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Urban parks play a crucial role in urban public green infrastructure, providing recreational places for urban residents while carrying values of aesthetics, ecology, humanities, economy, life, and society. However, achieving an equitable and efficient spatial layout of urban parks is a challenging task due to limited urban space resources, which requires further exploration. This study employed multisource big data and GIS technology to constructed an indicator system for evaluating the equity-efficiency of urban park spatial distribution. We examined the spatial distribution of 85 parks across 62 sub-districts in the main urban area of Chengdu, the largest city in western China and the first Park City of China. The results demonstrated that equity was polarized, with an indicator value ranging from 0 to 0.77 and an average value of 0.32. The sub-district of Sansheng had the highest equity, while Wenjia and Kanghe had the lowest equity. Twenty-one sub-districts had no parks, and the equity of park spatial distribution in these areas was low. The efficiency indicator ranged from 0.20 to 0.62, with an average value of 0.40. The efficiency of the main urban area was high in the southwest and low in the northeast. The sub-district of Huangtianba had the highest efficiency, while Jinguanyi had the lowest efficiency. In the two-dimensional quadrant of equity-efficiency, 24 sub-districts had high equity and high efficiency, 13 sub-districts had high equity and low efficiency, 4 sub-districts had low equity and high efficiency, and 21 sub-districts had low equity and low efficiency. At the district level, only Chenghua District's park was spatial equitable and efficient, surpassing the average level of the main urban area. Finally, we discussed the findings in the context of planning policies for Chengdu in recent years. We proposed that strengthening the construction of small urban parks and green spaces, improving park facilities to meet the diverse social needs of people, and enhancing the quality and attractiveness of the parks are crucial for the future development of park green spaces in the main urban areas of Chengdu. [ABSTRACT FROM AUTHOR]

A critical challenge in tissue regeneration is to develop constructs that effectively integrate with the host tissue. Here, we describe a composite, laser micromachined, collagen–alginate construct containing human mesenchymal stem cells (hMSCs) for tissue repair applications. Collagen type I was fashioned into laminated collagen sheets to form a mechanically robust fascia that was subsequently laser micropatterned with pores of defined dimension and spatial distribution as a means to modulate mechanical behavior and promote tissue integration. Significantly, laser micromachined patterned constructs displayed both substantially greater compliance and suture retention strength than non-patterned constructs. hMSCs were loaded in an RGD-functionalized alginate gel modified to degrade in vivo . Over a 7 day observation period in vitro , high cell viability was observed with constant levels of VEGF, PDGF-β and MCP-1 protein expression. In a full thickness abdominal wall defect model, the composite construct prevented hernia recurrence in Wistar rats over an 8-week period with de novo tissue and vascular network formation and the absence of adhesions to underlying abdominal viscera. As compared to acellular constructs, constructs containing hMSCs displayed greater integration strength (cell seeded: 0.92 ± 0.19 N/mm vs. acellular: 0.59 ± 0.25 N/mm, p = 0.01), increased vascularization (cell seeded: 2.7–2.1/hpf vs. acellular: 1.7–2.1/hpf, p < 0.03), and increased infiltration of macrophages (cell seeded: 2021–3630 μm 2 /hpf vs. acellular: 1570–2530 μm 2 /hpf, p < 0.05). A decrease in the ratio of M1 macrophages to total macrophages was also observed in hMSC-populated samples. Laser micromachined collagen–alginate composites containing hMSCs can be used to bridge soft tissue defects with the capacity for enhanced tissue repair and integration. Statement of Significance Effective restoration of large soft tissue defects caused by trauma or treatment complications represents a critical challenge in the clinic. In this study, a novel composite construct was engineered and evaluated for stem cell delivery and tissue repair. Laser micromachining was used to fabricate patterned, microporous constructs designed with pores of defined size and distribution as a means to tune mechanical responses, accommodate and protect incorporated cells, and enhance tissue integration. The construct was embedded within an engineered alginate gel containing hMSCs. Upon repair of a full thickness abdominal wall defect in a rat model, the composite construct modulated host innate immunity towards a reparative phenotypic response, promoted neovascularization and associated matrix production, and increased the strength of tissue integration. [ABSTRACT FROM AUTHOR]

Tissue-engineered vascular grafts require long fabrication times, in part due to the requirement of cells from a variety of cell sources to produce a robust, load-bearing extracellular matrix. Herein, we propose a design strategy for the fabrication of tubular conduits comprising collagen fiber networks and elastin-like protein polymers to mimic native tissue structure and function. Dense fibrillar collagen networks exhibited an ultimate tensile strength (UTS) of 0.71±0.06MPa, strain to failure of 37.1±2.2% and Young’s modulus of 2.09±0.42MPa, comparing favorably to a UTS and a Young’s modulus for native blood vessels of 1.4–11.1MPa and 1.5±0.3MPa, respectively. Resilience, a measure of recovered energy during unloading of matrices, demonstrated that 58.9±4.4% of the energy was recovered during loading–unloading cycles. Rapid fabrication of multilayer tubular conduits with maintenance of native collagen ultrastructure was achieved with internal diameters ranging between 1 and 4mm. Compliance and burst pressures exceeded 2.7±0.3%/100mmHg and 830±131mmHg, respectively, with a significant reduction in observed platelet adherence as compared to expanded polytetrafluoroethylene (ePTFE; 6.8±0.05×105 vs. 62±0.05×105 platelets mm–2, p <0.01). Using a rat aortic interposition model, early in vivo responses were evaluated at 2weeks via Doppler ultrasound and CT angiography with immunohistochemistry confirming a limited early inflammatory response (n =8). Engineered collagen–elastin composites represent a promising strategy for fabricating synthetic tissues with defined extracellular matrix content, composition and architecture. [ABSTRACT FROM AUTHOR]

Abstract: Chemokines are important for activation of a host of cellular immune and inflammatory responses including cell signaling, activation, and communication. M‐T7, a myxoma virus protein, inhibits the activity of chemokines by direct binding to chemokines and/or with glycosaminoglycans (GAGs). To study the effects of this chemokine‐modulating protein (CMP), we use a variety of in vitro and in vivo techniques to evaluate M‐T7 inhibition of inflammatory cells. To quickly analyze the effects of M‐T7, changes in cell adhesion and membrane fluidity are measured as well as cell migration in mouse ascites. For more physiological analyses, an aortic transplant model in rodents is used to assess change in inflammatory cell infiltrates and vascular plaque growth (rejection). Utilization of the combination of these in vitro and in vivo techniques allows for a more complete study of the chemokine‐modulating activity of M‐T7, and can be used to study other immune and inflammation‐modulating proteins. [Copyright &y& Elsevier]

The thrombolytic serine protease cascade is intricately involved in activation of innate immune responses. The urokinase-type plasminogen activator and receptor form complexes that aid inflammatory cell invasion at sites of arterial injury. Plasminogen activator inhibitor-1 is a mammalian serpin that binds and regulates the urokinase receptor complex. Serp-1, a myxomaviral serpin, also targets the urokinase receptor, displaying profound anti-inflammatory and anti-atherogenic activity in a wide range of animal models. Serp-1 reactive center site mutations, mimicking known mammalian and viral serpins, were constructed in order to define sequences responsible for regulation of inflammation. Thrombosis, inflammation, and plaque growth were assessed after treatment with Serp-1, Serp-1 chimeras, plasminogen activator inhibitor-1, or unrelated viral serpins in plasminogen activator inhibitor or urokinase receptor-deficient mouse aortic transplants. Altering the P1-P1′ Arg-Asn sequence compromised Serp-1 protease-inhibitory activity and anti-inflammatory activity in animal models; P1-P1′ Ala-Ala mutants were inactive, P1 Met increased remodeling, and P1′ Thr increased thrombosis. Substitution of Serp-1 P2–P7 with Ala6 allowed for inhibition of urokinase but lost plasmin inhibition, unexpectedly inducing a diametrically opposed, proinflammatory response with mononuclear cell activation, thrombosis, and aneurysm formation (p < 0.03). Other serpins did not reproduce Serp-1 activity; plasminogen activator inhibitor-1 increased thrombosis (p < 0.0001), and unrelated viral serpin, CrmA, increased inflammation. Deficiency of urokinase receptor in mouse transplants blocked Serp-1 and chimera activity, in some cases increasing inflammation. In summary, 1) Serp-1 anti-inflammatory activity is highly dependent upon the reactive center loop sequence, and 2) plasmin inhibition is central to anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

Discusses a study on the role of Serp-1, a viral anti-inflammatory serpin, in regulating cellular serine proteinase and serpin responses to vascular injury. Ability of serp-1 in protecting virus-infected tissues from host inflammatory responses; Mechanisms of viral serpin inhibition of vascular inflammatory responses; Treatment of endothelial cells with antibody to urokinase-type plasminogen activator.

Abstract: Aneurysms remain a significant medical problem and our current understanding of aneurysm formation and developmental stages remains incomplete. Noninvasive 3-D micro-ultrasound (3-D micro-US) imaging technologies designed for noninvasive evaluation of small laboratory animals diminish risks associated with invasive examination and provide in-situ (live) analysis of vascular morphological changes, which enables quantitative measurements of live biological specimens. We demonstrate here that aneurysm morphology can be quantified using 3-D micro-US, and we validate this methodology through comparison of geometric measures with those obtained from 3-D serial histologic records in a mouse model of accelerated aneurysm formation. Aneurysms were induced in Balb/C mice after C57Bl/6 mouse aortic transplant with injections of a pro-inflammatory viral serpin with a mutated reactive site. Aortic transplant segments were imaged 28 days after transplant using 3-D micro-US. Upon sacrifice, the aortas were excised and histology sections (5-μm thick) were digitized, co-registered using mutual information and stacked to form 3-D images. Surfaces of the mouse aorta and aneurysm were manually segmented from the 3-D micro-US and histology images. Comparisons with 3-D histology images demonstrated that 3-D micro-US allowed in-vivo analysis of aneurysm morphology, including total aneurysm area, plaque growth and lumen size. Linear regression of 3-D US-derived aneurysm and plaque volumes vs. 3-D histology-derived volumes resulted in slopes of 1.30 (R 2 = 0.96) and 1.20 (R 2 = 0.98), respectively, demonstrating that 3-D micro-US measurements can be used to track aneurysm growth in a mouse aortic transplant model. (E-mail: afenster@imaging.robarts.ca) [Copyright &y& Elsevier]

Objectives: To evaluate the effect of learning curve on supine mini-percutaneous nephrolithotomy (PNL) outcomes.Methods: The aim of the study was to include a total of 75 patients. All of the patients were operated on by the same team, which had experience of at least 100 prone mini-PNL cases. The team was led by a surgeon who had observed 40 supine conventional PNL procedures (sheath size 24 Fr) over a period of 3 months at an endourology center with experience in supine PNL and surgeries were performed by the same primary surgeon. Patients were divided equally into 5 groups, as first 15 cases in Group 1, and final 15 in Group 5. Groups were compared according to preoperative characteristic, intraoperative result, complication rate, and success rate.Results: The mean access time was 14 minutes in group 1. It decreased to mean of 10.3 minutes for cases 31 through 45, and afterward significant decrease occurred up to a mean of 6.5 minutes for cases 61 through 75 (P ≤.001). According to the Clavien-Dindo classification system, complications were assessed, and a decrease was observed from group 1 to group 5 (40%, 20%, 26.6%, 6.7%, and 13.3%, respectively). The stone free rate increased from the mean of 66.7% for the first two groups to 80% for group 3 and increase up to the 93.3% for group 4 and 5 (P = .128).Conclusion: The present study showed that considering the decrease in access time and operation time 60 patients could be enough for surgical competency as well as the complications and stone-free rates reached satisfactory levels after 45 patients. [ABSTRACT FROM AUTHOR]

Virtually all biomaterials are susceptible to biofilm formation and, as a consequence, device-associated infection. The concept of an immobilized liquid surface, termed slippery liquid-infused porous surfaces (SLIPS), represents a new framework for creating a stable, dynamic, omniphobic surface that displays ultralow adhesion and limits bacterial biofilm formation. A widely used biomaterial in clinical care, expanded polytetrafluoroethylene (ePTFE), infused with various perfluorocarbon liquids generated SLIPS surfaces that exhibited a 99% reduction in S . aureus adhesion with preservation of macrophage viability, phagocytosis, and bactericidal function. Notably, SLIPS modification of ePTFE prevents device infection after S . aureus challenge in vivo, while eliciting a significantly attenuated innate immune response. SLIPS-modified implants also decrease macrophage inflammatory cytokine expression in vitro, which likely contributed to the presence of a thinner fibrous capsule in the absence of bacterial challenge. SLIPS is an easily implementable technology that provides a promising approach to substantially reduce the risk of device infection and associated patient morbidity, as well as health care costs. [ABSTRACT FROM AUTHOR]

Serpins regulate coagulation and inflammation, binding serine proteases in suicide-inhibitory complexes. Target proteases cleave the serpin reactive center loop scissile P1-P1' bond, resulting in serpin-protease suicide-inhibitory complexes. This inhibition requires a near full-length serpin sequence. Myxomavirus Serp-1 inhibits thrombolytic and thrombotic proteases, whereas mammalian neuroserpin (NSP) inhibits only thrombolytic proteases. Both serpins markedly reduce arterial inflammation and plaque in rodent models after single dose infusion. In contrast, Serp-1 but not NSP improves survival in a lethal murine gammaherpesvirus68 (MHV68) infection in interferon γ-receptor-deficient mice (IFNγR-/-). Serp-1 has also been successfully tested in a Phase 2a clinical trial. We postulated that proteolytic cleavage of the reactive center loop produces active peptide derivatives with expanded function. Eight peptides encompassing predicted protease cleavage sites for Serp-1 and NSP were synthesized and tested for inhibitory function in vitro and in vivo. In engrafted aorta, selected peptides containing Arg or Arg-Asn, not Arg-Met, with a 0 or -1 charge, significantly reduced plaque. Conversely, S-6 a hydrophobic peptide of NSP, lacking Arg or Arg-Asn with -4 charge, induced early thrombosis and mortality. S-1 and S-6 also significantly reduced CD11b+ monocyte counts in mouse splenocytes. S-1 peptide had increased efficacy in plasminogen activator inhibitor-1 serpin-deficient transplants. Plaque reduction correlated with mononuclear cell activation. In a separate study, Serp-1 peptide S-7 improved survival in the MHV68 vasculitis model, whereas an inverse S-7 peptide was inactive. Reactive center peptides derived from Serp-1 and NSP with suitable charge and hydrophobicity have the potential to extend immunomodulatory functions of serpins. [ABSTRACT FROM AUTHOR]

Objective To evaluate the outcomes of kidney stone treatment using flexible ureterorenoscopy (f-URS) among patients with chronic kidney disease (CKD). Patients and Methods Data of patients who underwent f-URS between January 2009 and December 2012 were collected. Patients were staged according to estimated glomerular filtration rate. Patients with stage ≥3 were accepted as having CKD (study group). These patients were matched with a group of patients without CKD (control group). Operative characteristics, complication rates, and third-month success rates were compared. Results Overall, 339 patients underwent f-URS and 62 (18.28%) had CKD. Control group constituted of 87 patients. Having a solitary kidney (17.4% vs 3.5%; P = .003) and history of stone intervention (51.6% vs 23%; P = .001) were more common in the CKD group. Similarly, access sheath was more commonly used among patients with CKD (87.1% vs 70.22%; P = .015). Both perioperative (19.35% vs 19.54; P = .372) and postoperative (22.6% vs 16.1%; P = .214) complication rates were similar in patients with and without CKD. Hospitalization time was 25.70 ± 25.62 and 24.5 ± 25 hours ( P = .871) for patients with and without CKD, respectively. Although mean third postoperative estimated glomerular filtration rate of patients with CKD did not change significantly (48.16 ± 8.72 vs 49.08 ± 9.26; P = .431), CKD stage of 13 patients shifted from 3 to 2. At the third postoperative month, stone free rate in patients with and without CKD was 87.1% vs 86.2% ( P = .875). Conclusion f-URS is a safe and effective procedure in patients with CKD and it is associated with improved overall kidney function. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of the pelvicaliceal system (PCS) anatomy on the percutaneous nephrolithotomy (PCNL) success rate. Although the caliceal anatomy is effective for stone clearance after shock wave lithotripsy and retrograde intrarenal lithotripsy, the effect of the caliceal anatomy after PCNL has not been evaluated to date. Methods: A total of 498 patients who had undergone PCNL and preoperative intravenous urography were enrolled in our study. Kidney-related anatomic factors, such as the PCS surface area and type, degree of hydronephrosis, infundibulopelvic angle, upper-lower calix angle, infundibular length, and infundibular width were calculated using intravenous urography. The association between the PCNL success rate and kidney-related anatomic factors was retrospectively analyzed using chi-square tests, Fisher''s exact test, Mann-Whitney U test, and forward stepwise regression analysis. Results: A success rate of 78.1% was achieved. No difference was seen the success rates among the PCS types. The mean PCS surface area was 20.1 ± 9.7 cm2 in patients with successful outcomes and 24.5 ± 10.2 cm2 in patients with remaining stones (P = .001). The mean infundibulopelvic angle, upper-lower calix angle, infundibular length, and infundibular width were similar in both groups. Multivariate binary logistic regression analysis showed that stone configuration and PCS surface area were independent factors affecting the PCNL success rates. Conclusion: The results of our study have shown that the PCS surface area is the only anatomic factor that affects the PCNL success rate and patients with a PCS surface area <20.5 cm2 have greater PCNL success. [Copyright &y& Elsevier]

Objectives: To evaluate the outcomes, complications, and early and late postoperative kidney function of percutaneous nephrolithotomy (PCNL) in patients with solitary kidneys. Methods: Between 2002 and 2009, 47 patients with a solitary kidney (congenital in 10 patients, 21.3%; contralateral nephrectomy in 22 patients, 46.8%; and nonfunctional kidney in 15 patients, 31.9%) underwent PCNL. Serum creatinine was measured preoperatively, on postoperative day 1, and at each follow-up visit at regular intervals. The 4-variable modification of diet in renal disease equation was used to calculate the estimated glomerular filtration rate (eGFR). The 5-stage classification of chronic kidney disease (CKD) was used according to the National Kidney Foundation published guidelines. Of 47 patients, 44 were followed least 6 months, whereas 3 patients were lost to follow-up. Results: Success was achieved in 84.5% (40/47) of patients after 1 session of PCNL. Complex stones were detected in 32 (68.1%) patients. Among all patients, 23.4% (n = 11) of them required multiple accesses. Complications developed in 5 (10.6%) patients. At a mean follow-up time of 18.7 ± 11.8 (6–60) months, the overall success rate improved to 97.7% after auxiliary treatments. eGFR was 76.4 ± 27.1, 73.4 ± 26.1, and 83.5 ± 29.4 per 1.73 m2 during preoperative period, immediate postoperative period, and at the last follow-up visit (>6 months), respectively (P < .001). According to CKD classification, kidney function was stable, improved and worse in 63.6% (n = 28), 29.5% (n = 13), and 6.8% (n = 3) of patients, respectively, compared with preoperative levels. Conclusions: PCNL is safe and has an acceptably low complication rate in patients with solitary kidneys. At long-term follow-up, renal function had stabilized or improved in more than 90% of patients with a solitary kidney after PCNL. [ABSTRACT FROM AUTHOR]

Numerous occurrences of hydrated minerals (e.g., phyllosilicate, sulfate) have been found on the surface of Mars by remote sensing and in-situ exploration missions, providing strong evidence of the aqueous environment in Martian history. However, the detailed origin of these hydrated minerals is often controversial, reducing their usefulness in constraining the aqueous history of Mars. For instance, in Ophir Chasma, the origins of hydrated sulfates are debatable among hypotheses of precipitating from groundwater, paleolake, or meteoric water. In this study, we performed detailed mineralogy, morphology and stratigraphy analyses of the hydrated phases in the mineral bowl, a depression between the southern wall and mensa of Ophir Chasma, using datasets from Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), High Resolution Imaging Science Experiment (HiRISE) and High Resolution Stereo Camera (HRSC). A large number of monohydrate sulfates (MHS), polyhydrated sulfates (PHS) and some jarosite were identified in this region. Elevation of PHS-rich regions (mean elevation of −1130 ​m) is higher than those of MHS (mean value of −1401 ​m). Spectra of poly- and monohydrated sulfates mixtures were investigated in details in laboratory. Spectral features (i.e., band depth of ~1.9 ​μm, 2.1 ​μm, convexity at 2.1 ​μm and 2.4 ​μm) of sulfates mixtures changed regularly with the abundance of endmember. The linear function between the ratio of BD2100_2 to SINDEX2 and kieserite component was set up to estimate hydrated sulfates abundance. We employ the function onto CRISM data and find a coexistence of poly- and monohydrated sulfates for the formerly recognized PHS endmember, which may indicate a local dehydration/rehydration process for the sulfated minerals. Comprehensive mineralogy, topography, and stratigraphy analyses of hydrated sulfates outcrops suggest a complex formation scenario which could include surface runoff, paleolake, even aeolian erosion. • Spectral features at ~2 ​μm derived from laboratory sulfates mixtures changed regularly with the abundance of endmembers. • We calculated the abundance of hydrated sulfates in Ophir Chasma using CRISM spectral dataset. • Alternative formation scenarios of sulfates in the mineral bowl of Ophir Chasma were detailed discuss. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Apolipoprotein E (ApoE) is a lipid transport protein with expanded functions in cellular responses to tissue injury, immune regulation and cell growth. ApoE directs vascular changes that contribute to arterial protection as evidenced by the fact that isoforms of ApoE and ApoE deficiency correlate closely with accelerated plaque growth. The N-terminus of the ApoE protein has well-characterized functions, displaying lipid-binding and anti-atherogenic activity, whereas the function of the C-terminus is only partially defined. We have assessed the effects of a 14 amino acid C-terminal ApoE peptide, termed Ep1.B (239–252), on intimal neoplasia in animal models. This peptide is a fragment of a naturally processed peptide (236–252) of murine ApoE. Methods and results: Ep1.B injection reduced neointimal hyperplasia after vascular surgery in rats and mice. When given during early plaque progression in ApoE-deficient mice, Ep1.B injections also prevented plaque growth. Treatment with Ep1.B did not, however, reduce established plaque growth in older mice. Peptides with alanine substitution of amino acid 249, Ep1.N, and with complete sequence reversal, Ep1.R, did not consistently inhibit plaque growth. Conclusion: A naturally processed C-terminal ApoE peptide, Ep1.B, has anti-atherogenic activity indicating a role for this naturally metabolized peptide in vascular wound healing and lipid homeostasis. [Copyright &y& Elsevier]

Despite the potential of anti-thrombogenic coatings, including heparinized surfaces, to improve the performance of blood-contacting devices, the inevitable deterioration of bioactivity remains an important factor in device failure and related thrombotic complications. As a consequence, the ability to restore the bioactivity of a surface coating after implantation of a blood-contacting device provides a potentially important strategy to enhance its clinical performance. Here, we report the regeneration of a multicomponent anti-thrombogenic coating through use of an evolved sortase A to mediate reversible transpeptidation. Both recombinant thrombomodulin and a chemoenzymatically synthesized ultra-low molecular weight heparin were repeatedly and selectively immobilized or removed in a sequential, alternating, or simultaneous manner. The generation of activated protein C (aPC) and inhibition of activated factor X (FXa) was consistent with the molecular composition of the surface. The fabrication of a rechargeable anti-thrombogenic surface was demonstrated on an expanded polytetrafluoroethylene (ePTFE) vascular graft with reconstitution of the surface bound coating 4 weeks after in vivo implantation in a rat model. • Rechargeable surface bound assembly of synthetic ultra-low molecular weight heparin. • Rechargeable multicomponent thin film displaying anti-FXa and aPC generating activity. • Rechargeable anti-thrombotic coating on an ePTFE graft after in vivo blood contact. [ABSTRACT FROM AUTHOR]