预留缝线延期打结在皮瓣受区的应用

目的总结预留缝线延期打结在皮瓣受区应用的体会。方法 2009年10月—2012年6月,77例皮瓣与受区缝合后张力过高的创面,不强行拉拢缝线闭合创面,而是预留缝线,加强创面换药,留待创面皮瓣肿胀消退,于术后7 d左右收拢缝线打结闭合残余创面。结果本组77例皮瓣与受区预留缝线延期打结闭合的创面全部获得随访,创面愈合后未见明显瘢痕,皮瓣成活良好,皮瓣边缘也未见坏死,创面愈合优良率100%。结论预留缝线延期打结法是闭合皮瓣受区创面的一种较好方法之一,可确保皮瓣成活、促进创面愈合。     

There is no relation between the occurrence of proliferative vitreoretinopathy and the location of the donor site after transplantation of a free autologous retinal pigment epithelium–choroid graft

Purpose: A free autologous retinal pigment epithelium (RPE)–choroid graft can be harvested during transplantation surgery from a 6 or 12 o’clock site in the midperiphery. This study evaluated whether proliferative vitreoretinopathy (PVR) occurs more frequently in patients with an inferior donor site retinotomy, which is not closed by the tamponade and is in contact with the hydrophilic, pro‐inflammatory and fibrotic environment, than in patients with a superior donor site retinotomy. Methods: Retrospective analysis of a prospective cohort of 246 patients with exudative age‐related macular degeneration treated with an RPE–choroid graft transplantation and a lighter‐than‐water, 5000 centistoke silicone oil endotamponade. The location of the donor site, the presence or absence of PVR development and the location of PVR were noted. The two‐tailed Fisher’s exact test was used for statistical analysis. Results: Thirty‐nine of 246 (15.9%) patients developed PVR, of whom 35 had a superior donor site and four an inferior donor site. Of the 209 patients without PVR, 155 had a superior donor site and 25 had an inferior one. For 27 patients, no donor site location was explicitly documented in the patient files. We found no difference between the groups with a superior or inferior donor site and the occurrence of PVR (p = 0.8). Conclusion: Shifting the inflammatory aqueous milieu away from the graft donor site does not prevent the occurrence of PVR.     

羟基磷灰石生物陶瓷在上颌前牙拔牙位点保存的临床应用

目的观察羟基磷灰石生物陶瓷在上颌前牙拔牙位点保存的临床效果。方法 11例17颗上颌前牙因外伤折断拔出后,即刻在拔牙创窝内放置羟基磷灰石生物陶瓷行拔牙位点保存,严密关闭拔牙创窝;术后3,6个月观察缺牙区牙床丰满度及口腔全景x线片,观察拔牙创窝内新骨密度,判断羟基磷灰石生物陶瓷在拔牙位点保存的效果。结果11例患者均无不良症状和体征;x线口腔曲面断层片显示术后3个月羟基磷灰石生物陶瓷植入区有新骨形成,且密度均匀;术后6个月植骨区与周围骨组织无明显界限,新骨形成高度与邻近牙槽骨嵴高度相近。结论羟基磷灰石生物陶瓷具有良好的引导骨再生作用,可减缓拔牙后牙槽骨吸收,达到拔牙位点保存的目的。     

Incorporation of histone derived recombinant protein for enhanced disassembly of core-membrane structured liposomal nanoparticles for efficient siRNA delivery

A novel recombinant protein tetra-H2A (TH) derived from histone H2A has been developed to replace protamine as a conditionally reversible, nucleic acid condensing agent. The novel protein will address the insufficient release of nucleic acid therapeutics, which is captured by protamine for siRNA delivery. TH is composed of 4 tandem repeats of the histone H2A N-terminal sequence, intervened by the cathepsin D cleavage site. The repeating H2A sequence enhances the binding affinity to anionic nucleic acids, forming more stable condensates, as demonstrated by the binding affinity assay. The TH/siRNA condensates are formulated into a core-membrane structured liposomal nanoparticle (NP). The endosomes of cancer cells are rich in cathepsin D, allowing on-site degradation of TH and facilitating the intracellular release of siRNA. The NPs assembled with TH produced a higher silencing efficiency of target genes in vitro and in vivo than the NPs assembled with protamine as the nucleic acid condensing agent. The exploitation of TH in the NP formulation exhibited a biocompatibility profile similar to that of protamine, with minimal immunostimulating and systemic toxicity observed after repeated administration.     

Significance of anaerobic bacteria in postoperative infection after radical cystectomy and urinary diversion or reconstruction

Radical cystectomy followed by urinary diversion or reconstruction (RC) is a standard treatment for patients with muscle-invasive bladder cancer. In these operations, a high frequency of complications, especially postoperative infection, has been reported. However, there have only been a few studies about postoperative anaerobic bacterial infection. To clarify the significance and role of anaerobic bacteria in postoperative infection, we retrospectively analyzed cases in which postoperative infection by these organisms developed. A total of 126 patients who underwent RC from 2006 to 2010 were included in this study. Various types of postoperative infection occurred in 66 patients. Anaerobic bacterial infections were detected with cultures for urine and blood in one case, for blood in two cases, and for surgical wound pus in four. The frequency of postoperative anaerobic bacterial infection in RC was less than that of colon surgery. However, this study revealed the possible development of a nonnegligible number of postoperative anaerobic bacterial infections. Therefore, we should consider anaerobic bacteria as possible pathogens in postoperative infection after RC.     

双侧解剖钢板治疗胫骨平台C型骨折

目的探讨双侧解剖钢板治疗胫骨平台C型骨折的治疗效果。方法回顾分析2000年3月～2002年6月双侧解剖钢板治疗胫骨平台C型骨折22例,随访20例。结果骨折愈合良好,无骨折延迟愈合、骨不连。结论双侧解剖钢板治疗胫骨平台C型骨折效果良好。     

The peach latent mosaic viroid replication initiation site is located at a universal position that appears to be defined by a conserved sequence

Viroids replicate through a rolling circle mechanism that is exclusively RNA dependent. In this study, we initially revisited the determination of the replication initiation sites of peach latent mosaic viroid (PLMVd). A universal initiation site for each of the PLMVd polarities (position A50/C51 and U284 for the plus and minus strands, respectively) that is shared by a relatively wide repertoire of viroid variants was identified, in agreement with a previous report based on a different methodology. Subsequently, an in vitro selection procedure based on a model rolling circle replication assay was developed. This latter experiment led to the identification of a highly conserved CAGACG box which is reminiscent of the sequence found in the vicinity of the PLMVd initiation sites. The conserved sequence contributes to delineating the initiation site and provides an explanation for the presence of a specific universal initiation site on the PLMVd molecule.     

Use of reticulin stain in the diagnosis of intra-uterine gestation

AIMS: The diagnosis of intra-uterine gestation may be problematic when specimens from clinically suspected products of conception lack chorionic villi and/or fetal somatic tissues, since the distinction of intermediate trophoblast from decidual or myometrial elements can be difficult. The placental site is also characterised by stromal changes, including the deposition of a characteristic extracellular fibrinoid matrix. We have noted that these stromal changes may be highlighted by a simple reticulin stain; therefore, we have evaluated reticulin staining in a series of endometrial biopsy specimens from patients with intra-uterine and ectopic gestations. METHODS: Reticulin staining was performed in 28 endometrial specimens from patients with first trimester intra-uterine gestations, including 14 cases that lacked chorionic elements. Eight endometrial samples from patients with concurrent histologically verified tubal ectopic pregnancy were also examined. Selected cases were also studied using a Masson trichrome stain, and immunohistochemically with antisera to cytokeratin and HPL. RESULTS: There was a distinct increase in reticulin staining, usually evident at low power magnification, in most areas of decidua showing implantation site. Prominent reticulin staining was present around the decidual and trophoblast cells and there was also accentuation around stromal vessels, glands and myometrial cells. There was no clear difference in staining within areas of decidua including only rare intermediate trophoblast cells but this pattern was seldom seen in isolation. Minimal changes were seen in the placental site using the Masson trichrome stain. CONCLUSION: Reticulin stains may prove useful in the assessment of endometrial specimens from patients with purported intra-uterine gestations when chorionic elements are not identified. Since the staining technique is simple and can be quickly performed, it could be used as an adjunct to conventional H&E assessment and to select appropriate specimen blocks for additional more sensitive studies, including immunohistochemistry.     

Modeling Recombinant Immunotoxin Efficacies in Solid Tumors

Effectiveness of cancer therapy is improved by the use of recombinant immunotoxins (RITs) that target membrane proteins unique to malignant tumor cells. Although RIT antitumor activity in vivo can always be improved with larger doses, clinical restriction on the dose toleration makes it critical to explore how RIT antitumor activity can be maximized without resorting to dose elevation. In this work, a mathematical model was developed to explore functional correlations between the properties of several recombinant immunotoxins and their antitumor efficacies in vivo. Simulations were compared with experimental data of human tumor xenografts grown on nude mice to assess parameters critical to optimal antitumor activity. We dissected out or held constant as many parameters of the model as possible to investigate the effect of the remaining parameters on the behavior of the system as a whole. Empirical correlations between immunotoxin binding affinity and the target binding site density were obtained for several recombinant immunotoxins targeting either human A431 carcinoma or CD46 Burkitt’s lymphoma. Simulations reinforced the idea of binding site barrier for drug diffusion and suggested that optimal antitumor activity was achieved when the binding affinity is logarithmically dependent on the target binding site density.