环境生物测试技术对沉积物的毒性评价研究

作者采用５种环境生物测试技术对化工沉积物的毒性进行了评价，结果表明化工沉积物对卤虫（海洋生物）、美丽猛水蚤（河口生物）、大型水蚤（淡水生物）及斑马鱼都有一定毒性，其中斑马鱼胚胎仔鱼对化工沉积物的毒性最敏感。作者指出５种环境生物测试技术都可以用来评价沉积物的毒性。     

Radiographic studies of the ventricles in syringomyelia

Summary Radiographic investigations of 171 patients with communicating syringomyelia have been reviewed. Hydrocephalus was found in onethird of the cases and has occasionally progressed after operation on the posterior fossa, sometimes with accompanying clinical deterioration. The outlets of the fourth ventricle were usually abnormal; tonsillar descent, arachnoiditis and both together were seen. Arachnoiditis correlated strongly with a history of difficult birth. The foramen of Magendie was sometimes patent and sometimes blocked. There was no consistent level of occlusion corresponding to a persistent roof of the fourth ventricle. The cisterna magna was usually small or obliterated but some examples of large cisterns or subarachnoid pouches were found. Radiological demonstration of a communication from the fourth ventricle to the syrinx occurred in only seven patients by positive contrast material and not by air. It is suggested that a sizable communication is rare at the time when patients seek treatment.     

Torkildsen shunt as a salvage procedure for an infant with post-hemorrhagic hydrocephalus

IntroductionTorkildsen operation is a ventriculo-cisternal shunt that diverts the cerebrospinal fluid flow from one of the lateral ventricles, via a ventricular catheter, to the cisterna magna of the posterior fossa. It is the first described operation of CSF diversion for the treatment of hydrocephalus [1] (Scarff, 1963).Presentation of caseWe present the case of a premature infant who presented with post hemorrhagic hydrocephalus who underwent several failed CSF diversion surgeries before Torkildsen shunt procedure. The patient overcame the irregularities of CSF circulation that were observed before the operation and his post-operative course was uneventful, in terms of CSF –related complications.DiscussionWe summarize the historical data and the technical aspects of the procedure, and we present a brief literature review of the indications and limitations associated with it.ConclusionTorkildsen shunt can be effective in selected patients with hydrocephalus even in the modern era of computed tomography and magnetic resonance imaging. the procedure enables one to avoid a standard ventriculoperitoneal shunt, especially in cases it is not technically feasible.     

Metabolomic method to detect a metabolite corona on amino-functionalized polystyrene nanoparticles

Abstract

Protein coronas on nanoparticles (NPs) affect their physicochemical properties, cellular uptake, and toxicity, and have been described extensively. To date, studies of the occurrence of small molecule (metabolite) coronas are limited. We sought to determine whether a metabolite corona forms on NPs, using high-sensitivity metabolomics combined with a model system for freshwater ecotoxicology (Daphnia magna feeding on Chlorella vulgaris). Using amino-functionalized polystyrene NPs (NH₂-pNPs), we showed the impact of this material on Daphnia feeding to provide a rationale for the detailed molecular investigations. We then employed a targeted LC-MS/MS approach for sodium dodecyl sulfate (SDS) as an analog to signaling molecules known to occur in our freshwater model system and optimized a corona extraction method for this representative metabolite. Next, we performed an untargeted discovery-based metabolomics study – using high-sensitivity nanoelectrospray direct infusion mass spectrometry (DIMS) – to enable an unbiased assessment of the metabolite corona of NH₂-pNPs in the freshwater model system. Our results demonstrate that SDS was successfully recovered from NH₂-pNPs, confirming that the extraction protocol was fit-for-purpose. Untargeted DIMS metabolomics reproducibly detected 100?s of small molecule peaks extracted from NH₂-pNPs exposed to conditioned media from the D. magna–C. vulgaris model system. Attempts to annotate these extracted metabolites, including by using van Krevelen and Kendrick Mass Defect plots, indicate a diverse range of metabolites that were not clustered into any particular class. Overall we demonstrate the existence of an ecologically relevant metabolite corona on the surface of NPs through application of a high-sensitivity, untargeted mass spectrometry metabolomics workflow.     

Acute toxicity of 50 metals to Daphnia magna

Metals are essential for human life and physiological functions but may sometimes cause disorders. Therefore, we conducted acute toxicity testing of 50 metals in Daphnia magna: EC50s of seven elements (Be, Cu, Ag, Cd, Os, Au and Hg) were < 100 µg l^?1; EC50s of 13 elements (Al, Sc, Cr, Co, Ni, Zn, Se, Rb, Y, Rh, Pt, Tl and Pb) were between 100 and 1000 µg l^?1; EC50s of 14 elements (Li, V, Mn, Fe, Ge, As, In, Sn, Sb, Te, Cs, Ba, W and Ir) were between 1,001 and 100,000 µg l^?1; EC50s of six elements (Na, Mg, K, Ca, Sr and Mo) were > 100,000 µg l^?1; and. 7 elements (Ti, Zr, Bi, Nb, Hf, Re and Ta) did not show EC50 at the upper limit of respective aqueous solubility, and EC50s were not obtained. Ga, Ru and Pd adhered to the body of D. magna and physically retarded the movement of D. magna. These metals formed hydroxides after adjusting the pH. Therefore, here, we distinguished this physical effect from the physiological toxic effect. The acute toxicity results of 40 elements obtained in this study were not correlated with electronegativity. Similarly, the acute toxicity results of metals including the rare metals were also not correlated with first ionization energy, atomic weight, atomic number, covalent radius, atomic radius or ionic radius. Copyright © 2014 John Wiley & Sons, Ltd.     

Effect of subcutaneous suture line and surgical technique on wound infection after saphenectomy in coronary artery bypass grafting: a prospective randomised study

Objective. The aim of the study was to evaluate the impact of an additional subcutaneous suture line on the incidence of postoperative (p.o.) infection at the vena saphena magna harvesting site (VSMHS) after coronary artery bypass grafting (CABG). Methods. Two hundred and forty three patients undergoing CABG were included. Patients in Group A (n?=?119) all operated by one physical assistant (PA) were prospectively randomised into Group A1 (n?=?59) receiving intracutaneous closure suture alone whereas 60 patients (Group A2) received an additional subcutaneous suture line. Group B (n?=?120), operated by surgical residents, served as control population. All patients were due to follow-up at six weeks p.o. Results. Subcutaneous suture did not impact the p.o. infection rate (A2 vs. A1; 4/60 vs. 2/59, n.s.). A significant lower p.o. infection rate was observed in Group A vs. Group B (6/119 (5%) vs. 15/120 (13%) p?<?0.05). Conclusion. Subcutaneous suture did not impact the p.o. infection rate at VSMHS. The infection rate observed in patients operated by an experienced PA was significantly lower than in patients operated by various surgical residents.     

Clinical significance of isolated mega cisterna magna

Objective The prevalence and clinical significance of isolated mega cisterna magna in both fetuses and adults is not yet well defined. It is therefore difficult to provide reliable parental counseling in cases of a fetal sonographic diagnosis of this anomaly. The aim of the present study was to, determine the cognitive profile of adults with isolated mega cisterna magna. Methods We reviewed 19,301 consecutive CT/MRI of the brain. Isolated mega cisterna magna was observed in 49 cases. A battery of neuropsychological tests was performed in 18 adults with this anomaly and in 18 controls who had no brain anomaly on CT/MRI. Results Subjects with isolated mega cisterna magna had a lower performance on memory tasks [RAVLT saving score (0.8 ± 0.2 vs. 1.02 ± 0.2, P = 0.003)] and verbal fluency [phonemic fluency (9.4 ± 4.5 vs. 13.6 ± 5.3, P = 0.02), semantic fluency (19.8 ± 5.8 vs. 24.4 ± 7.5, P = 0.05)]. They did not differ from controls in regard to the Raven similarity tests indicating that this brain anomaly is not associated with impairment of general cognitive abilities. Conclusion Adults with isolated mega cisterna have an overall normal cognitive functioning but may score inferior to controls on some parameters of memory and verbal fluency. Although application of adult cases to the fetuses is not well established, this information might be of value in parental counseling in cases of a fetus with this anomaly.     

高位结扎和皮内缝扎治疗原发大隐静脉曲张

目的 探索大隐静脉曲张的外科治疗方法.方法 总结分析56例大隐静脉曲张采用高位结扎加皮内缝扎法治疗及预后.结果 术后患肢疼痛轻,无1例皮下血肿,皮内缝合处无1例感染,术后早期有6例(10.7%)皮内缝合处疼痛较重,半个月后好转,有2例(3.34%)在皮内缝合处有小硬结,经热敷、理疗后消失.所有病人均随访1～6个月,无1例深静脉血栓形成.结论 该术式是一种疗效确切,并发症少的手术方式.     

结膜吸吮线虫实验室感染大绕眼果蝇

在安徽黄山地区捕捉有绕眼习性的果蝇,将结膜吸吮线虫初产蚴混于果汁中,实验室喂饲感染果蝇,常温饲养20 d后,检查果蝇的感染情况。结果显示,大绕眼果蝇（Amiota magna）和冈田绕眼果蝇（A. okadai）的阳性率分别为30%（30/100）和21.6%（55/255）,两者间的差异无统计学意义（χ²=0.058 4, P>0.05）。将采自大绕眼果蝇的结膜吸吮线虫感染期幼虫接种家兔,35 d后在兔结膜囊内检获结膜吸吮线虫成虫及其初产蚴,表明在实验室条件下,结膜吸吮线虫可感染大绕眼果蝇。