多层螺旋CT在肺动脉栓塞中的应用分析

目的：探讨多层螺旋∞书动脉血管成像（spiral CT pulmonary angiography，SCTPA）技术对肺动脉栓塞（pulmonary embolism，PE）的诊断价值。方法：收集SCTPA检查并证实为PE的患者44例，采用多层螺旋CT机行肺动脉增强检查，并行CT后处理包括多平面重建（MPR）、最大密度投影（MIP）和容积再现（VR）重建。结果：本组44例PE行SCFPA检查，均能显示肺栓塞的部位、范围、血管狭窄程度，其中中央型78支，占32．6％，附壁环型84支，占35．2％，完全闭塞型35支，占14．6％，不完全闭塞型42支，占17．6％。急性PE的CT征象主要为“截断征”．“双轨征”，慢性PE的CT表现为腔内偏心或附壁充盈缺损。结论：螺旋CT肺动脉血管成像是脉栓塞的无创、快速、敏感性和特异性均较高的诊断方法。     

64排螺旋CT扫描对肺栓塞的诊断价值分析

目的评价64排螺旋CT肺动脉血管造影（CTPA）对肺栓塞（PE）的诊断价值。方法对临床疑诊急性PE的72例患者进行CTPA检查,并进行多平面重建（MPR）、最大密度投影（MIP）及容积重建技术（VR）。结果 72例患者中确诊为PE患者29例,共累及476处肺动脉及分支,其中,右肺动脉主干36处,左肺动脉主干42处,肺叶动脉157处,肺段动脉203处,亚段动脉38处。CTPA征象分为直接和间接征象,直接征象：肺动脉主干或分支内混合性、附壁性、中心性充盈缺损;间接征象：局限性肺纹理稀疏,肺动脉高压,右心室增大,胸腔积液等。结论 64排CTPA具有准确、快速、无创伤等优点,可立体、直观地观察到肺动脉血栓的大小、分布及范围,并可观察患者的肺内间接改变,是临床诊断及观察疗效的首选方法。     

螺旋CT肺动脉造影在诊断肺动脉栓塞症中的临床应用价值

目的探讨螺旋CT肺动脉造影(computed tomography pulmonary angiography,CTPA)在诊断肺动脉血栓栓塞症(PTE)中的临床应用价值。方法回顾性分析2006年7月至2008年10月经CTPA诊断的8例肺动脉血栓栓塞患者的CT征像。结果8例经CTPA确诊的PTE病例,共累及86支肺动脉(51.1%)。受累肺动脉位于右肺56支(65.1%),肺段动脉受累58支(67.4%)。栓子形态包括完全充盈缺损16支,中心充盈缺损18支,偏心性部分充盈缺损39支,附壁充盈缺损13支。PTE的间接征象主要包括肺动脉高压、肺梗死灶形成、胸腔积液和支气管动脉扩张等。结论螺旋CT进行CTPA检查具有快捷、无创、安全等特点,是诊断肺动脉血栓栓塞症(PTE)的首选检查。     

16层螺旋CT在肺动脉栓塞诊断中的应用

目的 研究16层螺旋CT在肺动脉栓塞诊断中的应用价值.方法 使用GE LightSpeed16 16层螺旋CT机对12例肺栓塞病人行造影增强扫描,将原始数据进行重建再处理.结果 共分析12例病人738支肺动脉,其中193支肺动脉分支显示栓塞,占26.2%.直接征象为充盈缺损,包括:中心型充盈缺损30支,偏心型充盈缺损102支,附壁血栓16支,完全闭塞15支;间接征象包括:马赛克征1例,肺梗死3例,胸腔积液4例,肺动脉高压2例.结论 16层螺旋CT肺动脉造影方便、快捷、无创,可以作为诊断肺栓塞的首选方法.     

MSCT在肺动脉栓塞诊断中的应用

目的探讨肺动脉栓塞(PE)的多层螺旋CT(MSCT)表现特征,研究16层螺旋CT肺血管造影在肺动脉栓塞诊断中的应用价值。方法回顾分析27例临床诊断PE患者的16层螺旋CT肺动脉造影资料的影像学表现,并与其肺动脉造影(DSPA)或随访结果相对照。结果本组27例均与临床诊断相符,中心型11例,周围型13例,混合型3例。螺旋CT肺动脉造影对叶及叶以上肺动脉的显示率达100%,检出PE阳性14支,段肺动脉清楚显示435支(显示率达81.0%),检出PE阳性77支,亚段肺动脉清楚显示801支(显示率达74.3%),检出PE阳性55支。PE的直接征象包括血管腔完全闭塞、部分充盈缺损、轨道征和附壁血栓;间接征象有肺梗死灶、“马赛克”征、右室增大和/或肺动脉扩张、胸腔积液、心包积液等。结论多层螺旋CT肺动脉造影诊断PE简便、安全、无创、准确、可靠,尤其对亚段肺动脉栓塞是一种先进的方法,可以代替有创的肺动脉造影检查。     

螺旋CT肺动脉造影对急性肺血栓栓塞症的诊断价值

目的评估螺旋CT肺动脉造影（SCTPA）在急性肺血栓栓塞症诊断的作用。方法回顾性分析43例急性肺栓塞患者螺旋CT肺动脉造影结果。结果43例患者795支肺动脉分支中254支发生栓塞（32％）,直接征象：部分性充盈缺损152处（60％）、完全性阻塞76处（30％）、轨道征8处（3％）、附壁血栓6处（2％）,灌注减低并密度不均12处（5％）;间接征象：肺动脉扩张13例（30％）、栓塞近端肺小动脉异常增粗6例（14％）、局部肺纹理稀疏、纤细22例（51％）、马赛克征3例（7％）、胸腔积液7例（16％）、肺不张7例（16％）、肺楔形变4例（9％）、磨玻璃影6例（14％）。结论SCTPA是诊断急性肺血栓栓塞症准确、简便、无创伤的有效方法。     

多层螺旋CT在肺动脉栓塞中的诊断价值

目的：探讨多层螺旋CT在肺动脉栓塞中的诊断价值。方法16例肺动脉栓塞患者均使用多层螺旋CT行平扫以及造影增强扫描,采集图像。结果图像显示患者有栓塞肺动脉98支,其中肺动脉干及左、右肺动脉4支,叶肺动脉26支,段肺动脉28支以及亚段肺动脉40支;直接征象为中心型充盈缺损有7支,占7.1%,偏心型充盈缺损有79支,占80.6%,附壁环型充盈缺损有8支,占8.2%,闭塞型充盈缺损有4支,占4.1%;间接征象为双肺见斑片状渗出灶及实变影2例,纤维条索影11例,伴胸腔少量积液3例,患者的间接征象表现为肺灌注不均。结论多层螺旋CT在肺动脉栓塞的诊断中效果显著,同时具有快速、有效及无创伤等特点,在临床诊断中具有重要意义。     

64层螺旋CT肺动脉成像在肺动脉栓塞中的诊断价值

目的探讨应用64层螺旋CT肺动脉造影(CTPA)技术在诊断肺动脉栓塞中的临床价值。方法对商丘市第三人民医院2009年3月一2011年8月患者临床资料进行回顾性分析。结果本组31例患者经CTPA检查图像均显示良好,左右肺动脉、肺动脉主干及肺叶、段、亚段动脉的显示也令人满意。共累及亚段及亚段以上肺动脉252条,受累部位的直接征象为不同大小和不同程度的充盈缺损,间接征象则为肺梗死及胸腔积液等。受累的252条肺动脉中右肺动脉栓塞155条,左肺肺动脉栓塞97条。结论 CTPA对肺动脉栓塞的部位、范围及管腔狭窄程度显示良好,肺动脉阻塞指数可判断肺动脉栓塞的严重程度,为临床选择治疗方法及判定预后提供帮助。     

肺动脉血栓64排螺旋CT肺动脉造影影像分析

目的通过对肺动脉血栓的影像分析，认识肺动脉血栓的动态变化和溶栓效果的联系，为临床抗凝治疗提供更多信息。方法回顾33例临床确诊的肺动脉栓塞患者的影像，分别从形态和密度进行分类，并结合溶栓治疗效果进行分析。结果64层螺旋CT肺动脉造影（CTPA）共检出PE受累动脉560支，2级分支34支，3级分支83支，4级186支，5级152支，6级分支105支。通过统计肺动脉血管管腔中心充盈缺损形血栓的治疗效果较好，有效率达79．31％。附壁充盈缺损凸向腔内或血管分支没有增强的血栓治疗有效率分别是68．75％和65．22％，附壁充盈缺损并凹向腔壁有效率28．57％。低密度血栓溶栓治疗有效率最好，达85．71％，其次为等密度血栓。血栓密度越高，溶栓效果越不理想。结论根据肺动脉血栓的形态及密度特点，能够提示血栓形成时间，并为临床提供有价值的资料。     

螺旋CT在肺动脉栓塞诊断的价值

目的:探讨多层螺旋CT对诊断急性肺动脉栓塞(PE)的临床应用价值.方法:对18例临床疑似肺动脉栓塞病例在进行肺部螺旋CT平扫后再进行多层螺旋CT肺动脉造影检查,并对原始图像进行多平面重建及三位重建.结果:18例疑似PE病例检出15例.15例PE患者中发现32支肺段以上肺动脉发生PE,CT直接征象:充盈缺损(中心性和偏心性)、附壁血栓及完全性阻塞;间接征象:"马赛克"征、胸膜下梗死灶、肺动脉高压、胸腔积液、心包积液;其中MPR和MIP对栓子显示肺动脉内血栓部分或完全充盈缺损改变,多平面重建显示较三位重建效果更好.结论:多层螺旋CT肺动脉造影检查是诊断PE有效、安全、迅速的首选方法,能代替X线肺动脉造影.     

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.

     

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.     

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.     

2-(Acetoxyphenyl)-(Z)-styryl sulfides as cyclooxygenase inhibitors

2-(Acetoxyphenyl)-(Z)-styryl sulfides are described as selective cyclooxygenase-2 (COX-2) inhibitors, useful for treating inflammation and COX-2-mediated disorders including neoplasia. 2-(Acetoxyphenyl)-(Z)-styryl sulfide is claimed to be the most potent COX inhibitor in the series with a COX-2 selectivity ratio of 33. This compound is also claimed to be superior to celecoxib (Celebrex^®, Pfizer) in inhibiting cell growth of colorectal carcinoma cells. In this evaluation, the COX inhibitory activity of this compound is compared to that previously disclosed for diarylheterocycles and 2-(acetoxyphenyl)alkyl sulfides. The validity of the DLD-1 cell line in the growth inhibition studies is questioned based on recent literature reports indicating the lack of COX-2 expression in this cell line.     

Sleep-disordered breathing with chronic opioid use

Chronic opioid use for pain relief or as substitution therapy for illicit drug abuse is prevalent in our societies. In the US, retail distribution of methadone and oxycodone has increased by 824 and 660%, respectively, between 1997 and 2003. μ-Opioids depress respiration and deaths related to illicit and non illicit chronic opioid use are not uncommon. Since 2001 there has been an emerging literature that suggests that chronic opioid use is related to central sleep apnoea of both periodic and non-periodic breathing types, and occurs in ～ 30% of these subjects. The clinical significance of these sleep-related abnormalities are unknown. This review addresses the present knowledge of control of ventilation mechanisms during wakefulness and sleep, the effects of opioids on ventilatory control mechanisms, the sleep-disordered breathing found with chronic opioid use and a discussion regarding the future research directions in this area.     

Drug targets for cognitive enhancement in neuropsychiatric disorders

The investigation of novel drug targets for treating cognitive impairments associated with neurological and psychiatric disorders remains a primary focus of study in central nervous system (CNS) research. Many promising new therapies are progressing through preclinical and clinical development, and offer the potential of improved treatment options for neurodegenerative diseases such as Alzheimer's disease (AD) as well as other disorders that have not been particularly well treated to date like the cognitive impairments associated with schizophrenia (CIAS). Among targets under investigation, cholinergic receptors have received much attention with several nicotinic agonists (α7 and α4β2) actively in clinical trials for the treatment of AD, CIAS and attention deficit hyperactivity disorder (ADHD). Both glutamatergic and serotonergic (5-HT) agonists and antagonists have profound effects on neurotransmission and improve cognitive function in preclinical experiments with animals; some of these compounds are now in proof-of-concept studies in humans. Several histamine H3 receptor antagonists are in clinical development not only for cognitive enhancement, but also for the treatment of narcolepsy and cognitive deficits due to sleep deprivation because of their expression in brain sleep centers. Compounds that dampen inhibitory tone (e.g., GABA_A α5 inverse agonists) or elevate excitatory tone (e.g., glycine transporter inhibitors) offer novel approaches for treating diseases such as schizophrenia, AD and Down syndrome. In addition to cell surface receptors, intracellular drug targets such as the phosphodiesterases (PDEs) are known to impact signaling pathways that affect long-term memory formation and working memory. Overall, there is a genuine need to treat cognitive deficits associated with many neuropsychiatric conditions as well as an increasingly aging population.