Influence of pH on wound-healing: a new perspective for wound-therapy?

Wound healing is a complex regeneration process, which is characterised by intercalating degradation and re-assembly of connective tissue and epidermal layer. The pH value within the wound-milieu influences indirectly and directly all biochemical reactions taking place in this process of healing. Interestingly it is so far a neglected parameter for the overall outcome. For more than three decades the common assumption amongst physicians was that a low pH value, such as it is found on normal skin, is favourable for wound healing. However, investigations have shown that in fact some healing processes such as the take-rate of skin-grafts require an alkaline milieu. The matter is thus much more complicated than it was assumed. This review article summarises the existing literature dealing with the topic of pH value within the wound-milieu, its influence on wound healing and critically discusses the currently existing data in this field. The conclusion to be drawn at present is that the wound pH indeed proves to be a potent influential factor for the healing process and that different pH ranges are required for certain distinct phases of wound healing. Further systematic data needs to be collected for a better understanding of the pH requirements under specific circumstances. This is important as it will help to develop new pH targeted therapeutic strategies.     

大鼠海马结构至额前皮质和外侧隔核的侧支投射——逆行荧光双标记法

本实验用大鼠24只,采用逆行荧光染料示踪法进行双标记研究。将荧光示踪物二盐酸4′-6-双脒基-2-苯吲哚(DAPI)、碘化丙啶(PI)和依文思蓝(EB)注射入额前皮质的边缘下区以及外侧隔核。结果表明用 DAPI 和 PI 配对注射入上述区破时,可见到海马结构的腹侧下托及其 CA_1区颞侧部有明显的双标记细胞,双标记细胞多位于锥体层,偶见于放射层和起层。提示腹侧下托和 CA_1区颞侧部有侧支投射到额前皮质的边缘下区和外侧隔核。     

靛玉红衍生物PHⅡ-7通过抑制c-fos表达抗乳腺癌耐药株MCF-7/ADR增殖

目的:探讨靛玉红衍生物PHⅡ-7抗乳腺癌耐药株MCF-7/ADR增殖作用的初步机制。方法:MTT法检测PHⅡ-7的体外杀伤活性;RT-PCR法、Western blot法检测基因、蛋白表达水平;构建干扰c-fos的短发夹RNA真核表达载体,转染MCF-7/ADR细胞,并建立稳定转染的细胞系;采用细胞计数法绘制生长曲线探讨c-fos表达下调对乳腺癌细胞增殖的影响。结果:PHⅡ-7剂量依赖性地抑制乳腺癌敏感株MCF-7及耐药株MCF-7/ADR增殖;c-fos在耐药株MCF-7/ADR表达明显高于敏感株MCF-7;PHⅡ-7明显抑制c-fos的表达;shRNA显著抑制了c-fos蛋白表达,细胞增殖也被显著抑制。结论:靛玉红衍生物PHⅡ-7浓度依赖性地抑制乳腺癌耐药株MCF-7/ADR增殖,其作用可能与抑制原癌基因c-fos有关。     

PHⅡ-7通过升高ROS诱导K562和K562/A02凋亡

目的探讨靛玉红衍生物——PHⅡ-7对K562和K562/A02的体外杀伤作用及其机制。方法利用WST-8试剂盒、细胞凋亡检测以及活性氧(ROS)检测研究PHⅡ-7对K562和K562/A02发生杀伤作用的机制。共聚焦显微镜及Western blot分析观察药物处理前后细胞的变化。结果细胞毒实验证实PHⅡ-7对K562和K562/A02有相近的杀伤作用。给予上述两种细胞2μmol·L-1PHⅡ-7可见明显的ROS水平升高。PHⅡ-7对K562及K562/A02具有诱导凋亡的作用,呈剂量依赖性。加入ROS的抑制剂NAC可抑制给药后细胞内ROS水平的提高,同时也抑制了PHⅡ-7处理后细胞的凋亡。共聚焦显微镜观察发现药物处理的K562和K562/A02细胞出现明显的凋亡形态改变,Western blot分析表明单用PHⅡ-7可以引起PARP-1及caspase-3,caspase-9的切割,当PHⅡ-7与NAC共同作用之后,上述改变均被抑制。结论 PHⅡ-7可以通过诱导K562/和K562/A02凋亡来实现对上述细胞的杀伤作用,该作用很有可能与其升高细胞内的ROS水平有关。     

细胞表面受体介导的信号通路相关基因对大鼠肝再生的调控作用分析

目的在基因转录水平了解12条细胞表面受体介导的信号通路相关基因对大鼠肝再生的调控作用。方法用搜集网站资料和查阅相关论文等方法获得上述基因,用大鼠基因组230 2.0芯片检测它们在大鼠再生肝中的表达情况,用比较手术和假手术中基因的表达差异性确定肝再生相关基因。结果初步证实上述基因中491个与肝再生相关,其中226个基因之间有742种直接作用关系。细胞因子和趋化因子介导的酶联受体、G蛋白耦联受体、谷氨酸;抗原受体介导的,整合素介导的,脂多糖介导的,Notch、Osmosensory、Smoothened、Toll、Wnt等12条信号通路中与肝再生相关的上调基因数和下调基因数,分别为26和23、164和54、59和51、5和1、22和14、21和10、1和1、4和11、23和11、32和17。肝再生中基因上调表达次数和下调表达次数分别为188和128、464和190、308和207、13和5、88和46、123和50、2和1、20和43、148和30、174和62。结论除Osmosensory和脂多糖介导的信号通路在肝再生中作用较小,Smoothened信号通路作用减弱外,其他9条信号通路在肝再生中作用增强。     

肾移植术后Ⅰ型原发性高草酸尿症复发致移植肾功能不全的多学科综合诊疗

目的  探讨肾移植术后Ⅰ型原发性高草酸尿症（PH）复发的临床特点和多学科综合诊疗（MDT）的经验。方法  对1例接受同种异体肾移植手术后不明原因移植肾功能短期内迅速下降的病例进行MDT讨论,总结MDT在诊断罕见遗传性疾病以及提高肾移植受者长期存活中的作用。结果  经MDT讨论,患者确诊为Ⅰ型PH复发,排除排斥反应后恢复常规免疫抑制方案,嘱大量饮水,予优质蛋白和低磷饮食、维生素B6、钙剂等保守治疗措施并积极防治并发症。患者移植肾功能恶化延缓,但仍在肾移植术后5个月恢复规律血液透析至投稿日。结论肾移植术后Ⅰ型PH复发较为罕见,临床主要表现为复发性肾结石,移植肾功能下降,且并发症多,患者预后不良。通过MDT讨论患者病情,明确诊断,确定最佳治疗方案,延缓了病情进展,改善了患者预后。     

Use of prostaglandin E1 to treat pulmonary hypertension in congenital diaphragmatic hernia

Background/Purpose

Prostaglandin E1 (PGE) has been used to maintain ductus arteriosus patency and unload the suprasystemic right ventricle (RV) in neonates with congenital diaphragmatic hernia (CDH) and severe pulmonary hypertension (PH). Here we evaluate the PH response in neonates with CDH and severe PH treated with PGE.

Testicular hyaluronidase induces tubular structures of endothelial cells grown in three-dimensional collagen gel through a CD44-mediated mechanism.

Cultured brain capillary endothelial cells grown in a 3-dimensional collagen gel can form tubular structures after stimulation by angiogenic factors. We found that treatment of such cultures with testicular hyaluronidase led to formation of tubular structures and cell survival. Anion-exchange chromatography of the enzyme preparation on a MonoQ column revealed the presence of the angiogenic factor basic fibroblast growth factor (bFGF) in the flow-through fraction, as determined by immunoblotting; part of the effect on endothelial cell morphogenesis could thus be ascribed to bFGF. However, adsorbed fractions eluted with increasing concentrations of NaCl, which exhibited hyaluronan-degrading activity at neutral pH, did not contain bFGF but were still able to induce tube-like structures of the endothelial cells. Streptomyces hyaluronidase failed to evoke the same effect. Interestingly, blocking of hyaluronan binding to CD44 receptors by the monoclonal antibody KM114 inhibited the effect of hyaluronidase, but not of bFGF, on endothelial cell tube formation. Our data suggest a CD44-mediated specific role for certain populations of testicular hyaluronidase in the induction of angiogenesis.     

在体耳蜗外淋巴灌流方法

实验证明单纯破损圆窗膜后将人工外淋巴液灌入听泡,可维持稳定、有特征性的耳蜗电图数小时。对本方法的意义及迷路破裂后的耳蜗电图特征结合临床进行了讨论