Randomized study of immune responses to two Tdap vaccines among adolescents primed with DTaP and comparison with results among adolescents primed with DTwP

BackgroundIt has been reported that persons primed with acellular (DTaP) pertussis vaccines have reduced duration of pertussis protection compared with those primed with whole-cell (DTwP) vaccines. However, due to the rapid transition to acellular vaccines, studies attempting directly to compare protection among DTaP-primed vs DTwP-primed individuals are subject to confounding by age and other limitations of ecological studies. Using validated assay results and stored sera from multiple Tdap studies, we evaluated two licensed Tdap vaccines among DTaP-primed adolescents to allow comparison with results obtained in the same laboratory from earlier studies involving DTwP-primed adolescents.MethodsParticipants 11–12 years of age who had received exactly 5 doses of DTaP vaccine prior to 7 years of age were randomly assigned in 2012 to receive one of two licensed Tdap vaccines. Serum specimens obtained pre- and post-vaccination were assayed for responses to the vaccines. Current results were then compared to results obtained in the same laboratory from prior randomized Tdap studies conducted among adolescents primed with DTwP or DTaP.ResultsBoth Tdap vaccines produced strong antibody responses to diphtheria and tetanus; responses to contained pertussis antigens were consistent with the differing levels of those antigens in each Tdap vaccine. However, postvaccination pertussis antibody responses were as much as 71% lower in these DTaP-primed adolescents compared with responses among DTwP-primed adolescents in a prior study of the same two Tdap vaccines. In contrast, results from the present study were similar to those seen in another study of Tdap among DTaP-primed adolescents.DiscussionTaken together, these results from randomized clinical trials provide direct evidence of reduced antibody responses to both licensed Tdap vaccines among adolescents primed with DTaP vaccine, compared with adolescents primed with DTwP vaccine.Clinical trial registry number: ClinicalTrials.gov, NCT01629589.     

脱细胞基质面神经修复材料的制备

目的 制备具有天然神经组织结构的支架,构建组织工程化面神经用于修复面神经损伤。方法 取家兔面神经,改良化学萃取法制备脱细胞神经基质,HE染色形态学观察去细胞及脱髓鞘情况,荧光分光光度计测定支架内细胞经Quant-iT PicoGreen工作液染色后的DNA含量。MTT法检测细胞在支架上的相对生长率从而检测支架的细胞毒性。结果 支架移植体呈圆柱形,弹性与正常神经基本一致,组织观察显示细胞结构未见残余完整细胞及细胞碎片残留,未见神经髓鞘及轴突结构,细胞外基质形成纵向排列结构,结构之间可见空隙。兔脱细胞面神经基质支架内残留的DNA含量较正常兔面神经明显下降(P<0.01)。神经基质供体无细胞毒性。结论 改良化学萃取法可有效去除面神经细胞,天然结构保存完好,细胞毒性低,可作为组织工程化面神经的支架。     

改良消蚀法制备脱细胞真皮基质微粒及其生物相容性评价

目的:利用改良消蚀法制备一种新型脱细胞真皮基质(Acellular dermal matrix,ADM)微粒,并对其相容性加以评价,为组织工程微粒皮肤的制备奠定研究基础。方法:应用机械法切除猪真皮乳头层,结合消蚀法和冻融法除去网状真皮中的所有细胞制备成ADM,将ADM搅碎成颗粒状,对其做细胞毒性实验和皮下埋藏实验检验其相容性。结果:该方法制备的ADM微粒韧性好,细胞去除完全,胶原三维稍松散但结构完整,无基底膜和乳头层。细胞毒性实验显示其基本无毒性,成纤维细胞在ADM微粒上增殖良好,皮下埋藏试验未见明显排异反应,ADM微粒能诱导血管和成纤维细胞长入。结论:用改良消蚀法制备的ADM微粒抗原性低、相容性好,可以作为组织工程微粒皮肤的支架和填充材料。     

静态与动态下脱细胞猪主动脉瓣种植人成纤维细胞初步研究

目的 探索在脱细胞猪主动脉瓣膜材料上种植人成纤维细胞的方法与效果；材料和方法 采用在脱细胞猪主动脉瓣膜材料上静态与动态种植人成纤维细胞，并对其结果进行比较研究。结果 静态种植不能在猪主动脉瓣叶的两侧形成完整的单层人成纤维细胞融合层；而经过动态种植，在一定条件下可以在猪主动脉瓣叶两侧形成完整的单层人成纤维细胞融合层；结论 动态种植较之静态种植易达到形成完整均匀的细胞种植效果。     

异种脱细胞真皮基质在开放性乳突病变切除术中的应用

目的探讨开放性乳突病变切除术后加速乳突术腔上皮化及缩小乳突术腔的有效办法。方法63例行开放性乳突病变切除术的患者按照复查治疗方法分为两组，异种脱细胞真皮组36例，应用异种脱细胞真皮基质覆盖术腔，碘仿纱条组27例，以碘仿纱条填塞术腔。术后随访两组患者，对比观察术腔愈合情况和上皮化时间。结果异种脱细胞真皮组术腔上皮化时间为2～4周，平均2．2周；碘仿纱条组术腔上皮化时间为9～35周，平均13．7周，异种脱细胞真皮组的上皮化时间短于碘仿纱条组（P〈0．01）。结论异种脱细胞真皮基质可促进上皮组织再生，减少术后感染及肉芽发生，加速乳突腔上皮化，提高开放性乳突病变切除术的疗效。     

Successful 18-h acellular extracorporeal perfusion and replantation of porcine limbs - Histology versus nerve stimulation

The current standard for composite tissue preservation is static cold storage (SCS) and is limited to 6 h until irreversible muscle damage occurs. Extracorporeal perfusion (ECP) is a promising technique for prolonged preservation, however, functional results have been scarcely researched. This article assessed neuromuscular function and compared results to histological alterations to predict muscle damage after ECP. Forelimbs of twelve Dutch landrace pigs were amputated and preserved by 4 h SCS at 4–6 °C (n = 6) or 18 h mid-thermic ECP with University of Wisconsin solution (n = 6). Limbs were replanted and observed for 12 h. Sham surgery was performed on contralateral forelimbs (n = 12). Histology analysis scored four subgroups representing different alterations (higher score equals more damage). Muscle contraction after median nerve stimulation was comparable between ECP, SCS, and sham limbs (P = 0.193). Histology scores were higher in ECP limbs compared to SCS limbs (4.8 vs. 1.5, P = 0.013). This was mainly based on more oedema in these limbs. In-vivo muscle contraction was well preserved after 18 h ECP compared to short SCS, although histology seemed inferior in this group. Histology, therefore, did not correlate to muscle function at 12 h after replantation. This leads to the question whether histology or neuromuscular function is the best predictor for transplant success.     

Prevention of pertussis across the age spectrum through the use of the combination vaccines PENTACEL™ and ADACEL™

Acellular pertussis-containing combination vaccines are widely used in the developed world for the control of pertussis and have been successful in controlling disease in preschool-aged children. Combination vaccines formulated for use in adolescents and adults have been developed more recently and are increasingly being implemented for the control of pertussis in these age groups. One such family of products is PENTACEL? (Haemophilus influenzae type b conjugate vaccine reconstituted with component pertussis vaccine and diphtheria and tetanus toxoids adsorbed combined with inactivated poliomyelitis vaccine, DTaP-IPV-Hib), for use in young children, and ADACEL? (tetanus and diphtheria toxoids adsorbed combined with component pertussis vaccine, dTap) for use in adolescents and adults. These products have been demonstrated to be safe, immunogenic and effective for the control of pertussis and the other included diseases.     

The effect of acellular dermal matrix on drain secretions after immediate prosthetic breast reconstruction

Abstract

In recent years the acellular dermal matrix (ADM) has gained popularity in prosthetic breast reconstruction. These procedures involve placement of a closed suction drain in the reconstructed breast. Although it is now widely accepted that ADM has an overall positive effect on the outcome of breast reconstruction, data regarding its effect on postoperative drain secretions is lacking. This study was designed to quantitatively evaluate the influence of ADM on postoperative drain secretions in the setting of immediate prosthetic breast reconstruction (IPBR). This is a prospective, comparative controlled study. Two groups of 16 patients each underwent skin sparing mastectomies (SSM) and IPBR with or without ADM. Closed suction drains were left in all the reconstructed breasts and daily secretion volumes were recorded and compared. Postoperative complications were also noted. Patients in the ADM group showed higher daily and overall secretion volumes compared with patients in the control group (p = 0.014) and the time for removal of the drains was higher by an average of 5 days (13 compared with 8 days, respectively; p = 0.004). There was no correlation between ADM and infection. This study provides the first objective evidence that ADM contributes to elevated and prolonged drain secretions when used for IPBR. This might affect possible prosthesis-related complications (e.g., rotation and malposition, capsular contraction, seroma formation, and infection). This study also noted erythema of the post-mastectomy skin flaps in selected patients, which may be attributable to a local inflammatory reaction to the ADM rather than infection.     

Chemically extracted aceUular allogeneic nerve graft combined with ciliary neurotrophic factor promotes sciatic nerve repair

A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether a chemically extracted acellular allogeneic nerve graft combined with neurotrophic factors provides a good local environment for neural regeneration. This study investigated the repair of injured rat sciatic nerve using a chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor. An autologous nerve anastomosis group and a chemical acellular allogeneic nerve bridging group were prepared as controls. At 8 weeks after repair, sciatic functional index, evoked potential amplitude of the soleus muscle, triceps wet weight recovery rate, total number of myelinated nerve fibers and myelin sheath thickness were measured. For these indices, values in the three groups showed the autologous nerve anastomosis group 〉 chemically extracted acellular nerve graft ＋ ciliary neurotrophic factor group 〉 chemical acellular allogeneic nerve bridging group. These results suggest that chemically extracted acellular nerve grafts combined with ciliary neurotrophic factor can repair sciatic nerve defects, and that this repair is inferior to autologous nerve anastomosis, but superior to chemically extracted acellular allogeneic nerve bridging alone.