A measure of knowledge flow between specific fields: Implications of interdisciplinarity for impact and funding.

Encouraging knowledge flow between mutually relevant disciplines is a worthy aim of research policy makers. Yet, it is less clear what types of research promote cross-disciplinary knowledge flow and whether such research generates particularly influential knowledge. Empirical questions remain as to how to identify knowledge-flow mediating research and how to provide support for this research. This study contributes to addressing these gaps by proposing a new way to identify knowledge-flow mediating research at the individual research article level, instead of at more aggregated levels. We identify journal articles that link two mutually relevant disciplines in three ways-aggregating, bridging, and diffusing. We then examine the likelihood that these papers receive subsequent citations or have funding acknowledgments. Our case study of cognitive science and educational research knowledge flow suggests that articles that aggregate knowledge from multiple disciplines are cited significantly more often than are those whose references are drawn primarily from a single discipline. Interestingly, the articles that meet the criteria for being considered knowledge-flow mediators are less likely to reflect funding, based on reported acknowledgements, than were those that did not meet these criteria. Based on these findings, we draw implications for research policymakers.

Tracking the emergence of synthetic biology.

Synthetic biology is an emerging domain that combines biological and engineering concepts and which has seen rapid growth in research, innovation, and policy interest in recent years. This paper contributes to efforts to delineate this emerging domain by presenting a newly constructed bibliometric definition of synthetic biology. Our approach is dimensioned from a core set of papers in synthetic biology, using procedures to obtain benchmark synthetic biology publication records, extract keywords from these benchmark records, and refine the keywords, supplemented with articles published in dedicated synthetic biology journals. We compare our search strategy with other recent bibliometric approaches to define synthetic biology, using a common source of publication data for the period from 2000 to 2015. The paper details the rapid growth and international spread of research in synthetic biology in recent years, demonstrates that diverse research disciplines are contributing to the multidisciplinary development of synthetic biology research, and visualizes this by profiling synthetic biology research on the map of science. We further show the roles of a relatively concentrated set of research sponsors in funding the growth and trajectories of synthetic biology. In addition to discussing these analyses, the paper notes limitations and suggests lines for further work.

Analyzing collaboration networks and developmental patterns of nano-enabled drug delivery (NEDD) for brain cancer.

The rapid development of new and emerging science & technologies (NESTs) brings unprecedented challenges, but also opportunities. In this paper, we use bibliometric and social network analyses, at country, institution, and individual levels, to explore the patterns of scientific networking for a key nano area - nano-enabled drug delivery (NEDD). NEDD has successfully been used clinically to modulate drug release and to target particular diseased tissues. The data for this research come from a global compilation of research publication information on NEDD directed at brain cancer. We derive a family of indicators that address multiple facets of research collaboration and knowledge transfer patterns. Results show that: (1) international cooperation is increasing, but networking characteristics change over time; (2) highly productive institutions also lead in influence, as measured by citation to their work, with American institutes leading; (3) research collaboration is dominated by local relationships, with interesting information available from authorship patterns that go well beyond journal impact factors. Results offer useful technical intelligence to help researchers identify potential collaborators and to help inform R&D management and science & innovation policy for such nanotechnologies.

Ischemic stroke among the patients with end-stage renal disease who were undergoing maintenance dialysis.

PURPOSE: In spite of higher incidence of stroke in end-stage renal disease (ESRD) patients compared to general population, the risk factor for stroke which is specific to ESRD is not fully understood. The ESRD patients who develop stroke may have certain additional risk factors compared to ESRD patients without stroke. We used registered data of Hallym Stroke Registry to elucidate the factors which affect development of ischemic stroke among the dialysis patients. MATERIALS AND METHODS: We recruited patients with acute ischemic stroke in ESRD patients undergoing maintenance dialysis. Dialysis patients without stroke were selected as control group with age and gender matching. We compared the demographic features, stroke risk factors, and laboratory findings in ESRD patients with or without ischemic stroke. RESULTS: The total of 25 patients with ESRD developed ischemic stroke. Fifty ESRD patients without stroke were chosen as the control group. The mean age of acute ischemic stroke patients was 59.80±9.94 and male gender was 48%. The most common ischemic stroke subtype was small vessel occlusion (n=12), followed by large artery atherosclerosis (n=7). The patients with stroke had more frequent history of hypertension and higher systolic/diastolic blood pressure at the time of admission than the ESRD patients without stroke. Total cholesterol and LDL-cholesterol levels were significantly lower in the stroke group. In multivariate analysis, LDL-cholesterol was found to be the only risk factor for ischemic stroke. CONCLUSION: The results of our study reveal that LDL-cholesterol is associated with greater risk for ischemic stroke in the patients on dialysis.

Safety and efficacy of ultrasound-guided fiducial marker implantation for CyberKnife radiation therapy.

OBJECTIVE: To evaluate the safety and technical success rate of an ultrasound-guided fiducial marker implantation in preparation for CyberKnife radiation therapy. MATERIALS AND METHODS: We retrospectively reviewed 270 percutaneous ultrasound-guided fiducial marker implantations in 77 patients, which were performed from June 2008 through March 2011. Of 270 implantations, 104 were implanted in metastatic lymph nodes, 96 were in the liver, 39 were in the pancreas, and 31 were in the prostate. During and after the implantation, major and minor procedure-related complications were documented. We defined technical success as the implantation enabling adequate treatment planning and CT simulation. RESULTS: The major and minor complication rates were 1% and 21%, respectively. One patient who had an implantation in the liver suffered severe abdominal pain, biloma, and pleural effusion, which were considered as major complication. Abdominal pain was the most common complication in 11 patients (14%). Among nine patients who had markers inserted in the prostate, one had transient hematuria for less than 24 hours, and the other experienced transient voiding difficulty. Of the 270 implantations, 261 were successful (97%). The reasons for unsuccessful implantations included migration of fiducial markers (five implantations, 2%) and failure to discriminate the fiducial markers (three implantations, 1%). Among the unsuccessful implantation cases, six patients required additional procedures (8%). CONCLUSION: The symptomatic complications following ultrasound-guided percutaneous implantation of fiducial markers are relatively low. However, careful consideration of the relatively higher rate of migration and discrimination failure is needed when performing ultrasound-guided percutaneous implantations of fiducial markers.

Normal diffusion-weighted MRI during the acute stage of central pontine myelinolysis.

Central pontine myelinolysis (CPM) is rare demyelinating disorder characterized by loss of myelin in the center of the basis pontis. The clinical features of CPM vary depending on the involved areas. Diffusion-weighted imaging (DWI) is thought to be useful for early detection during the acute phase, but its utility in this context has not been investigated thoroughly. We report the case of a CPM patient with normal initial DWI findings even at 1 week after symptom onset. To the best of our knowledge, no such cases of CPM have previously been reported.

Ipsilateral tilt and contralateral sensory change of neck in cortical infarction.

BACKGROUND: Numerous neck muscles are involved in neck movements, and so isolated neck weakness is extremely uncommon in cerebral infarction. CASE REPORT: We report herein the case of a 65-year-old woman with hypertension and acute cortical infarction, presenting with ipsilateral head tilt and contralateral sensory changes in the neck and shoulder area, which has never been described before. CONCLUSIONS: Transient neck weakness and sensory deficits can occur in acute cortical infarction. The motor representation of the neck muscles can be at the same level of the cortical sensory representation, near to the level of the trunk representation, which is in contrast to Penfield's findings. Several possible mechanisms for the ipsilateral tilt are described.

A case of vascular hemichorea responding to topiramate.

Although vascular chorea often comes into remission spontaneously, a few patients may remain with persistent movement disorder. Most movements respond well to neuroleptics as well as other antidopaminergic drugs, but some patients show poor responses to those neuroleptics. Topiramate is a widely used of broad-spectrum anticonvulsant possessing a complex mechanism of action. It has been proven to enhance gamma-aminobutyrate acid activity and to be effective in the control of other movement disorders. We describe a 63-year-old woman with intractable vascular hemichorea which was controlled with anti-convulsant, topiramate.

Prognosis of ocular myasthenia in Korea: a retrospective multicenter analysis of 202 patients.

OBJECTIVES: The aims of this study were to obtain data on the frequency with which Korean patients with autoimmune myasthenia gravis (MG) present solely with ocular disturbances and progress to develop generalized disease and to identify the prognostic factors associated with secondary generalization. METHODS: We conducted a retrospective multicenter survey in which a total of 376 adult patients who were newly diagnosed with MG from 2000 through 2005 were reviewed for analysis. Patients with ocular MG at the time of symptom presentation (n=202, 53.7%) were divided into two subgroups according to their prognosis: the patients whose disease remained ocular throughout the follow-ups were placed in the OMG-R group, and the patients who progressed to develop generalized disease were placed in the OMG-G group. Clinical characteristics and laboratory findings were compared between the two subgroups. RESULTS: Secondary generalization developed in 47 (23.3%) of the 202 study subjects, mostly within the first 6 months after symptom presentation, while the disease remained ocular throughout the follow-up duration (median 11.8 months) in the remaining 155 patients (76.7%). AChR antibody, abnormal repetitive nerve stimulation tests (RNST) and thymoma were more frequently observed in the patients in the OMG-G group than in those in the OMG-R group (p<0.01 in all). In seropositive cases, the titers of AChR antibody were also significantly higher in the OMG-G group than in the OMG-R group (median, 3.8 nM vs. 6.4 nM; p<0.05). Cox proportional hazards regression analyses showed that early oral prednisolone treatment significantly reduced the risk of secondary generalization (HR, 0.24; 95% CI, 0.11-0.56), whereas abnormal AChR antibody (HR, 5.34; 95% CI, 1.60-17.8) and thymoma (HR, 2.32; 95% CI, 1.21-4.45) were predictive of the development of secondary generalization. CONCLUSIONS: Our findings suggest that several factors, including the AChR antibody, thymoma, early corticosteroid treatment, and possibly latent neuromuscular abnormality revealed by RNST, may have an impact on the risk of developing generalized disease in Korean patients presenting with ocular myasthenia.

Complete Binocular Blindness as the First Manifestation of HIV-Related Cryptococcal Meningitis.

Ocular complications of HIV-related cryptococcal meningitis are reasonably common, but complete binocular blindness as the first manifestation of HIV is extremely rare. A 58-year-old man presented with binocular blindness. He experienced blurred vision for 3 days before the blindness. Mild pleocytosis was present in the cerebrospinal fluid, from which Cryptococcus neoformans was cultured. Serology revealed positivity for HIV antibody. He was treated with antifungal and antiretroviral therapy. This case indicates that HIV-related cryptococcal meningitis should be taken into consideration when determining the cause of unexpected sudden binocular blindness.

The clinico-radiologic properties of deep small basal ganglia infarction: lacune or small striatocapsular infarction?

OBJECTIVE: Deep small basal ganglia infarction (DSBI) cannot be clearly classified as either lacune or striatocapsular infarction by their sizes only. We tried to elucidate clinical and other properties of DSBI to understand better in pathophysiology of ischemic lesion of basal ganglia. METHODS: We analyzed 36 patients with acute ischemic lesion of basal ganglia with the size varying from 1.5 to 3 cm in maximal diameters. We assessed clinical features, laboratory data, risk factors of stroke, and radiologic findings such as MRI and MR angiography. RESULTS: Patients with DSBI could be largely divided into two distinctive groups, small infarction with cortical sign (SICS) and lacunar syndrome (LS) according to their presence of cortical manifestations. Total of 11 patients were in SICS group and they showed cortical manifestations such as eyeball deviation, visual field defect, aphasia and neglect. They also showed severer non-cortical neurologic deficit compared with LS group. Whereas LS group showed various MRA patterns, 7 patients of SICS group (63.6%) showed proximal MCA stenosis in MRA. CONCLUSIONS: We found that many patients with DSBI could have the features of either lacune or striatocapsular infarction. Although they have similar morphologic characteristics but they are presumed to have different pathophysiologic mechanism.