正电性多肽copoly(Lys/Tyr)与磷脂膜的相互作用研究

目的 研究正电性多肽copoly(Lys/Tyr)(CPLT)在模拟生物膜上的透过性。方法 ①配制由卵磷脂(EPC)、2-油酰基磷脂酰乙醇胺(DOPE)和大豆磷脂(SBPL)组成的二分子磷脂膜。②Zeta电位测定法(zeta potential method，ZP)测定由上述磷脂组成的脂质体在加入CPLT后的膜表面Zeta电位。③园二色谱法(circular dichroism spectrcvscopy，CD)检测CPLT分子与磷脂膜作用时的构象情况。④电生理学方法(electrophy siology tech—nique，ET)测量CPLT分子在磷脂膜上引起的跨膜电流。⑤荧光光度分析法(fluorescence spectroscopy，FS)检测CPLT分子与磷脂膜的作用过程中的荧光强度变化。⑥共焦点激光扫描显微分析法(confocal laser scanning microscopy，CLSM)研究CPLT在磷脂膜上透过及其相对透过效率。结果①随着CPLT的加入和其浓度的增加，磷脂膜Zeta电位逐渐增加并趋向饱和。②CPLT分子在水相取β-sheet构象，当与磷脂膜结合后，其β-sheet构象的波峰发生红移，但构象基本不变。③CPLT分子能在一定浓度和一定外加电压条件下，透过二分子磷脂膜引起膜电流。④CPLT与磷脂膜的作用可分为三步：第一步，CPLT分子吸附于磷脂膜上；第二步，CPLT分子通过磷脂膜的疏水区；第三步，CPLT分子从二分子膜的内膜解吸，进入膜内水相。⑤CPLT分子在磷脂膜上的透过效率主要决定于磷脂膜的组成，在磷脂膜中存在带负电性的磷脂时可降低CPLT分子在磷脂膜上的透过效率。⑥在最初的CPLT分子与磷脂膜的相互吸附过程中，CPLT分子与磷脂膜间的静电作用力起主要作用。结论copoly(Lys／Tyr)分子能透过二分子磷脂膜，其透过效率主要决定于磷脂膜的组成。在最初的肽一膜吸附过程中，当存在静电作用力时，静电力起主要作用，疏水效应次之。     

Hyperferritinemia in Malignant Histiocytosis, Virus-Associated Hemophagocytic Syndrome and Familial Erythrophagocytic Lymphohistiocytosis

ABSTRACT. Data on 28 patients with malignant histiocytosis (MH), fourteen patients with virus-associated hemophagocytic syndrome (VAHS) and two patients with familial erythrophagocytic lymphohistiocytosis (FEL) were collected from 21 hospitals in Japan to study the serum ferritin levels and clinical features. At diagnosis, the serum ferritin values were a median of 3000 ng/ml (range, 59–270000 ng/ml) in MH and 10500 ng/ml (range, 44–68600 ng/ml) in VAHS/FEL. Clinical signs and symptoms were not substantially different between MH and VAHS/FEL. Thus, serum ferritin markedly increased in the majority of MH/VAHS/FEL patients and should be a useful marker of disease activity in either neoplastic or reactive histiocytic proliferative disorders.     

Ultrastructural studies of epidermal lesions in pityriasis lichenoides chronica

Very early skin lesions from four patients with pityriasis lichenoides chronica were examined by electron microscopy. Aggregates of tubular structures, which resembled those reported in endothelium in lupus erythematosus and are currently being observed in an increasing variety of conditions, were noticed in the epidermal cells of all patients. These cells also showed intracytoplasmic desmosomes, and isolated mitochondria and myelin-like figures in intercellular spaces, in addition to the occurrence of vacuoles and lysosomes in the cytoplasm, dilatation of endoplasmic reticulum and alteration of mitochondria. Occasionally, epidermal cells were seen to be individually filled with fibrils. These ultrastructural findings seem to indicate that in pityriasis lichenoides chronica some injury to epidermal cells occurs at the early stage of pathological processes, as suggested by light microscope studies.     

Right Atrial Separation Procedure for Eliminating Chronic Atrial Fibrillation Associated with Atrial Septal Defect

Chronic atrial fibrillation (AF) had been documented in a patient with atrial septal defect for 7 years. A right atrial separation procedure was performed for ablation of chronic AF, concomitant with repair of the atrial septal defect, and followed by atrial electrophysiological mapping. A horizontal transectional incision extending to the borders of the atrial septum and the tricuspid annulus was made. Cryolesions of the atrial isthmus between the margin of the upper incision and the tricuspid valve annulus were created at -60†C for 2 minutes at a time. After the operation, the patient had restored normal sinus rhythm during a subsequent follow-up period of 48 months.     

Proteus syndrome with giant myelolipoma in the pelvis

Proteus syndrome is a very rare and complex disorder with malformations and overgrowth of multiple tissues. This disorder was designated Proteus syndrome by Wiedemann et al. to denote its variable clinical expression. Our patient presented with macrodactyly, cerebriform appearance and a huge abdominal mass. A biopsy under laparotomy was performed, and histopathological examination revealed myelolipoma. Tumor resection was performed. To our knowledge, no case of Proteus syndrome presenting a myelolipoma in the retroperitoneal cavity has been reported before.     

Evaluation of the Sclerotherapeutic Efficacy of Ethanol, Polidocanol, and OK-432 Using an In Vitro Model

BACKGROUND Sclerosants are used to treat vascular malformations. Owing to variations in the flow, the injected concentrations and the duration of exposure of these sclerosants are altered. Therefore, the clinical effectiveness of sclerotherapy is variable.
OBJECTIVE The objective was to evaluate the differences in clinical response, usually observed among ethanol, polidocanol, and OK-432, using an in vitro sclerotherapy model.
METHODS Endothelial cells were cultured and exposed to different concentrations of the sclerosants for 5 seconds and the remaining viable cells were counted using a MTT assay kit. Dyes were used to visualize the morphologic changes. Precipitant formation in blood was also evaluated. Finally, the degree of ICAM-1 expression, after exposure to lower concentrations of these sclerosants, was studied using immunocytochemistry.
RESULTS Only ethanol causes precipitant formation and kills almost all cells from 30% concentration. Polidocanol begins to disrupt the cell membrane from 0.0125% onward. Only OK-432 induces ICAM-1 expression.
CONCLUSION Ethanol's strong precipitant-forming effect may induce thromboembolism, thus enhancing sclerosis. Polidocanol's endothelial cell–lysing effect was clearly documented. OK-432 may mediate its effect by inducing inflammatory response of the endothelium via ICAM-1 expression. This in vitro model may be useful in evaluating other sclerosants as well.     

Coexistence of proguanylin (1–15) and somatostatin in the gastrointestinal tract

In order to identify proguanylin-secreting cells, we have raised an antiserum against the synthetic fragment of human proguanylin (1–15) and have examined the proguanylin-positive cells in the human and rat gastrointestinal tract by immunohistochemical methods. Numerous proguanylin (1–15)-immunoreactive cells were found in the gastrointestinal tract. They were either pyramidal or spindle shaped in the stomach. Spindle-shaped cells, frequently possessing long slender processes, were located at the base of the pyloric epithelium and did not extend to the lumen. In the duodenum and jejunum, these cells were mostly pyramidal in shape and often had a slender process towards the lumen. The immunostaining was completely blocked by the human proguanylin (1–15) fragment. Paneth and goblet cells were negative against this antiserum. The number of serotonin-positive cells was much larger than that of proguanylin-positive cells in all the segments tested. The number of proguanylin-positive cells decreased from the jejunum to the ileum and very few cells were observed in the colon. In contrast to serotonin-positive cells, most somatostatin-positive cells were also positive for proguanylin. Thus, proguanylin (1–15) or its related protein appears to coexist with somatostatin in intestinal endocrine D cells which may be a source of circulating proguanylin. Proguanylin, like somatostatin, may also regulate intestinal function as a local regulator.