can increase the fat survival rate after large-volume fat grafting, but no linear relationship exists between the SVF ratio and fat survival. The optimal SVF:fat ratio for grafting is 1:1.

SphK1/S1P Mediates PDGF-Induced Pulmonary Arterial Smooth Muscle Cell Proliferation via miR-21/BMPRII/Id1 Signaling Pathway.

BACKGROUND/AIMS: The underlying molecular mechanisms involved in sphingosine kinase 1 (SphK1)/sphingosine 1-phosphate (S1P) mediation of platelet-derived growth factor (PDGF)-induced pulmonary arterial smooth muscle cell (PASMC) proliferation are still unclear, and the present study aims to address this issue. METHODS: Small interfering RNA (siRNA) and microRNA inhibitor transfection was performed to block the expression of SphK1, bone morphogenetic protein receptor II (BMPRII) and microRNA-21 (miR-21). Gene expression levels of SphK1, BMPRII and inhibitor of DNA binding 1 (Id1) were detected by immunoblotting, miR-21 expression level was examined with qRT-PCR, and S1P production was measured by ELISA. Additionally, PASMC proliferation was determined by BrdU incorporation assay. RESULTS: Our results indicated that PDGF increased the expression of SphK1 protein and S1P production, up-regulated miR-21 expression, reduced BMPRII and Id1 expression, and promoted PASMCs proliferation. Pre-silencing of SphK1 with siRNA reversed PDGF-induced S1P production, miR-21 up-regulation, BMPRII and Id1 down-regulation, as well as PASMC proliferation. Pre-inhibition of miR-21 also blocked BMPRII and Id1 down-regulation as well as PASMC proliferation caused by PDGF. Knockdown of BMPRII down-regulated Id1 expression in PASMCs. We further found that inhibition of PI3K/Akt and ERK signaling pathways, particularly ERK cascade, suppressed PDGF-induced above changes. CONCLUSION: Our study indicates that SphK1/S1P pathway plays an important role in PDGF-induced PASMC proliferation via miR-21/BMPRII/Id1 axis and targeting against SphK1/S1P axis might be a novel strategy in the prevention and treatment of pulmonary arterial hypertension (PAH).

Outage-Based Resource Allocation for DF Two-Way Relay Networks with Energy Harvesting.

A joint resource allocation algorithm to minimize the system outage probability is proposed for a decode-and-forward (DF) two-way relay network with simultaneous wireless information and power transfer (SWIPT) under a total power constraint. In this network, the two sources nodes exchange information with the help of a passive relay, which is assumed to help the two source nodes' communication without consuming its own energy by exploiting an energy-harvesting protocol, the power splitting (PS) protocol. An optimization framework to jointly optimize power allocation (PA) at the source nodes and PS at the relay is developed. Since the formulated joint optimization problem is non-convex, the solution is developed in two steps. First, the conditionally optimal PS ratio at the relay node for a given PA ratio is explored; then, the closed-form of the optimal PA in the sense of minimizing the system outage probability with instantaneous channel state information (CSI) is derived. Analysis shows that the optimal design depends on the channel condition and the rate threshold. Simulation results are obtained to validate the analytical results. Comparison with three existing schemes shows that the proposed optimized scheme has the minimum system outage probability.

Interleukin-12B gene polymorphisms and bronchial asthma risk: A meta-analysis.

OBJECTIVE: This meta-analysis aims to investigate whether interleukin-12B (IL-12B) -1188A/C or the promoter polymorphisms may be a risk factor for asthma. DATA SOURCES: Web of Science, PubMed, China National Knowledge Infrastructure (CNKI) and Wanfang databases were searched (updated August 20, 2015). STUDY SELECTIONS: Articles evaluating the association between IL-12B genetic polymorphisms and asthma risk were selected. RESULTS: 13 eligible studies with a total of 5092 subjects were finally included in this meta-analysis. For IL-12B -1188A/C, analysis by ethnicity indicated that there was a markedly reduced risk for asthma in East Asian (CC + AC vs. AA: OR = 0.64, 95% CI = 0.50-0.81, P < 0.001). For IL-12B promoter, analysis by ethnicity indicated there was a markedly increased risk in East Asian (MM vs. WM + WW: OR = 1.57, 95% CI = 1.18-2.10, P = 0.002). Analysis by allergic state revealed the similar results in atopic subgroup. CONCLUSIONS: IL-12B -1188 C allele may be a protective factor against asthma in East Asian. In addition, promoter MM genotype may be a risk factor for asthma in East Asian and allergic people.

Wireless Energy Harvesting Two-Way Relay Networks with Hardware Impairments.

This paper considers a wireless energy harvesting two-way relay (TWR) network where the relay has energy-harvesting abilities and the effects of practical hardware impairments are taken into consideration. In particular, power splitting (PS) receiver is adopted at relay to harvests the power it needs for relaying the information between the source nodes from the signals transmitted by the source nodes, and hardware impairments is assumed suffered by each node. We analyze the effect of hardware impairments [-20]on both decode-and-forward (DF) relaying and amplify-and-forward (AF) relaying networks. By utilizing the obtained new expressions of signal-to-noise-plus-distortion ratios, the exact analytical expressions of the achievable sum rate and ergodic capacities for both DF and AF relaying protocols are derived. Additionally, the optimal power splitting (OPS) ratio that maximizes the instantaneous achievable sum rate is formulated and solved for both protocols. The performances of DF and AF protocols are evaluated via numerical results, which also show the effects of various network parameters on the system performance and on the OPS ratio design.

Knockdown of AMPKα2 Promotes Pulmonary Arterial Smooth Muscle Cells Proliferation via mTOR/Skp2/p27(Kip1) Signaling Pathway.

It has been shown that activation of adenosine monophosphate-activated protein kinase (AMPK) suppresses proliferation of a variety of tumor cells as well as nonmalignant cells. In this study, we used post-transcriptional gene silencing with small interfering RNA (siRNA) to specifically examine the effect of AMPK on pulmonary arterial smooth muscle cells (PASMCs) proliferation and to further elucidate its underlying molecular mechanisms. Our results showed that knockdown of AMPKα2 promoted primary cultured PASMCs proliferation; this was accompanied with the elevation of phosphorylation of mammalian target of rapamycin (mTOR) and S-phase kinase-associated protein 2 (Skp2) protein level and reduction of p27(Kip1). Importantly, prior silencing of mTOR with siRNA abolished AMPKα2 knockdown-induced Skp2 upregulation, p27(Kip1) reduction as well as PASMCs proliferation. Furthermore, pre-depletion of Skp2 by siRNA also eliminated p27(Kip1) downregulation and PASMCs proliferation caused by AMPKα2 knockdown. Taken together, our study indicates that AMPKα2 isoform plays an important role in regulation of PASMCs proliferation by modulating mTOR/Skp2/p27(Kip1) axis, and suggests that activation of AMPKα2 might have potential value in the prevention and treatment of pulmonary arterial hypertension.