Leukocyte-connective tissue cell interaction. II. The specificity,duration, and mechanism of interaction effects

Human fibroblasts grown in vitro as monolayer cultures were “activated” by syngeneic lymphocytes, polymorphonuclear leukocytes, and fibroblasts as well as by allogeneic leukocytes, human embryonic kidney cells, fibroblasts, and thrombocytes. “Activation” was characterized by increased medium acidity, increased glucose uptake, increased lactate formation, and marked stimulation of hyaluronic acid formation. The “activation” process was blocked by preincubation with actinomycin D, but not by incubation with 2,4 dinitrophenol. “Activated” fibroblasts continued to exhibit increased mucopolysaccharide synthesis for 5 to 28 days following a single exposure to stimulatory materials.     

The interaction between excimer laser energy and vascular tissue

The effects of XeF1 excimer laser on isolated normal and atherosclerotic aorta were studied. Experiments were performed in flowing water at constant temperature, flow rate, water depth, pulse width (10 nsec), wavelength (351 nm), beam size (1 mm2) and focal length (50 cm). The number of pulses, the pulse energy, and the pulse frequency were varied, and the vascular tissue was studied histologically. The following observations were made: tissue ablation required a minimum threshold pulse energy and was nonlinearly proportional to the number of pulses and the pulse energy delivered; precise tissue ablation occurred at low pulse frequencies, but changes resembling a thermal process were seen as pulse frequency increased; calcified plaque was more photoresistant than atheroma or normal vessel; excimer laser energy was markedly attenuated by blood; and the time interval between pulses and high peak power are related to the precision of ablation by pulsed excimer laser. It is concluded that excimer laser can rapidly and precisely ablate vascular tissue by a photothermal process.     

The importance of angiogenesis in the interaction between polymeric biomaterials and surrounding tissue

The uncomplicated outcome of surgical interventions after biomedical application of biomaterials depends on successful wound healing. Wound healing is a highly complex process compossed of a number of overlapping phases, including inflammation, epithelialization, angiogenesis and matrix deposition. Inadequate angiogenesis limits the transport between the microvasculature and implanted biomaterials. The regulation of angiogenesis is based on numerous growth factors, proteolytic enzymes, extracellular matrix components, cell adhesion molecules, and vasoactive factors. Capillary endothelial cells were grown for different time periods (day 1, 3, 6, 9 and 12) on the surface of a recently developed biodegradable polymeric biomaterial. As control the cells were seeded on the gelatine coated polystyrene surface of commercially available cell cultures dishes. Endothelial cells became adherent and showed confluent cells layers during increasing time period on both surfaces. The total cell number of cells grown on the gelatine coated polystyrene surface was higher in comparison to the polymer surface. The chorioallantois membrane (CAM) assay was used as a sensitive assay to investigate the influence of angiogenesis in vivo. After 48 hours of exposure of the CAM to polymer samples no avascular zones, free of capillaries and/or thrombosis or hemorrhage were detectable. Considering the biofunctionality of our recently developed polymer in these experiments different surface modifications of the polymer are the topic of current investigation to support the biomaterial-microvasculature interactions in vivo.     

The effect of guidewires during electrosurgical sphincterotomy.

We describe six electrosurgical incidents and one complication which occurred during guidewire-assisted sphincterotomy. Studies were conducted on three types of guidewires: Teflon painted, Teflon sheathed, and polymer coated. Scanning electron micrographs demonstrated surface imperfections in the painted Teflon guidewire coating, which allowed for potential electrical short circuits between cutting wire and guidewire through a septal defect in a double channel catheter. Septal defects were found in 25% (1 of the 4 tested) of the factory fresh sphincterotomes that were used in this study, and in 10% (6 of 57) of those used clinically. Induced current (capacitively coupled) present on the guidewires was measured at 13 to 30 mA for typical sphincterotomy settings. The induced current on sheathed guidewires, without any insulation defects, was measured at less than 1 mA at typical operating powers. As both short circuits and induced currents place the patient at risk for burns or perforation at the distal end of the guidewire, we suggest the use of a Teflon-sheathed rather than Teflon-painted guidewire, if the wire is to be left in place during sphincterotomy. The Teflon sheath offers the thickest insulation, a very low probability of surface defects, and therefore a high index of safety.     

The complex interaction between overweight,hypertension, and sympathetic overactivity

There is ample evidence in the epidemiological and clinical literature that hypertension and overweight are closely and causally interrelated. Sympathetic nervous system (SNS) overactivity has been well documented in both hypertension and overweight, but it is not clear whether this is a coincidental finding or whether the association reflects a mechanistic role of SNS in these two interrelated clinical conditions. Whereas in this review we focus on the evidence for a primary role of SNS in the development of hypertension and overweight, it is clear that the process can be initiated from other starting points such as primary overeating or sleep apnea. After overweight evolves, hormones secreted by fat cells further accelerate SNS overactivity, weight gain, and blood pressure increase. The main thesis of this article is that regardless of where the process started, the same clinical picture of hypertension, overweight, and SNS overactivity will emerge. There is good evidence that in genetically prone individuals, prolonged SNS stimulation elicits a down regulation of beta-adrenergic receptors. This in turn decreases the ability to dissipate calories and diminishes the beta-adrenoceptor–mediated vasodilatation. We hypothesize that beta-adrenoceptor downregulation is the linchpin in the association of SNS with overweight and hypertension.     

The electrosurgical knife in an optimized intermittent cutting mode for the endoscopic treatment of benign web-like tracheobronchial stenosis

The established endoscopic treatment of web-like tracheobronchial stenosis is laser vaporization, but the appearance on the market of a new cutting mode with a lower coagulation effect has been proposed as an alternative to laser due to less injury to the tissue.     

The interaction of proinsulin with the insulin-like growth factor-I receptor in human liver, muscle, and adipose tissue.

Because of the sequence homology and tertiary structure similarities between proinsulin (PI) and insulin-like growth factor-I (IGF-I), it is possible that PI interacts with the IGF-I receptor with higher affinity than insulin. To test this hypothesis in man, we have partially purified IGF-I receptors from liver, muscle, and adipose tissue and studied their interaction with PI, insulin, IGF-I, and IGF-II. With some tissue to tissue variation, [125I]insulin binding was 4- to 8-fold greater than IGF-I binding. Unlabeled IGF-I at about 1 x 10(-9 M, IGF-II at about 1 x 10(-8) M, and insulin at about 1 x 10(-6) M displace 50% the binding of [125I]IGF-I to its receptor, whereas PI at 1 x 10(-6) M displaces less than 20% of the binding of [125I]IGF-I to its receptor. We conclude that in human liver, muscle, and adipose tissue, PI does not interact with the IGF-I receptor at a higher affinity than insulin, and the affinity of IGF-I receptors is several-fold lower than that of insulin receptors. It is, therefore, unlikely that if PI were to be administered to man any of its biological effects would be by interacting with the IGF-I receptor.     

The interaction between age and list length in free recall.

Using the "delayed-recall" procedure developed by Shiffrin (1970), the effects of list length on encoding, storage, and retrieval processes in different aged subjects were assessed. The length of a list interpolated in the retention interval did not interact with age, while an interaction was found between age and the length of list being recalled. Age differences in the probability of recall decreased as the length of the list being recalled increased. This interaction was replicated in a second experiment with immediate recall. This interaction seems most compatible with the hypothesis that older persons use less spontaneous organization during list learning. List length primarily disrupts the ability of younger subjects to develop adequate organizational plans (2.e., longer lists are more difficult to organize), and because older subjects are organizing less, they are less affected by the increases in list length.     

Laser tissue interaction in direct myocardial revascularization.

This investigation examines the various laser choices used for transmyocardial laser revascularization (TMLR) with emphasis on the laser-tissue interaction. A series of in vivo (porcine model, n=27) and in vitro experiments were performed to study the effects of CO(2), holmium:YAG, and XeCl excimer lasers on the histological outcome of TMR channels. Computerized histopathological analysis has revealed that the CO(2) and holmium:YAG lasers produce substantial unpredictable thermal damage and differ predominantly in the amount of the mechanical injury or tissue shredding. In comparison, the excimer laser appears to produce the most uniform tissue ablation with the least thermal and shockwave damage.     

The current knowledge about the therapeutic use of endoscopic sclerotherapy and endoscopic tissue adhesives in variceal bleeding

ABSTRACT

Introduction: The most recent guidelines vary in their approach to the management of variceal bleeding especially with the use of endoscopic sclerotherapy (ES) and endoscopic tissue adhesive (ETA). This review highlights their clinical use for variceal bleeding from different guidelines perspectives.

Areas covered: A comprehensive literature review of three major guidelines including the American Association for the Study of Liver Diseases (AASLD) 2017, United Kingdom (UK) guidelines 2015 and Baveno VI Consensus workshop guidelines in 2015 on the use of ES and ETA in variceal bleeding.

Expert opinion: While endoscopic band ligation (EBL) completely replaced endoscopic sclerotherapy (ES) for esophageal varices. There is a valuable use of endoscopic sclerotherapy (ES) and endoscopic tissue adhesive (ETA) especially for patients with gastroesophageal varices (GOV2) and isolated gastric varices (IGV2). The current standard of care heading toward portosystemic shunting with Trans-jugular-Intrahepatic Portosystemic Shunt (TIPS) and balloon retrograde transvenous obliteration (BRTO). However, recent advancement in endoscopic ultrasound (EUS) allowing direct injection of sclerosant and tissue adhesive into the varix bringing promising results in achieving hemostasis and lowering the risk of complications. Also, ES and ETA have great clinical value in achieving hemostasis for isolated (ectopic) varices and stomal varices.     

The interaction between obesity and visceral hypersensitivity

Obesity has been a worldwide problem associated with numerous chronic diseases such as cardiovascular disease, type 2 diabetes, and metabolic disorders. It may also play a role in visceral hypersensitivity, contributing to irritable bowel syndrome. (i) Adipose tissue secretes various inflammatory mediators, causing intestinal hyperpermeability and nerve endings activation. (ii) Obesity and gastrointestinal microbiota could affect each other, and microbial metabolites can increase sensitivity of the colon. (iii) Vitamin D deficiency contributes to both fat accumulation and disruption of the intestinal mucosal barrier. (iv) Brain-gut axis may be another bridge from obesity to visceral hypersensitivity.     

A promising culture model for analyzing the interaction between adipose tissue and cardiomyocytes

The heart has epicardial adipose tissue that produces adipokines and mesenchymal stem cells. Systemic adipose tissue is involved in the pathophysiology of obesity-related heart diseases. However, the method for analyzing the direct interaction between adipose tissue and cardiomyocytes has not been established. Here we show the novel model, using collagen gel coculture of adipose tissue fragments (ATFs) and HL-1 cardiomyocytes, and electron microscopy, immunohistochemistry, real-time RT-PCR, and ELISA. HL-1 cells formed a stratified layer on ATF-nonembedded gel, whereas they formed almost a monolayer on ATF-embedded gel. ATFs promoted the apoptosis, lipid accumulation, and fatty acid transport protein (FATP) expression of FATP4 and CD36 in HL-1 cells, whereas ATFs inhibited the growth and mRNA expression of myosin, troponin T, and atrial natriuretic peptide. Treatment of leptin (100 ng/ml) and adiponectin (10 μg/ml) neither replicated nor abolished the ATF-induced morphology of HL-1 cells, whereas that of FATP4 and CD36 antibodies (25 μg/ml) never abolished it. HL-1 cells prohibited the development of CD44+/CD105+ mesenchymal stem cell-like cells and lipid-laden preadipocytes from ATFs. HL-1 cells increased the production of adiponectin in ATFs, whereas they decreased that of leptin. The data indicate that our model actively creates adipose tissue-HL-1 cardiomyocyte interaction, suggesting first that ATFs may be related to the lipotoxiciy of HL-1 cells via unknown factors plus FATP4 and CD36 and second that HL-1 cells may help to retain the static state of ATFs, affecting adipokine secretion. Our model will serve to study adipose tissue-cardiomyocyte interaction and mechanisms of obesity-related lipotoxicity and heart diseases.     

早期未分化型胃癌与胃黏膜相关淋巴组织 淋巴瘤的内镜下特征差异

目的探讨早期未分化型胃癌（undifferentiated-typed early gastric cancer,UD-EGC）与胃黏膜相关淋巴组织（mucosa-associated lymphoid tissue,MALT）淋巴瘤在白光内镜以及放大内镜窄带光成像（magnifying endoscopy-narrow band imaging,ME-NBI）下的特征性表现。方法回顾2015年3月—2019年7月上海交通大学附属第一人民医院所有留存白光和ME-NBI完整图像资料的病例,比较26例UD-EGC和7例ⅠE1期胃MALT淋巴瘤患者资料。总结分析不同病变在白光内镜和ME-NBI下的特征差异。结果两组患者在年龄、性别、病灶浸润深度等方面差异无统计学意义。在白光内镜下,UD-EGC多为单一病灶,位于胃的下段,边界常不清晰,而MALT淋巴瘤病灶多为多发病灶,位于胃的中段,边界尚清晰。在ME-NBI下,UD-EGC病灶的微表面特征表现为隐窝间区扩张或消失,微血管表现为螺旋状的病理形态,而MALT淋巴瘤常呈现“阡陌交通征”“卵石征”、病灶处残存腺管为幽门螺杆菌相关胃炎表现的微表面特征以及“树样”的微血管特征。幽门螺杆菌根除治疗后,原病灶区域的微表面及微血管形态逐渐恢复正常。结论UD-EGC和胃MALT淋巴瘤在白光内镜下表现为病灶数目、部位和边界特征的不同,在ME-NBI下表现为病灶的微表面和微血管特征的显著差异。对二者内镜特征的识别将有助于减少其在内镜检查中的漏诊和误诊。     

胃静脉曲张内镜下黏合剂栓塞治疗后排胶与再发出血的关联

目的研究胃静脉曲张内镜下黏合剂栓塞治疗后排胶过程与再发出血之间的关联和影响。 方法回顾性分析2010年1月至2017年7月期间,上海交通大学医学院附属瑞金医院消化科病房收治,经胃镜检查明确存在胃静脉曲张,并接受了内镜下黏合剂注射栓塞治疗术的患者,对其行内镜随访至少1年,分析其病史资料、内镜所见、治疗情况及随访结果。 结果总计55例患者接受了内镜下胃静脉曲张黏合剂注射栓塞治疗术,其中男性33例,女性22例,平均年龄(60.0±14.6)岁,其中GOV1型12例(21.8%),GOV2型11例(20.0%),IGV1型32例(58.2%)。共行黏合剂治疗58次,注射部位64点,平均每点注射1%聚桂醇(3.79±1.55)ml,组织黏合剂(3.02±1.17)ml。所有患者在1年的随访期间均生存,10例患者(7例IGV1型,3例GOV2型)再发上消化道出血共11次,其中排胶溃疡未愈8次、静脉曲张再发出血2次、胃角溃疡出血1次。排胶溃疡完全愈合的时间平均为(8.3±3.4)个月,其中36例患者(69.2%)于术后4～9个月完成整个排胶过程。对排胶过程≥12个月的患者共9例随访至2年,所有患者均完成排胶,且随访期间未发生上消化道出血。 结论内镜下黏合剂注射栓塞治疗术为胃静脉曲张破裂出血的重要二级预防手段。黏合剂注射术后排胶为正常现象,术后再发出血可能和曲张静脉栓塞不完全相关,确保曲张静脉完全栓塞或有助于降低术后再发出血风险。     

The interaction between Entamoeba histolytica and Syphacia obvelata infection in mice.

Mice naturally infected with Syphacia obvelata were challenged intracaecally with Entamoeba histolytica trophozoites. They showed a higher level of amoebic infection than mice without worms. Mice with the heaviest Syphacia infection were the most susceptible to amoebic infection. It appears that a concomitant infection with helminthic parasites residing in the caecum alters the outcome of an amoebic infection.