单丝聚丙烯合成非吸收齿状线在美容整形应用中并发症的防治及应用改进

目的探讨单丝聚丙烯合成非吸收齿状线在美容整形中的并发症产生的原因及应用方法及技术的改进。方法对近两年的单丝聚丙烯合成非吸收齿状线在美容整形中的应用进行总结与分析。结果改进应用方法后，并发症明显减少，效果加强。结论单丝聚丙烯合成非吸收齿状线在美容整形中应用得当，可减少并发症、取得显著效果。     

Silicone-Coated Polypropylene Hollow-Fiber Oxygenator: Experimental Evaluation and Preliminary Clinical Use

Background. A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-μm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures.

Methods. Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator.

Results. Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O₂ and CO₂ transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability.

Conclusions. This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.     

动态硫化PP／EPDM强化增韧机理的动态力学研究

采用动态力学试验方法,研究了不同ＥＰＤＭ含量的动态硫化和简单共混两种ＰＰ／ＥＰＤＭ材料动态力学响应的差异及其特征。结果显示：与简单共混ＰＰ／ＥＰＤＭ相比,动态硫化ＰＰ／ＥＰＤＭ具有ΔＴｇ小,内耗峰扩宽程度大,低温和室温内耗峰强度高,所处温度低,６０－７０℃时内耗峰强度发生高低变位,在ＥＰＤＭ相的α转变以下还显示β和γ次级转变等特性。     

Compatibility and stability of bryostatin 1 in infusion devices

Bryostatin 1 is currently in phase II clinical trial sponsored by the National Cancer Institute as an anticancer chemotherapeutic agent. Bryostatin 1 for injection was supplied in a dual pack containing a drug vial and a diluent vial and was manufactured by Ben Venue Laboratories, Inc (Bedford, OH). The stability and compatibility of the bryostatin 1-PET formulation, diluted to 1 and 10 ug/mL in saline and benzyl alcohol preserved saline, with polypropylene (PP) and polyvinyl chloride (PVC) bags at room temperature (27°C) were studied. All experiments were conducted in triplicate and analyses were performed using a validated, stability-indicating, high performance liquid chromatography (HPLC) assay.Bryostatin 1 solutions were compatible with PP bags. At both concentrations and with both salines, the bryostatin content remained unchanged during the 28-day storage period, benzyl alcohol concentration in the preserved saline solutions also remained relatively constant. In PVC bags, however, a decrease in bryostatin 1 concentrations without generation of decomposition products was observed at both dilutions and with both salines during the 28-day storage. A decrease in benzyl alcohol concentration in the preserved saline was also observed. While no diethylhexylphthalate (DEHP) leakage into the solution was observed in PP bags, DEHP leakage in PVC infusion bags was observed on day 2 of storage which increased with storage time and leveled off on day 6. The amount of DEHP leached into drug solution is dependent on the drug concentration. This study suggests bryostatin-PET formulation diluted with preserved saline can be used for long-term (4 week) intravenous administration using PP infusion bags, but not with PVC bags.     

Strengthening Process by Electron Beam to Carbon Fiber for Impact Strength Enhancement of Interlayered Thermoplastic-Polypropylene Carbon Fiber Composite

Strong adhesion between recyclable thermoplastic (TP) polymer and carbon fiber (CF) has always been highly sought after. Therefore, for an interlayered CF reinforced TP polypropylene (CFRTPP) composite composed of 3 sized CF plies, alternating between 4 PP sheets, designated [PP]₄[CF]₃, a process of activating CF plies directly on both sides with homogeneous low energy electron beam irradiation (EBI) under N₂ gas, prior to lamination assembly and hot press of 4.0 MPa at 493 K for 3 min was carried out. Experimental results showed EBI dose of 43.2, 129, or 216 kGy significantly raised Charpy impact values, a_uc at all fracture probabilities, P_f. The 129 kGy dose appeared to be at or near optimum increasing a_uc 103%, 83%, and 65% at low-, median-, and high-P_f = 0.07, 0.50, and 0.93; while raising statistically lowest impact value, a_s at P_f = 0 calculated by 3-dimensional Weibull equation about 110%, indicating increased safety and reliability. It is assumed dangling bonds generated by the EBI rapidly form covalent bonds CF:C:O:C:PP and CF:C:C:PP at the interface, along with cross-linking in the PP near the CF. This is by charge transfer from CF to PP.     

Improved Insulation Properties of Polypropylenes in HVDC Cables Using Aqueous Suspension Grafting

Owing to its lack of crosslinking, polypropylene (PP) is considered an environmentally friendly alternative to crosslinked polyethylene as high-voltage direct current (HVDC) cable insulation. However, pure PP can accumulate space charges under a HVDC, and thus must be modified for use as an insulating material for HVDC cables. In this study, 4-methylstyrene is grafted onto PP using an aqueous suspension grafting method to improve its properties. The effects of the swelling time, reaction time, and 4-methylphenylene concentration on the reaction were investigated. The optimum process conditions were determined, including an optimum grafting ratio of 0.97%. The volume resistivity, ability to suppress space-charge accumulation, and DC breakdown strength of modified PP were also studied. Modified PP with a grafting ratio of 0.88% showed optimal space-charge suppression and the highest volume resistivity and breakdown strength. The work will facilitate the design and development of more efficient insulation materials for HVDC cables.     

Morphological characteristics of tissue reaction in the zone of “Cousin” unwoven polypropylene endoprosthesis implantation

Comparative histological and electron microscopic study of mouse tissues at the site of implantation of Cousin mesh and unwoven polypropylene endoprostheses was carried out. Implantation of unwoven endoprosthesis was associated with more pronounced inflammatory reaction with longer elimination of neutrophilic granulocytes and macrophages from the adjacent tissues. The growth of connective tissue components between the implant fibers with the formation of fine connective tissue capsule enveloping the prosthesis was observed during earlier periods of the experiment. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 143, No. 5, pp. 595–600, May, 2007     

质量提取法测试直立式聚丙烯输液袋包装的葡萄糖注射液密封完整性

目的 建立质量提取法对直立式聚丙烯输液袋包装的葡萄糖注射液(规格：250 mL:12.5 g)的密封完整性进行测试。方法 进行方法参数设定及系统适用性、检出限与检测范围、耐用性、精密度等方法学验证,以及对直立式聚丙烯输液袋包装的葡萄糖注射液(规格：250 mL:12.5 g)加速0、3、6个月样品的密封完整性进行测定。结果 质量提取法方法检出限为3μm;精密度(RSD)为2.07%～5.60%。结论 本次研究采用的质量提取法可以用于直立式聚丙烯输液袋的密封完整性测试,该方法灵敏度较高,操作简单,结果真实可靠。     

Influence of a New Monofilament Polyester Mesh on Inflammation and Matrix Remodeling

ABSTRACT

Synthetic mesh is widely used for hernia repairs, but mesh-induced chronic inflammatory responses may lead to postoperative complications. We previously showed an elevated response to multifilament polyester (PE) versus monofilament polypropylene (PP) and polytetrafluoroethylene (PTFE) meshes, but it is unclear whether this discrepancy is due to the differences in chemical composition or filament structure. This study compares the influence of a newly available monofilament PE mesh to that of multifilament PE, monofilament PP, and monofilament PTFE on the expression of genes important in inflammation and extracellular matrix remodeling in a rat model. Full thickness abdominal wall defects were corrected with onlay repair or suture repair with no mesh. Explants were harvested 7 or 90 days after repair and divided for histology and mRNA analyses using real-time quantitative polymerase chain reaction arrays to profile expression at the tissue-mesh interface. Monofilament PE elicited a reduced foreign body reaction compared to multifilament PE, corresponding with reduced mRNA expression of important inflammatory cytokines and matrix metalloproteinases (MMPs). Unexpectedly, monofilament PE also resulted in markedly reduced mRNA expression of tumor necrosis factor and MMPs 3 and 9 compared to the widely-used monofilament PP mesh. Findings from this study revealed that both chemical composition and filament structure are important mesh characteristics that may affect a patient's wound healing response and clinical outcome, and should be considered by the surgeon when choosing a particular mesh. Although clinical studies are warranted, results in a rodent model suggest that monofilament PE may be more beneficial than the multifilament form for certain hernia repairs.     

Early Necrectomy in Deep Burns of Aesthetically and Functionally Important Areas

Deep burns of aesthetically and functionally important body areas in children may in their later growth and development have a decisive role. Of the total number (2743) of hospitalized children at the Burns Department of the Pediatric Surgery in Zagreb in the last ten years. deep burns of some aesthetically and functionally important body areas were separated and the results of the application of the early necrectomy and immediate grafting method, as recommended by Jan?ekovi?, are analysed. It is concluded that the results, due to the strict and minute application of the method (considered are individual technically important details and solutions) are good in aesthetic and even more so in the functional sense. Very fast recovery of the functions as well as the fact that up till now no surgical corrections for functional disorders were necessary in analyzed areas, along with already known advantages of the early surgical treatment, undoubtfully speak for its application.