Incidence of needle‐tract seeding following prostate biopsy for suspected cancer: a review of the literature

With the widespread clinical use of prostate‐specific antigen (PSA), biopsy of the prostate has become one of the most commonly performed urological procedures. In general it is well tolerated, although there is some morbidity and risk of infection. In recent years, there have been increasing concerns that prostate biopsy may lead to tumour seeding along the needle tract. The aim of the present paper was to review the evidence on the prevalence of tumour seeding after prostate biopsy and to define the risk of this event in the context of current clinical practice. A PubMed literature search was conducted in January 2014 according to the Preferred Reporting Items for Systematic Reviews and Meta‐analysis (PRISMA) statement. Literature was examined with emphasis on the incidence of seeding, clinical presentation and on risk factors including type of needle used, transrectal vs transperineal approach, as well as tumour grade and stage. In all, 26 publications were identified reporting needle‐tract seeding after prostate biopsy. In all, 42 patients with needle‐tract seeding were identified. In most cases, seeding was reported after transperineal biopsy of the prostate, while nine cases occurred after transrectal biopsy. Based on the reviewed series the incidence of seeding appears to be <1%. The increase in the number of biopsies and cores taken at each biopsy over the years has not resulted in an increase in the reported cases of seeding. In conclusion, seeding along the needle track is a rare complication after prostate biopsy. Its actual incidence is presently difficult to quantify. It is reasonable to advise appropriate counselling and take measures to reduce this event where possible; however, we do not advocate avoidance of biopsies as the benefits of appropriate cancer diagnosis and management outweigh any potential risks from seeding.     

单中心直肠癌根治性前切除术后局部复发危险因素分析

回顾性分析直肠癌根治性前切除术后局部复发患者23例与按性别、年龄挑选出的未复发患者69 例,分析直肠癌根治性前切除术后局部复发危险因素. 单因素分析结果显示,肿瘤直径、术后病理阳性淋巴结个数、肿瘤位置高低及T分期是直肠癌根治性前切除术后局部复发的危险因素.Logistic回归分析显示:T分期( T4期)是影响直肠癌根治性前切除术后局部复发的独立因素,肿瘤位置高低(肿瘤距肛缘小于5 cm)则近似构成局部复发的独立危险因素.     

Rules of formation of H–C–N–O compounds at high pressure and the fates of planetary ices

The solar system’s outer planets, and many of their moons, are dominated by matter from the H–C–N–O chemical space, based on solar system abundances of hydrogen and the planetary ices H2O, CH4, and NH3. In the planetary interiors, these ices will experience extreme pressure conditions, around 5 Mbar at the Neptune mantle–core boundary, and it is expected that they undergo phase transitions, decompose, and form entirely new compounds. While temperature will dictate the formation of compounds, ground-state density functional theory allows us to probe the chemical effects resulting from pressure alone. These structural developments in turn determine the planets’ interior structures, thermal evolution, and magnetic field generation, among others. Despite its importance, the H–C–N–O system has not been surveyed systematically to explore which compounds emerge at high-pressure conditions, and what governs their stability. Here, we report on and analyze an unbiased crystal structure search among H–C–N–O compounds between 1 and 5 Mbar. We demonstrate that simple chemical rules drive stability in this composition space, which explains why the simplest possible quaternary mixture HCNO—isoelectronic to diamond—emerges as a stable compound and discuss dominant decomposition products of planetary ice mixtures.

Crystal structure prediction coupled to electronic structure calculations has emerged as a powerful tool in computational materials science, in particular in the area of high-pressure science, where it can overcome the chemical imagination attuned to ambient conditions: The predictions—and subsequent experimental confirmations—of unusual compounds such as Na2He, H3S, or LaH10 attest to the predictive power of these approaches (1–6). The planetary ices H2O, CH4, and NH3 may dominate the interiors of icy planets, but under extreme conditions (7–10). High-pressure phases of these ices have been explored computationally, and some predictions of exotic phases of individual ices have also been confirmed by experiments (11–15). Arguably, computational predictions in this field are of crucial importance because of the challenges for laboratory experiments and the indirect nature of astronomical observations. However, with increasing number of constituents the structure searches become computationally much more demanding. Hence, while structure predictions for elemental and binary systems are routine there are far fewer extensive searches of ternary systems, and none for quaternary systems.The situation in the H–C–N–O quaternary system reflects this. A vast number of publications exist on the high-pressure evolution of the individual constituents H, C, N, and O (16–19). Binary systems have also been looked at in great detail (20–24). The ternary systems are much less investigated: While H–C–O, H–N–O, and C–N–O phase diagrams have been reported (25–27), the H–C–N ternary has not, for example. The PubChem database (28) lists just under 4.8 million molecular H–C–N compounds. Overall, it contains 44.6 million H–C–N–O compounds at ambient pressure, 78% of which are of true quaternary composition—this highlights both the complexity and the relevance of this quaternary system for organic chemistry. Back in the high-pressure area, some binary mixtures of planetary ices, for instance H2O–NH3 or N2–CH4 mixtures, which form a subset of the H–N–O and H–C–N ternaries, have been studied in simulations into the megabar pressure range (29–32). However, despite the overall importance of H–C–N–O both to planetary science and Earth-bound chemical and life sciences, to our knowledge there are no computational high-pressure studies of this system, or even subsets that include all four elements, for example binary or ternary molecular mixtures such as CO2–NH3 or NH3–H2O–CH4. Here, we explore the full H–C–N–O chemical space via crystal structure searches performed at 500 GPa. This resembles the pressure—if not the temperature—at Neptune’s core–mantle boundary and therefore helps illuminate potential pressure-induced chemical reactions in the deep interiors of the outer planets and giant icy exoplanets. It also helps us understand more generally what rules govern a familiar composition space at highly unfamiliar external conditions.     

Automatic Identification of Web-Based Risk Markers for Health Events

Background

The escalating cost of global health care is driving the development of new technologies to identify early indicators of an individual’s risk of disease. Traditionally, epidemiologists have identified such risk factors using medical databases and lengthy clinical studies but these are often limited in size and cost and can fail to take full account of diseases where there are social stigmas or to identify transient acute risk factors.

Objective

Here we report that Web search engine queries coupled with information on Wikipedia access patterns can be used to infer health events associated with an individual user and automatically generate Web-based risk markers for some of the common medical conditions worldwide, from cardiovascular disease to sexually transmitted infections and mental health conditions, as well as pregnancy.

Methods

Using anonymized datasets, we present methods to first distinguish individuals likely to have experienced specific health events, and classify them into distinct categories. We then use the self-controlled case series method to find the incidence of health events in risk periods directly following a user’s search for a query category, and compare to the incidence during other periods for the same individuals.

Results

Searches for pet stores were risk markers for allergy. We also identified some possible new risk markers; for example: searching for fast food and theme restaurants was associated with a transient increase in risk of myocardial infarction, suggesting this exposure goes beyond a long-term risk factor but may also act as an acute trigger of myocardial infarction. Dating and adult content websites were risk markers for sexually transmitted infections, such as human immunodeficiency virus (HIV).

Conclusions

Web-based methods provide a powerful, low-cost approach to automatically identify risk factors, and support more timely and personalized public health efforts to bring human and economic benefits.     

Comparing image search behaviour in the ARRS GoldMiner search engine and a clinical PACS/RIS

Information search has changed the way we manage knowledge and the ubiquity of information access has made search a frequent activity, whether via Internet search engines or increasingly via mobile devices. Medical information search is in this respect no different and much research has been devoted to analyzing the way in which physicians aim to access information. Medical image search is a much smaller domain but has gained much attention as it has different characteristics than search for text documents. While web search log files have been analysed many times to better understand user behaviour, the log files of hospital internal systems for search in a PACS/RIS (Picture Archival and Communication System, Radiology Information System) have rarely been analysed. Such a comparison between a hospital PACS/RIS search and a web system for searching images of the biomedical literature is the goal of this paper. Objectives are to identify similarities and differences in search behaviour of the two systems, which could then be used to optimize existing systems and build new search engines.Log files of the ARRS GoldMiner medical image search engine (freely accessible on the Internet) containing 222,005 queries, and log files of Stanford’s internal PACS/RIS search called radTF containing 18,068 queries were analysed. Each query was preprocessed and all query terms were mapped to the RadLex (Radiology Lexicon) terminology, a comprehensive lexicon of radiology terms created and maintained by the Radiological Society of North America, so the semantic content in the queries and the links between terms could be analysed, and synonyms for the same concept could be detected. RadLex was mainly created for the use in radiology reports, to aid structured reporting and the preparation of educational material (Lanlotz, 2006) [1]. In standard medical vocabularies such as MeSH (Medical Subject Headings) and UMLS (Unified Medical Language System) specific terms of radiology are often underrepresented, therefore RadLex was considered to be the best option for this task.The results show a surprising similarity between the usage behaviour in the two systems, but several subtle differences can also be noted. The average number of terms per query is 2.21 for GoldMiner and 2.07 for radTF, the used axes of RadLex (anatomy, pathology, findings, …) have almost the same distribution with clinical findings being the most frequent and the anatomical entity the second; also, combinations of RadLex axes are extremely similar between the two systems. Differences include a longer length of the sessions in radTF than in GoldMiner (3.4 and 1.9 queries per session on average). Several frequent search terms overlap but some strong differences exist in the details. In radTF the term “normal” is frequent, whereas in GoldMiner it is not. This makes intuitive sense, as in the literature normal cases are rarely described whereas in clinical work the comparison with normal cases is often a first step.The general similarity in many points is likely due to the fact that users of the two systems are influenced by their daily behaviour in using standard web search engines and follow this behaviour in their professional search. This means that many results and insights gained from standard web search can likely be transferred to more specialized search systems. Still, specialized log files can be used to find out more on reformulations and detailed strategies of users to find the right content.     

A research framework for pharmacovigilance in health social media: Identification and evaluation of patient adverse drug event reports

Social media offer insights of patients’ medical problems such as drug side effects and treatment failures. Patient reports of adverse drug events from social media have great potential to improve current practice of pharmacovigilance. However, extracting patient adverse drug event reports from social media continues to be an important challenge for health informatics research. In this study, we develop a research framework with advanced natural language processing techniques for integrated and high-performance patient reported adverse drug event extraction. The framework consists of medical entity extraction for recognizing patient discussions of drug and events, adverse drug event extraction with shortest dependency path kernel based statistical learning method and semantic filtering with information from medical knowledge bases, and report source classification to tease out noise. To evaluate the proposed framework, a series of experiments were conducted on a test bed encompassing about postings from major diabetes and heart disease forums in the United States. The results reveal that each component of the framework significantly contributes to its overall effectiveness. Our framework significantly outperforms prior work.     

超声引导下Mammotome治疗乳腺局灶性病变的常见并发症分析及防治措施

目的探讨超声引导下Mammotome微创旋切系统治疗乳腺局灶性病变的常见并发症及防治措施。方法收集超声引导下Mammotome治疗的乳腺局灶性病变2125例,术后随访3个月,对术中及术后产生的并发症进行总结分析,探讨其防治措施。结果 2125例患者共出现并发症376例,发生率17.69%。血肿328例,其中术中活动性出血并血肿316例,术后24 h内血肿8例,术后1~3 d血肿4例。皮下瘀斑43例,其中单纯皮下瘀斑15例均自行吸收消退,28例皮下瘀斑合并不同程度的血肿。胸大肌损伤15例;皮肤损伤6例;心包胸腔积液和术后疤痕结节各1例。6级以上疼痛者32例,其中22例合并其他并发症,12例单纯性剧烈疼痛。结论超声引导下Mammotome治疗乳腺局灶性病变因其快速、美观而迅速发展,但并发症发生率较高,通过积极的术前准备、术中医师的协调配合、改善手术技巧及术后护理可减少或避免并发症发生,提高Mammotome手术治疗乳腺病变的效果,具有较高的临床价值。     

Lidocaine‐Propitocain Cream,a Eutectic Mixture of Local Anesthetics,Effectively Relieves Pain Associated With Vascular Access Intervention Therapy in Patients Undergoing Hemodialysis: A Placebo‐Controlled,Double‐Blind,Crossover Study

Vascular access intervention therapy (VAIVT) is necessary to maintain vascular access in patients undergoing hemodialysis. VAIVT‐associated vasodilatation is painful. However, few reports have focused on effective pain relief at the time of VAIVT. The present study was performed to determine whether lidocaine‐propitocain cream, a eutectic mixture of local anesthetics (EMLA), effectively reduces VAIVT‐associated pain in patients undergoing hemodialysis. This placebo‐controlled, double‐blind, crossover study was conducted in a single center. Among 210 patients who underwent a total of 437 VAIVT procedures from August 2017 to June 2018, 30 patients were randomly allocated to either the EMLA–placebo arm or placebo–EMLA arm at the time of VAIVT. EMLA application significantly reduced the visual analog scale score compared with placebo (47.0 ± 21.1 vs. 68.6 ± 20.7 mm, respectively; P < 0.05). EMLA is a safe and effective treatment for relief of VAIVT‐associated pain in patients undergoing hemodialysis.     

Intensity-based image registration using scatter search

ObjectiveWe present a novel intensity-based algorithm for medical image registration (IR).Methods and materialsThe IR problem is formulated as a continuous optimization task, and our work focuses on the development of the optimization component. Our method is designed over an advanced scatter search template, and it uses a combination of restart and dynamic boundary mechanisms integrated within a multi-resolution strategy.ResultsThe experimental validation is performed over two datasets of human brain magnetic resonance imaging. The algorithm is evaluated in both a stand-alone registration application and an atlas-based segmentation process targeted to the deep brain structures, considering a total of 16 and 18 scenarios, respectively. Five established IR techniques, both feature- and intensity-based, are considered for comparison purposes, and ground-truth data is used to quantitatively assess the quality of the results. Our approach ranked first in both studies and it is able to outperform all competitors in 12 of 16 registration scenarios and in 14 of 18 registration-based segmentation tasks. A statistical analysis confirms with high confidence (p < 0.014) the accuracy and applicability of our method.ConclusionsWith a proper, problem-specific design, scatter search is able to provide a robust, global optimization. The accuracy and reliability of the registration process are superior to those of classic gradient-based techniques.