结肠黑变病6例临床分析

目的 探讨结肠黑变病（MC）的相关致病因素。方法 回顾分析经电子肠镜检出6例结肠黑变病的临床资料、镜下表现及病理。结果 6例MC均有便秘、服用泻药史，并发大肠息肉2例，大肠癌1例。结论 便秘与滥用泻药为MC的主要病因，MC可能与结肠息肉、大肠癌的发生相关。     

结肠黑变病21例分析

目的 分析结肠黑变病的病因，肠镜下表现及防治措施。方法 对肠镜诊断的21例结肠黑变病进行阿顾性分析。结果 男10例，女11例，年龄24-72岁，平均58岁；均有便秘史，81．0％(17／21)的患者有服用泻药史；2例患者为结肠癌术后。镜下表现为：粘膜色素沉着，可见黄色网格，呈虎皮花斑状弥漫分布于结肠粘膜上，表面光滑，整个肠腔变暗，10例全大肠黑便，11例病变局限于左半结肠；4例伴发息肉，1例合并结肠癌，3例合并结、直肠炎。结论 结肠黑变病是良性可逆性疾病，与便秘、服用泻药等因素有关，应定期随诊：去除便秘的病因是防治的关键。     

结肠黑变病的临床观察

目的探讨结肠黑变病的相关致病因素。方法对经结肠镜检出的44例结肠黑变病的临床资料、镜下表现及病理进行回顾性分析。结果44例中28例便秘,26例有服用泻药史,病变累及全结肠者40例,并发结直肠息肉10例,溃疡性结肠炎1例。结论结肠黑变病主要与便秘、滥用泻药外,可能与结肠息肉,溃疡性结肠炎也有关。     

结肠黑变病13例分析

结肠黑变病是大肠粘膜表面有褐色素沉着，镜下表现为粘膜下巨噬细胞质中含褐色质颗粒。随着结肠镜的广泛应用，对该病的报道日趋增多，我院2002年1月～2004年12月结肠镜检查1160例，检出13例结肠黑变病，检出率1．1％。     

结肠黑变病8例回顾分析

结肠黑变病又称黑素沉着病，是结肠黏膜的一种非炎症性、良性、可逆性的、以色素沉着为特征的病变，临床不多见。近年来，随着结肠镜检查的普及，结肠黑变病检出率逐渐上升，本研究回顾了近几年来我院结肠镜和病理证实的8例结肠黑变病的临床、内镜和病理特点，并复习国内外相关文献，现报告如下。     

207例结肠黑变病的临床及内镜分析

目的探讨结肠黑变病的临床及内镜特征。方法回顾分析2012年1月至2015年12月大连市第三人民医院结肠镜检查207例结肠黑变病患者的临床、内镜及病理特点。结果全结肠累计者36例,占17.4%,横结肠及右半结肠98例,占47.3%,左半结肠47例,占22.7%,累计直肠者26例,占12.7%,合并结肠息肉者32例,占15.5%,合并肠癌者8例,占3.8%。结论结肠黑变病与便秘、长期服用泻药有关,结肠镜检查是诊断结肠黑变病及随访的主要手段。     

结肠黑变病临床分析

目的探讨结肠黑变病的发病率与性别、年龄的关系，与肿瘤的内在联系。方法对55例结肠黑变病患者进行分析，并把小于40岁、40～60岁、大于60岁分三组，观察不同年龄段，不同性别检出率的异同，以及结肠黑变病与肿瘤的关系。结果本组2923例肠镜检查中，发现结肠黑变病55例，检出率1．88％；男女检出率无明显差异；60岁以上检出率明显高于60岁以下患者；结肠黑变病有同时伴有结肠肿瘤的可能。结论结肠黑变病的发生率与性别关系不明显（P〉0．05），与年龄关系明显（P〈0．01）。结肠黑变病与肿瘤发生存在某种联系。     

大肠黑变213例临床分析

目的总结大肠黑变的临床资料,以期为临床诊断、治疗提供依据。方法回顾性分析大肠黑变患者的临床表现、肠镜下表现及受累肠断、病理检查和治疗。结果213例大肠黑变患者均有长期服用果导片、大黄、牛黄解毒丸、排毒养颜胶囊、番泻叶、芦荟胶囊等药物史。肠镜下以肠黏膜色泽改变为主,伴有颗粒增生和息肉。病理可见结肠黏膜固有层内有大量密集或散在分布的含有色素颗粒的单核巨噬细胞。经适当治疗患者0．5—1年后复查肠镜,大肠黑变基本消失。结论大肠黑变病主要由慢性便秘长期口服泻剂引起,病变多集中于近端结肠,有癌变的危险,值得临床重视。     

百癣夏塔热片致结肠黑变病

1例35岁女性患者因全身皮疹加重入院治疗。入院前患者曾服用百癣夏塔热片1年。入院后给予甘草酸单铵盐、氯苯那敏、苯海拉明、阿维A治疗。住院4d后因大便带血行肠镜检查示结肠黏膜呈深棕色。结肠黏膜活检示：黏膜固有层内大量含色素颗粒单核吞噬细胞沉积。诊断为结肠黑变病。停用百癣夏塔热片，其他药物继续使用。1年后，肠镜复查示结肠黏膜恢复正常。结肠黑变病可能和百癣夏塔热片中芦荟所含蒽醌有关。     

结肠黑变病34例内镜检查分析

目的 探讨结肠黑变病的致病因素及与息肉、肿瘤的关系.方法 对确诊的结肠黑变病34例的临床资料,镜下表现及病理进行回顾性分析.结果 长期服用泻药及美容减肥产品通便者28例(82.4%),无服泻药者6例(17.6%),伴结肠息肉12例(35.3%),未发现结肠癌患者.结论 结肠黑变病因可能与便秘及长期服用泻药及细胞凋亡相关,发生率与年龄性别关系不明显,与结肠息肉及结肠癌可能有关;确诊病例应定期肠镜复查随访.     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.