Blood Pressure Recordings During Hemodialysis Access Interventions: Implications for Acute Management

A retrospective study evaluating the pattern of blood pressure and its related complications before, during, and after percutaneous hemodialysis interventions was performed in patients presenting with asymptomatic hypertension. Hemodialysis patients undergoing percutaneous interventions including tunneled hemodialysis catheter insertion, percutaneous balloon angioplasty and thrombectomy procedure, and stage II hypertension (systolic blood pressure ≥160 mmHg) were included in this analysis. Blood pressure medications were not used while midazolam and fentanyl were routinely administered. Patients were followed for up to 4 weeks to monitor any complications. The mean blood pressure before, during, and after the procedures were 185 ± 18/96 ± 14, 172 ± 22/92 ± 15, and 153 ± 25/87 ± 14, respectively. There was a statistically significant difference between the blood pressure readings before and after the procedure (before = 185 ± 18/96 ± 14, after = 153 ± 25/87 ± 14; p = 0.001). None of the patients had a stroke, myocardial infarction, or acute pulmonary edema before, during, or after the procedure or during the 4‐week follow‐up period. A significant reduction in blood pressure was observed after the procedure without the administration of any antihypertensive medication. These results suggest that the reduction in blood pressure observed after percutaneous dialysis access interventions (particularly in the presence of midazolam and fentanyl) may make it unnecessary to treat asymptomatic hypertension prior to these procedures.     

Orientation-specific relationship between populations of excitatory and inhibitory lateral connections in the visual cortex of the cat

The topography of lateral excitatory and lateral inhibitory connections was studied in relation to orientation maps obtained in areas 17 and 18. Small iontophoretic injections of biocytin were delivered to the superficial layers in regions where orientation selectivity had been mapped using electrode recordings of single- and multi-unit activity from various cortical depths. Biocytin revealed extensive patchy axonal projections of up to 3.5 mm in both areas while labelled somata occurred chiefly at the injection site, indicating that the labelling was primarily anterograde. Two types of boutons could be clearly distinguished: (i) putative excitatory boutons either en passant or having a short stalk and (ii) inhibitory boutons which were invariably of the basket-type. Three-dimensional reconstructions of all labelled boutons showed that the excitatory and the inhibitory networks had a distinctively different relationship to orientation maps. The overall distribution of connections showed that 53-59% of excitatory and 46-48% of inhibitory connections were at iso-orientation, +/-30 degrees; oblique-orientation, +/-(30-60) degrees, was shown by 30% of excitatory and 28-39% of inhibitory connections; cross-orientation was shown by 11- 17% of excitatory and 15-24% of inhibitory connections. Although excitatory patches occupied mainly iso-orientation locations, interpatch regions representing chiefly non-iso-orientations (oblique + cross orientation) were also innervated. There was considerable overlap between the excitatory and inhibitory network. Nonetheless, inhibitory connections were more common than excitatory connections with non-iso- orientation locations. There was no significant difference between the orientation topography of area 17 and area 18 projections. The results suggest that in general the lateral connectivity system is not orientation specific, but shows a moderate iso-orientation preference for excitation and an even weaker iso-orientation preference for inhibition. The broad orientation spectrum of lateral connections could provide the basis for mechanisms that requiring different orientations, as for example in detecting orientation discontinuities.      

口服抗凝药物实验室监测方法研究

对口服抗凝药物实验监测有关方法进行了探讨，介绍了一种简便易行较为敏感的实验方法“Hepato－Quick”。实验表明：此法所用试剂加入因子V和纤维蛋白原，大大提高了试验的特异性。所采用的稀释法，减少了非特异性抗凝物质对试验的干扰。该法突出的优点是可采用毛细血管血进行检测。比较表明：血浆法与毛细血管法有良的相关性（r＝0.9836，P＜0.001）。     

次氯酸钠对隐孢子虫卵囊在体外脱囊的影响

隐孢子虫卵囊的无菌化及体外脱囊是进行虫体体外细胞培养不可缺少的环节，本试验通过使用不同浓度次氯酸钠提前处理卵囊，在不同脱囊液的条件下比较各处理组的脱囊率。试验结果表明，未经任何处理的卵囊，在37C的温度下可发生脱囊，但脱囊率只有15．5％（脱囊时间90min）；经100％bleach（含5．25％次氨酸钠）作用30min，对卵囊的活性有很大的影响，在T＋TDC（Trypsin＋taurodeoxycholicacid）脱囊液中，其脱囊率只有17％（约正常卵囊的20％）；5％～20％的bleach对卵囊的活性没有明显的影响，反而有很强的刺激脱囊作用，卵囊经这一浓度范围的bleach处理后．即使没有酶的存在，其脱囊率也可达到80％以上。单独使用酶或bleach均有很好的脱囊作用，但两者合并使用，并不能提高新鲜卵囊的脱囊率。对用于细胞培养的卵囊，推荐用10％～20％bleach处理30min，这一处理，既可得到无菌化的卵囊，又有高的脱囊率。     

Renal Artery Stenosis: To Intervene,or Not to Intervene, “That is the Question”

Renal artery stenosis (RAS) due to atherosclerosis continues to be a major cause of secondary hypertension. It can also lead to renal dysfunction due to ischemic nephropathy. While major clinical trials have emphasized that medical management should be preferred over angioplasty and stenting for the treatment of renal artery stenosis, clinical scenarios continue to raise doubts about the optimal management strategy. Herein, we present two cases that were admitted with hypertensive emergency and renal function deterioration. Medical therapy failed to control the blood pressure and in one patient, renal failure progressed to a point where renal replacement therapy was required. Both patients underwent angioplasty (for >90% stenosis) and stent insertion with successful resolution of stenosis by interventional radiology. Postoperatively, blood pressure gradually decreased with improvement in serum creatinine. Dialysis therapy was discontinued. At 4‐ and 8‐month follow‐up, both patients continue to do well with blood pressure readings in the 132–145/70–90 mmHg range. This article highlights the importance of percutaneous interventions in the management of atherosclerotic RAS and calls for heightened awareness and careful identification of candidates who would benefit from angioplasty and stent insertion.     

Human abdominal aorta: comparative measurements of blood flow with MR imaging and multigated Doppler US

Magnetic resonance (MR) imaging has proved to be a new alternative method for the noninvasive detection and quantification of blood flow in human vessels. By means of standard gradient echo sequences triggered with electrocardiography on a 1.5-T whole-body imaging system, the authors measured the flow-induced phase shift in the abdominal aorta of healthy volunteers. The instantaneous two-dimensional velocity profiles and the integrated flow rate were determined in intervals down to 21 msec throughout the cardiac cycle. The results were validated by means of comparative measurements with a multigated Doppler ultrasound instrument. The velocity values acquired with this instrument in one spatial dimension in the anteroposterior direction of the abdominal aorta agreed to a great extent with the temporal and spatial corresponding values recorded with MR imaging. The same high correlation between the two methods was found for the calculated instantaneous total blood flow.     

Cancer cell invasion and EMT marker expression: a three‐dimensional study of the human cancer–host interface

Cancer cell invasion takes place at the cancer–host interface and is a prerequisite for distant metastasis. The relationships between current biological and clinical concepts such as cell migration modes, tumour budding and epithelial–mesenchymal transition (EMT) remains unclear in several aspects, especially for the 'real' situation in human cancer. We developed a novel method that provides exact three‐dimensional (3D) information on both microscopic morphology and gene expression, over a virtually unlimited spatial range, by reconstruction from serial immunostained tissue slices. Quantitative 3D assessment of tumour budding at the cancer–host interface in human pancreatic, colorectal, lung and breast adenocarcinoma suggests collective cell migration as the mechanism of cancer cell invasion, while single cancer cell migration seems to be virtually absent. Budding tumour cells display a shift towards spindle‐like as well as a rounded morphology. This is associated with decreased E‐cadherin staining intensity and a shift from membranous to cytoplasmic staining, as well as increased nuclear ZEB1 expression. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.